Hello Juan. From a Kiwi aviation and sailing fan here who loves your channel. Wonderful to see that some US viewers are getting exposed to this exciting racing happening on our doorstep. As a yachty and America's Cup fan, I wanted to share some tweaks or corrections to your explanation of how these boats work. The main foil arms can be cranked (canted) vertically up and down about a fore-aft axis. Looking at the boat from the stern, and considering a normal keel straight down position to be zero degrees, the foil arm sits out at about 70 degree cant angle when in the water (on leeward side of the boat) and about 120 degrees when lifted out of the water (on windward side of the boat). This canting is the only direction of movement permitted on the foil arm, so some of the movements you thought you were seeing were just camera angle or perception, but didn't actually happen. The arms can't be steered like a rudder, or raked, like in the previous America's Cup catamarans where they used foil rake for flight control. The foil cant angle is used by the flight controllers to control the boats ride height. As you noted, they try and ride them as low to the water as possible to seal off the aerodynamic pressure between sail/hull and water. They also use the cant angle to adjust the heel of the boat, or in aero terms, the bank of the boat. Unlike regular monohulls that heel to leward (banking away from the wind), the AC75s can be canted to heel/bank in to the wind. Flight control in these boats is achieved in two parts. The first part of flight control is through trailing edge foil wing flaps, that can be used to increase or decrease lift on the wings. Note that without foil rake permitted, choosing the overall angle of attack for the immovable part of the wings is important, as if your wing doesn't naturally generate enough lift to fly the boat, then more wing flap angle is needed to generate sufficient lift, however this also creates extra drag. (This is believed to have been a cause of Ineos UK teams flight issues pre Christmas). At low speeds (sub 20 knots) the flap will be used to increase lift, then would progressively reduce to neutral. The boats spend a lot of time at 35-40 knots so the wing lift profile is likely to be optimized for these speeds. However the boats semi frequently operate at 40-45 knots and are believed to be capable of up to 50 knots. At these speeds the wing flaps could be used to negate excessive lift off the main wing structure, however most teams seem to be controlling excessive wing lift with the second part of flight control. The second part of flight control is with rudder rake. The rudder wings have no flaps, however the whole structure can be moved with rake. Raking the rudder backwards would angle the rudder wing downward, pitching the bow of the boat upwards, and therefore as a consequence also changing the main wing angle of attack to a slightly more pitched up position. Raking the rudder forwards angles the rudder wing upwards, creating lift at the stern, and therefore pitching the bow of the boat down, and again as a consequence changing the angle of attack of the main foil wings slightly downwards. At high speeds (over 40 knots) which we were witnessing here (I believe Patriot had rounded the mark at about 44 knots), the rudder rake is being used to generate lift, and pitch the boat downward to try and keep the whole boat lower in the water and reduce the lift generated from the main wings. However a side effect of rudder lift is the reduced rudder remaining in the water, and therefore reduced steering control. High speed mark rounding are an inherently dangerous manouvre in these boats as you have less rudder steerage and control at exactly the time you are pushing the boats to the limits of it's ability to turn/yaw. In the case of this accident Patriot was rounding the top windward mark approaching on port tack sailing into the wind, and attempting to tack to starboard, then bear away and ultimately do the ocean equivalent of a hairpin u-turn and head straight back the way they had come from. Just before the mark they tacked through the wind (crossing the boat at the bow) to change to starboard tack. This requires foil canting, initially to lower the previously airborne port foil, at which point the boat sails briefly on two foils, then when under control, raise the starboard foil to reduce drag. The foil canting is done with electrically powered hydraulic actuators that take 15 seconds to recharge after a full foil cant. So having done this tack move, Patriot was committed to the foil cant positions for at least the next 15 seconds, but it was game over before then. Having completed the tack to starboard, the Patriot was then rounding the top windward mark and bearing away (not luffing as you mentioned). During the bear away, the boat changed its angle to the wind from a point (facing the wind) to a reach (sailing across the wind). The reach position naturally powers up these AC75 boats, and when trying to accelerate at the start or in light airs, the helmsman sails at a pure reach of 90 degrees to the wind direction to try to get maximum power. At the same time, there was an increase in the windspeed measured as increasing from 18 knots to 23 knots. The recipe ingredients for an accident were all there. The boat hydraulics on timeout, while the boat is in the maximum acceleration angle to the wind, just as a gust hit. The boat speed was increasing and the helmsman was attempting to pitch the boat down, by rudder raking, with the afore mentioned side effect of reduced rudder in the water and steerage. The rigging including the running backstays others have mentioned had been set up for upwind sailing on port tack, then briefly starboard tack, and had not been eased. The boat was fully powered up, and although they'd tried to ease the jib and the main, because of the reaching wind angle, and the running backstay preventing the main from easing, the sails were overpowered. With the speed increase, all the foils and wings were generating lift, and up she went. Things that could have prevented the accident. 1 Round the other top mark, so no tack was required, but just a simple bear away. (Not chosen as they were under pressure to stay ahead of Luna Rossa, and they chose the favoured mark). 2 Depower the sails before the mark rounding and remain on dual foils until the new boat/windand therefore required foil/wing/rudder/rake positions were known. Not chosen for same reason as 1. 3 Bear away more quickly to 180 degree to the wind. Sailing true downwind massively depowers these boats. World Champion sailor Phil Robertson believes this is the approach they should have taken, but because of the complexity of the manouvre they couldn't make it stick. Anyway like all Kiwis, including defenders TeamNZ, I wish American Magic all the best and hope that they can get Patriot fixed in time to play a part in the Prada Cup semi finals in just under a fortnight.
I don’t know anything about yachts and only a little about aircraft but whatever the cause, even if someone did not pull the right lever, Juan, you seemed to describe the aerodynamics of what was happening and why in real time. Good job.Your followers enjoy your no nonsense commentary.
Enjoyed the sailing analysis! As the past VP of a sailboat company, I was always amazed at the percentage of pilots that bought our boats. Sailing is flying but you can have a beer in your hand while sailing.
Yes it is similar. I am not a pilot ,but have sailed for 50 yrs. Often while watching your plane videos things you say or explain make a lot of sense to me because of things I have learned sailing. I sail 1 person Tail draggers 12 to 16 foot type boats. Easy to buy and learn and first time out in a strong wind you will go for a swim. You need to learn to feel the wind and start your corrections almost before others realize a change is happening. AS always thanks for a great video.
Hi Juan. Fun to watch. One factor missed by your report but covered by commentary at the time was the leeward backstay was not released which didn’t allow the mainsail to be depowered which may have prevented the capsize. Also sailing still uses “port” and “starboard”. Great channel!
@@jamesknuckey1332 Nope. Those 12 meters were beautiful, stable but slow and heavy displacement boats. There has been a foiling revolution over the past ten years, with small dinghies, catamarans and even kite boards and windsurfers going to foils. Single-handed ocean sailors are now ever more using foils. The New Zealanders established foiling monohulls as the America's Cup class, partly to foster development which can extend to standard cruising and racing boats. The America's Cup has become a much more exciting and accessible spectacle for the public, especially on TV and the Internet, so much more money has flowed into it. I wonder how this will affect the 2.4mR class, which are scaled-down little 12-metre-like boats one sits in to race, therefore very suitable for paraplegic sailors, but very sedate... people are coming up with more exciting foiling alternatives www.2punkt4.de/en/2017/04/01/foil-end-2-4mr/ :-)
@@roderickcampbell2105 Is the development that goes along with the current boat designs really "amazing"? It has come down to a material battle and everything happens so fast that luck is also a big factor (the wrong wind gust in the wrong millisecond, like seen in this example). Compare that to the Vendée Globe: there is also a huge technical aspect, but the human element (endurance, mental power, smart decision-making... things you can't buy with money) is much more prominent. These are the real heros and in my opinion such a regatta is much more exciting, especially the one this year!
Juan, as a racing sailor, I was very impressed with your explanations. I know less than you about these flying boats but everything you said makes great sense to me.
Now you're in my wheelhouse Juan!. The maneuver they were attempting to execute was a "tacking bear away". Essentially, going from an upwind point of sail, immediately to downwind. Ideally, you would tack, let the boat stabilize, and head down wind gradually. This was a risky maneuver in gusty conditions, and they knew it going in. An aircraft analogy might be an unstabilized approach. They had 11 days to repair the boat, not 4. The hole is the easy part of the repair. The hard part, as others have pointed out, is the electronics. Fortunately, they have spares. The trick is getting them installed and dialed in, in time. The hydraulics apparently are fine. Though they claim that nothing exited the boat, I'm skeptical. I think there may be one very large battery sitting on the bottom of the Gulf. It's hard to explain that hole punched through carbon fiber, and a complete piece of carbon fiber being found floating in the water otherwise! IMHO. Oh... and these boats don't have a "keel". They rely entirely on the hydrofoils for stability, even when sitting still ( both deployed). ruclips.net/video/ah5V8RHE1_Y/видео.html
@@blancolirio Yes, first they tacked. Barker (the skipper) wanted to go around the left marker, because there was more wind on that side of the course. To do that, they had to tack through the wind (the wind shifts from one side of the bow to the other, as do the sails) round the upwind mark, and head down wind (bear away). Basically a180° turn. Not a big deal in medium conditions and stable wind, but risky if it's gusty. Everything has to go quickly and smoothly. The alternative was to go around the right mark and simply bear away.. That way, the wind stays on the same side of the boat as you turn down wind. It's less complicated, and less can go wrong. Of course, it would have temporarily put them on the right side of the course, with less wind. This video from the cockpit shows them approaching the mark. You can hear a crewmember suggesting that bearing off would be safer, and Barker insisting they proceed with the tack! You can see the tack as the sails shift from one side to the other, Then....BLAMO!!! ruclips.net/video/ah5V8RHE1_Y/видео.html
@@carlwilliams6977 Good analysis Carl. The tack went well.... it was the "bear-away" that got totally out of hand. :) You know what would have fixed that? A keel, lol
Looks like Captain Pete has found a new hobby! As a sailor who turned pilot, I can tell you the similarities between the 2 are incredible. Aerodynamics, weather, navigation, stability. Turbulence is just invisible swell/waves. And both require 100% concentration meaning you can (have to) leave all your day-to-day problems back on ground/shore until you are done playing about! Great mental releases
As an American, I'm rooting for the Brits this year. Just because I saw they hadn't won it before. This was definitely a surprise video from the Blancolirio channel. I like surprises.
As a professional sailboat captain that watches your channel i was first impressed by your coverage of any sailing incident, was further impressed by the analytics, then further impressed by gaining some insights! My only comment is in sailing we have velocity headers when entering wind shadow areas and thus creating stalling on aero surfaces, then can quickly return when exiting the shadow area, hence some backwinding of sails when this happens, nevertheless stalling is still appropriate😁😎
Great analysis Juan, from a different perspective from the yachties. A few things I've gleaned (not a sailor myself): The hole in the hull was 'guillotined' by the internal support structure when it crashed down They have 11 days until the semi final, I don't think they're even trying to race this weekend. They have a complete set of electronic spares. All the other teams are offering resources to get them back in the competition. The British boat has support from the Mercedes F1 team (aerodynamics), so top quality aero, computational analysis, carbon fibre construction etc. The US boat has Airbus as a sponsor. All those lines you saw with the sail removed are AFAIK not outside the sail, so, no drag (some are). There's apparently a very complex system to shape the wing/mast to achieve the desired power for each manoeuvre. As you said, they fly low to reduce bleed between high and low pressure The boats are designed to fly with the mast vertical, it's not clear to me which way it should turn to reduce pressure on the sails when it got caught in a gust and started to heel. I thought go left, or loose off the sail to catch less wind but... (not a sailor myself).
First of all a salute to Cap'n PiP. Thanks JB. Interesting design and great information and comparison to an aircraft's operation. Take care and fly safe. 🤟🏽🖖🏽
Well that was fun to watch and hear your take on it. Glad you took a chance and hit “upload” with this one. I think what made this episode work; focused on the evidence, a bit of interpretation (but importantly, no speculation since it’s peripheral to main expertise of blancolirio), and put in a good bit of news about the incident which I hadn’t received. Rock on brother!
Great review of the incident, shows that they all are balanced on a knife (aerofoil) edge all the time when 'foiling'. But, in general the most remarkable thing about these boats is that they can get a speed of over 30kts in 10kts wind, 40kts + in 15kts wind, just amazing ..!
Juan, I’ll say it again you give a better analysis from 100’s of miles away then the media can due at the scene. Appreciate the quality of your videos.
Great overview Juan. Being both a pilot and a racing catamaran sailor, you are on point with the comparison of fluid and aerodynamics. As some have mentioned, many miss the days of seat of the pants, tactical sailing in the 12m boats of old. Your tactician was held in revererance. With that said, the integration of electronics, while needed with the speed forces generated, will come with lessons such as these. This could have had a very unpleasant ending as the boat became airborne. Ask me how I know. Pray that none of these sailors/test pilots get seriously injured as they test the limits of wind and water. Keep up the great channel- you've convinced me to become a patreon!
Blancolirio To bring you closer to the aero/ hydrodynamic challenge of these boats: - Sailing upwind they are tacking against the wind with a quite low AOA in the sail, high aero speed due to wind and boat speed are adding to speed through the air (roughly 4 to 5 times the wind speed) - Sailing downwind they are gybing with the wind again low AOA, just the windspeed is subtracted from the boat speed. You have roughly double to triple of the windspeed around the sails, still a lot of lift to drive the boat but much less resistance. The boats are even faster. - the very most critical maneuver is changing between upwind and downwind, it is called bearing away. You have this high 4 times windspeed in the sails and due to the boat turning the AOA is increasing. This generates enormous momentum accelerating the boat and pressing the mast leeward. Those guys did this maneuver in the worst possible moment: During bearing away the wind gusted from 15 knots to 24 knots which caused a loss of control (rudder stalling, boat healing over, ...) From this point on they are passengers, just the boat has a speed of more than 45 Knots with a very lot of energy able to break the structures. The hull's take off is not generated by aerodynamics from the hull itself, it is generated from the leeward foil: The healing of the boat lifts the middle of the boat upward, the rudder with the foil has to stay in the water. The consequence is a radical increasing AOA the leeward wing interacting in the water. This causes the boat to jump. Once completely in the air: game over..., it is a boat. without anything in the water, there is no stability left over.
Quite fascinating (and intense) regarding all the mechanical forces at play... definitely looked as though the bow of the boat pitched up/porpoised upward (?) much more aggressively than one would ever expect to see. Would such a severe upwards pitch have more to do with those responsible for controlling the position of the sails, more to do with those responsible for controlling the hydrofoils, or the improper control/balance of both systems(?)
@@__WJK__ Those responsible for sail control are responsible for not healing over either side and forward power, very complex with quite a number of controls involved. Those responsible for "flight control" have to keep the flight height in a narrow band and minimize track in the water with quite a number of control parameters as well. They are heavily influenced by speed and healing. Not to forget the helm supported by tacticians being responsible for the right AOA in the sails and so the speed as well, finding the shortest and fastest way around the course and the tactic to beat the other boat. all aspects have interdependencies ..., a very complex scenario to run a yacht having only two connection points in the water.
Hi guys from nz I am stoked the world is Reeee even interested after all that's been going on......This channel is one of my favorites because he knows what he's talking about and he's a good guy 😉 regards NZ
Thanks for this. I couldn't work it out I though they were tacking upwind, but yes bearing away as you explained I can see more clearly what happened 👍
Another possibility - the leeward backstay wasn’t released after rounding the mark (human error). This made it impossible for the crew to release the mainsail and de-power when the gust of wind hit.
Sure seems like there’s a fine line that gets these boats into trouble and no major de power method that can save you in all cases. I feel that without a keel of some sort there just isn’t any natural tendency to round up. Can you even feel any weather helm on these things?
@@ben3989 I don't know about foiling boats, but I do windfoiling (foil windsurfing) and on a windsurfer in normal mode the forces are mostly lateral so you feel something akin to weather helm when going upwind (spent over 40 years steering racing sailboats) but when foiling, the forces are mostly vertical so I don't think they feel much weather helm on these boats. Just my opinion.
Good stuff, Juan! They actually were desperately trying to stall the main sail. That huge microburst happened just after rounding the mark and they were unable to release the leeward backstay in time to de-power the main. These boats can't use a traditional centerline backstay because of the shape of the mainsail. So they are equipped with two backstays and they normally release the leeward one at the same time they tension the windward one. If you pay attention to the boat speed you'll see that they actually generate a significant portion of their own apparent wind. I think they were around 47 mph at the start of that event and you can add that to gust front. We're talking about a Category 1 wind speed over the deck. :-) It is my understanding that the rudder is also fitted with control surfaces like elevators on an aircraft. The pilot uses them to adjust the angle of attack for those foils midship.
The thing about leeward backstay staying tensioned is correct. It prevented depowering the main sail and this resulted in heel / roll to left. As the main lifting foil is not on the centerline as the rudder lifting foil any rolling motion induces pitch motion. Since the heel/roll went out of control so did the pitch and with tjat the angle of attack of main hydrofoil which launched the boat out of the water in the hunt for the red october style.
Juan, excellent job reporting the news about "PATRIOT" the American entry AC75 (75 foot foiling mono-hull) for the 36th edition of the America's Cup from Auckland, New Zealand. The challenger series of racing titled the PRADA CUP currently taking place DOWN UNDER includes Great Britain and Italy in addition to the American challenger sponsored by the New York Yacht Club. The crew of Patriot took an unexpected salt water bath on this mark rounding. Upon further review of the video you will notice the port side running backstay was not released as it should have. There is clear evidence that the main sail is pinned against the running rigging. Normally , if the mainsheet is released that would allow the mainsail to feather (releasing the pressure) in the gusty wind conditions allowing for some control of the vessel. During this maneuver the Mainsail was not able to feather as needed. Keeping in mind that this high performance water craft was reaching a speed close to 50 MPH balancing on 2 unstable points on a liquid base. (The ocean) Things happen very very quickly for the crew and helmsman. The canting wing/foils weigh in at just under 1.4 tons each. One on the Port side and one on the Starboard side. They are designed to provide the "righting moment" or "counter balance" against wind pressure and of course the lifting of the yacht out of the water on the submerged foil once enough velocity is reached. This is how you turn a displacement racing yacht into a flyer. With only 8 -12 knots of wind the boat can reach speeds over 40 knots. Yes, a sail on a boat is an aircraft wing turned vertically. Same rules of physics apply. The difference is when you crash (KABLAMMO) you get wet instead of something worse. This design of the AC75 is cutting edge. Everyone involved is learning minute to minute and day to day. Thank you for reading. MC
Also a sailor here. I have a Catalina 34. My Grandfather who turns 102 this week flew Catalina’s in WW2. We talk fly and sailing together . Same thing ...
Great job! .. started sailing when I was 5 and just like you said it is all the same principles of aerodynamics. Here’s another similarity of sailing to flying ... it is really pretty easy UNTIL you get close to land. 👍🏼 Side side side note rumor mill is saying that it was the mechanism that operates the hydrofoil that punched that hole during the impact of that 17,000 pound hull back into the water. I believe the technical term eummf is translated to inertia for us laymen. I might be wrong.
Drag in the water is a huge factor in sailing (vs. flying). Once you're doing foiling like this sailing is no longer about just using the wind but a thin tightrope balance between the huge aerodynamic control with the sail and the very delicate hydrodynamic control with the foils and rudder. When the stern of this boat hit the water after getting lifted it basically hit the brakes, tripped over the stern and slammed back down. Another thing that happens in these cases a lot is that the the bow hits the water first and the boat pitchpoles, many of those examples on video if you want to look.
Hi Juan, yes, it's 'basically aerodynamics', but the word you're looking for is hydrodynamics. Seawater is 800 time more dense than air. Adjust control surfaces and strength members for that and the rest is pure physics and racing fun. I was glad to see you put together a video about this event. Very apt crossover for your channel. Stay safe out there. Cheers, D.
Good afternoon... These new boats are quite impressive, but color me old fashioned, i sure miss those 12 meter yachts with secret keel designs.I’m one of the many Pilot Sailers....James
these things are awesome pieces of technology, but I agree,, it's all about boat speed and, to me, although much slower, the 12m or IACC class boats allowed for much closer, much more tactical racing. I miss the battles at the start that there used to be in the old AC matches. another pilot (well, student pilot) sailor here.
I was around Ultimate 30 racing in the late 80's, Turtle Up was part of the attraction. Like Indy, it promotes R&D in Marine Engineering, a good thing.
@@johngilbert1325 It's still sailing. Technology has almost taken over, but you still have to read the wind shifts and handle the gusts. As for foiling, I wish it had come in earlier in the A-Class catamaran. Sailing an A-Class upwind, out on the wire, is Zen for sailors. Unfortunately, I had to give up sailing A-Class before foiling. I can imagine how much doing it on foils would add to the experience, but I won't experience it. ruclips.net/video/v80uH1I3oMU/видео.html The guy with white cap is Glenn Ashby, who controls Emirates Team NZ with his magic box.
Luffing and Stalling: In aerodynamic terms, a sail luffing is sort of the opposite of a sail stalling. A wing or sail stalls when the angle of attack is too great. Luffing -- the sail flapping loosely in the wind -- occurs when the angle of attack is too small.
to add some more detail as to why they heeled so far over: these boats have what are called running backstays, where there are two wires running from the top of the mast to the back of the boat. Each wire goes to one of the back corners. Those 'running' backstays have to be loosened on the downwind side to allow the sail to be let out. You can see that they failed to release the leeward backstay, so when they tried to dump the pressure on the main to keep the boat upright, it hits the stay and can't swing any further. That leads to them having far too much pressure on the main, and hence the capsize. At 4:34 in this video you can see both backstays clearly, and at 4:43 you can see the sail hung up on the stay. They were trying to release it, but couldn't because of that simple mistake.
🌬🌊You are channeling the spirit of Bernoulli. When you made the sailing-is-all-about-flying analogy, a lot of things clicked in my mind and I appreciate the analysis, Capt!
I live in AKL and the crash used up a reasonably large amount of time in the nightly news reports. It was great to see the other teams assist the team with the situation.
I think you spoke of the incident every accurately. It is phenomenal the degree of drag reduction, especially in the rigging wires, how they are formed to reduce drag. Back in the day, we were very concerned if we did not have enough beer on board.
Wonderful lesson on aerodynamics🙂 but the astonished face of that young lady in the audience center right foreground with her hand over her mouth was priceless! No one could have expressed it more poignantly. 😮
With my 13 tons of steel and full keel i wont have to worry about getting over 8 knots, but love the watching the new boats do there thing. Thanks Juan.
Composites are easy to field patch. In factory they use a heat setting resin, cured in an oven. There are UV setting resins and Catylist setting resins. Both of which are field usable. In the composite racecars, most minor field repairs are done with a two part epoxy. (Even if it is built with a heat/ oven resin.)
They race best at top speed and they are very sensitive. The captain knew there was a gust and had to "go for it" or lose the race. Bit of bad luck with the size of the gust. Winds were within regulated norms. Computer controlled, hydraulic (human powered I believe). Hole was caused by inner structure "guillotining" down through the hull when it stalled and slammed back into the water. Only major scructural issue is the the hull repair, entire hull was ultrasounded shortly after they pulled it out. Hydraulics are closed loop and fine, electrical system is toast and will be fully replaced. Apparently all the teams are joining together to assist in repairs and they have all parts and spares needed. A testament to the spirit and camaraderie of the Prada cup teams. By their own words it did not sink as others did because they not longer use or need massive lead ballasts that took old boats rapidly to the locker. Even holed it was so light that with the jib and rafts as floats and patch and a load of pumps they saved it from sinking. When it went over some of the crew actually had to cut themselves out of harnesses to escape as they were under water.
I see your a Americas cup fan to. I've been watching since the USA won it back in the mid 80's. I once had a 18' Solcat catamaran that I sailed on Folsom lake. I sailed it once from Richman to Angel Island on the roller waves. I now sail a 14.2 Capri on Big Lagoon up North of Eureka.
There are two running stays used to support the mast in the aftward direction. One runs the then port side aft quarter and the the other to starboard. The windward one is the one that supports the mast while the leeward is eased to allow the sail to be eased out. The leeward runner was never eased for whatever reason keeping the mainsail from easing out to match the angle of attack of the wind which was now aft as the boat rounded the windward mark. Also it appears a huge gust of wind appeared causing the apparent wind to come more aftward which would require further easing of the sail.So rather than the lift being directed forward, the wind pushed rig over to leeward.
I did a 10-second search and the computer said that the fastest disclosed recorded speed the ac75 has gone is 56 miles an hour. Can you imagine cruising in your 4 million-dollar Fountain cigarette with 4000 horsepower and being passed up by a sailboat?
Thank you for that run down Juan, The aeronautical comparisons between that type saying is frightening to say the least. I had no idea the level they were operating at untill your piece so thanks again.
Great to see that in addition to local safety cover the three rival teams - Kiwi, British and Italian - all pitched in to help the American team. Also one of the crew was heard to say before the manoeuvre (not a misspelling, it's the Queen's English my American friends!) 'Do you really want to do this?'. In the event, perhaps not!
thanks Juan My home town Auckland These boats are awesome They are not so good in light winds they need around 12-15 kts to get up on the foils then 50kts boat speed is not out of the question. Auckland can get quite windy so things could get quite interesting in March when the AM cup challenge starts.
Thx Juan and Pete for your timely and informative review of AC75 Patriot's untimely capsize when in the lead of Luna Rosa. I know your C22 doesn't have foils or wing sails but thought you both did a great job of enlightening your audiance to the amazing technology of the latest Americas Cup boats. One area that is still in question is why the lee running back stay failed to release for the new tack after rounding the mark which keeped the mainsail from reducing lateral effort and contributed to the capsize IMHO. I like you have a passion for sailing and during 80s raced a Toranado Catamaran which didn't have hydra foils but was ultra light construction and would fly a hull and reach speeds nearing 30kts which could end in capsize or pitch pole in an instant if you weren't paying attention. After folding a mast from deflection due to over powering in heavy seas and splitting a rudder thru the rudder stock with resulting round up and flying trapeze ride and crashing into lee hull I've experienced 1st hand how quickly things can get out of control. Let's say a prayer that Dean and the boys can get her back on the coarse and take back the auld Cup. Beautiful Scenery where your vacationing enjoy yourselves.
Thanks for your detailed analysis. I’ve been a private pilot and HobieCat sailer for years and I agree they are very much the same. BTW, you have a lot more than a thimbleful of knowledge on sailing!
The main sail was pinned against the port backstay. The releaser for the port backstay was jammed, preventing the main sail from being eased to depower the boat. The hole is boat is from the battery bank. They smashed through the hull. There is a report that there is also delamination along the keel.
Juan, only software connects the rudder trim tabs and the flaps on the main foils. In the capsize, the leeward running backstay was not released which prevented the mainsail from going out more in that wild bear away as the boat going 40 knots was hit by a 25 mph gust and Dean Barker could not reduce the power in the sail. The crew had about 3 seconds after tacking to start the bear away to good wind and the flying began.
Gave up flying for sailing as the family grew. In sailing you use all your flying skills & training to sail a bost, although everything is slower. Navigation, chart reading, communications, right of way rules, weather (you can even think of the invisible current under your boat like the jetstream over your plane.) It is true that going to windward, one does indeed “fly” the sails (less so off the wing, but shaping the sails to the wind is still important. You play the wind (and currents), just like flying a cross-country or out smarting a gusty crosswind on final. In 2000 we left Annapolis for Bermuda and on to the islands. Dind’t stop cruising until 2007. Unlike flying, you bring your house along with you, so it’s a lot cheaper & you don’t use much fuel. Even at that, we avoided all the expensive parts of cruising. I had two sayings we lived by: 1. A small boat & a suitcase full of money beats a 45-footer tied to the Bank anyday. 2. The view of paradise looks the same from every sized cockpit. We bought a $50k Westsail 32, put about $15k into her to make her cruise worthy, & sold her 8 years later for $50k (around $2,000 per year ownership costs. Like most cruiser we went naked, without insurance. Without a lien holder to please, we figured that if we wrecked the boat we could eat the loss....besides, we’d probably be dead anyway). As a lapsed pilot, I was recently looking around for a knock-about plane, mostly for grass-strips, TNGs & cow-gazing from $1,000 ft fit my dotage. 3rd class meds are going to be a hassle, but LSA prices are so outrageous i”ve about given up, on the idea. Anyway, sorry to go on,. To answer your question, “yes” flying a sail on a boat is very much like flying an airplane wing, but only when going to windward in the sailboat.
Juan, I watched the press interview and the skipper said it took 18 pumps to get it to a position so they could tow her back. Impressive to watch them sail/fly but like other commenters have said I would rather see the old 12 meter yachts go head to head. However times a change!
Call me a relic, but I'd like to see these guys go back and try to race the 12 meter boats from the 60's and 70's as a real challenge :) (the again, I miss the opening scene from ABC Wide World of Sports "The thrill of victory; and the agony of defeat!"). Thanks, Juan, for looking at this, and once again, putting it in understandable terms!
Keep in mind that the foils are operating at essentially the same pitch angle as the hull. So, with the hull pitched significantly nose up, the submerged foil is at a similar positive pitch angle, and will generate a huge upward lift force causing the boat to lift out of the water.
Nice job Juan, especially for a non sailor. My two cents: The rudders on all fast sailboats, but especially these boats are very easy to stall if you apply too much AOA. At 4:44 in your video timeline is when the rudder first starts to stall. I believe, but I'm not sure, that as soon as the rudder stalls not only do you lose lateral control, but you also lose pitch control. We have seen evidence of this in previous races when they have stalled the rudders during various maneuvers. As soon as their pitch control was reduced, the stern fell to the water, changing the AOA of the leeward foil causing it to jump out of the water. The hydrodynamic forces are much higher than the aerodynamic forces on these boats. Thus the boat reacts much quicker and forcibly to the hydro forces, than the aero forces. If someone here is intimately familiar with the stall characteristics of the rudder foil on the AC75 boats, please chime in.
hey juan. a little local update for you from here in auckland nz. loads of auckland companies are offering the required services and expertise for free, and working round the clock to get this boat repaired and back in the water in time. fingers crossed as we are seeing some truly spectacular racing thats for sure. and i gather the boats are getting 3 times wind speed, which is pretty good im told ?
Thank you, Juan, for the excellent analysis of wings on water and in water. The foiling aspect has changed sailing so drastically that it is difficult to stay up to date on the boats. There will probably be a new name for sailing with foils, to distinguish from regular sailing.
Seems like a dance between aerodynamics and hydrodynamics. I think the rudder has less hydrodynamic drag as it lifts out of the water. Very cool engineering technology!
Note when entering the turn boat speed touched 48 kts. "Slowed" to 40 at lift off. The pitchup likely was driven by the Windage of the rig, as the mast is much taller than the boat is long. Repair of the area around the hole is tough as there may be lots of delamination to be identified. These composites are all cooked in big ovens, so cure time can be quicker.
You breakdown of what happened is the best I have seen Juan. American Magic have decided to bypass the round robin series and have 11 days till their semifinals. All teams including Defender Team New Zealand have offered anything they need.The sailing community like a lot is very tight and will help. During the rescue attempt and long trip to town Team New Zealand supplied Pizza and soft drink. When asked about it at the press conference The American Skipper laughed and said it was appreciated but they could have send McDonalds and Budweiser.
My dad, a pilot as well, also being one of these yahoo's, that dragged me from Rigatta to Rigatta, let me share with you Juan. This is the sport for boys with more money than sense. Take it from someone who has spent many hours clinging to the running boards of turtled boats. Capsize is the sure-fire effect when the push of captain's ego is higher than the sail's angle of attack divided by the speed of the wind minus the speed of the wind coming out of the captain's screaming mouth during a tack. I think the race is over with a hole that big.
My immediate reaction was “what the hell, it’s about boats” but that was a 100% educational video which I really enjoyed and learned a lot from. Thanks.
Matt Lewis had it right on. The port side backstay was not released in time and the main sail could not dump its wind load. You can see this in the video.
Great analysis and you are correct; there are a lot of similarities between sailing and flying. When I first started sailing, I was pleasantly surprised how much they had in common.
I suspect that this will probably happen again. The main sail is somewhat locked in and cannot be quickly release to alleviate the sudden pressure caused by the gust of wind. I've sail in extreme winds(35-40 kts) on small 15 ft. with three of us on a reach, I had to control the main sheet in my hand dumping wind as the pressure changed. We were going 30 kts. and have never ever gone so fast. Young and crazy those two late teenager boys with me were quite scared and were glad when we made it back in the breakwaters. The rip to the oil platform and back was accelerating. Lots of Love
The New Zealand marine industry has been at the cutting edge of composites since they first introduced them to boat construction. You couldn't be in a better country in te world to execute a repair on this hull in four days. They'll have the skilled tradespeople and materials on hand before the boat has even dried out.
The mainsail is trimmed using batons that are flattened or straightened. This is as important as the traveller's job to swing the main over. The large wind gust at the time of the maneuver and the sudden change in wind direction contributed to this plus the port running back not being released. It's never just one factor.
Great commentary as a sailer of over 50 years and lover of aviation you are right on , sails are wings and when your and Angle of attack into the apparent wind exceeds the laws of aerodynamics you stall . These are extreme boats sailing at the very edge of what’s possible. The rudder design looks to me to be too narrow and it loses an ability to allow the pilot / helmsman to get her to luff up into the wind fully so the power of that gust can be dissipated quickly It’s one of the first things you learn in your 8 foot sailing dingy get rid of that gust as fast as possible don’t fight the stall and recover by easing off the wind as soon as you have unloaded the effects of the gust. I would always tell anyone wanting to learn how to fly take sailing lessons I. A small boat firs and learn to feel fully what wind can do close up
One other factor to take into account is these "yachts" don't heel as a normal yacht would about the center line as the points of contact with the water are offset (rudder and one foil) so when they pitch about the line between the rudder and the foil in the water. Hence you will see them pitching up and down quite a bit and this needs to be controller but the "flight crew" and loss of control will lead to a nose dive or a flight to the sky. Emirates team New Zealand lost control a week or so ago and nosedived while training, no damage in that incident . Keeping these flying flat and low is real art in gusty conditions while travelling at 45 knots or over 51 mph.
We would pitch-pole our Hobiecat for fun & all the power boats would rush to save us. We were young & fit & two of us could right it. Next life - - - Sailing.
Did you know that Alexander Graham Bell, was also a poineer in hydrofoil boating? Back in the turn of the 20th century, Bell was living in Nova Scotia, Canada, and after seeing an article on hydrofoils in Scientific American in 1906, Bell began hydrofoil experiments in the summer of 1908. Through his experiments, and a visit to another hydrofoil pioneer, Enrico Forlanini to ride in his hydrofoil in Italia, Bell working with Casey Baldwin eventually created the HD-4 hydrofoil boat. This boat later went on to establish a world marine speed record of 114 km/h (62 kn; 71 mph), which stood for two decades.
nice, thanks for the info. I've also heard that Bell had something to do with the invention of the aileron. there was a professor at Stony Brook U here on Long Island back in the 70s and 80s who put foils on catamarans and even made a foil for windsurfing ca. 1983.
@@asquare9316 Bell was a real smart guy, and his intrestes were wide and broad. Probably one of the greatest inventors of the past 200 years. BTW. I was around Stony Brook U back in the early 80s, visiting a female freind, and hanging out in the Science Fiction Forum, and going to I-CON.
It's been noted elsewhere that the reason they couldn't sheet out the mainsail is that the running backstay on the port side was still taut. The main was pinned between the two backstays (or whatever they call them nowadays) and there was no way not to stall it deeply. It seems like a procedural error. edit: Adding that, on fast sailboats the apparent wind differs greatly from the true wind, at least until you suddenly lose most of your forward speed. Then the AOA of the sails suddenly gets dramatically greater and you're in deep stall in less than a second. The apparent wind is of course the sum of boat velocity and true wind; that boat was probably going faster than the true wind so we're talking about a nearly instantaneous AOA increase of 30 or 40 degrees.
I was just watching the races for the first time ever on TV a couple days ago. Thanks for the insight, I knew nothing at all about them, just a few 'guesses'. LOL --gary
Think of the main sail as a rudder. It is much larger than the actual rudder in the water. Trimming the main sail turns the boat as much as the rudder in the water. They could not release/ease the main sail due to the stuck running back stay. This led to the boat not being able to turn left, downwind. This forced the boat to turn right or “round up”. The hole in the boat was created by a large battery pack becoming dislodged and then departing the yacht by creating a giant hole! They are going to skip next weekends event. This will give them two weeks to get the boat fixed.
Great description of what cause the boat lift and flip over. The speed that these boats go today make the days I was sailing look like a C 47 competing against a Gulf air.....
Juan, Message from a sailor. The reason why the American boat got out of control is because the leeward back stay was not released. If you look closely, early in the manoeuvre , (in fact as the boat starts bearing off after the tack), you will see the trailing edge of the mainsail, instead of falling off a bit, is instead curling up and holding the whole upper sail basically dead amidships. Therefore backstay is not only was stopping the mainsail from being eased but also keeping too much power near the top of the mainsail which overpowered everything. Just a bit sad really. I used to be a backstay boy years ago when I first started sailing, and woe on me if I didn't release that backstay during a gybe or tack. Cheers.
@@blancolirio I believe that it was not obviously mentioned. Actually during the incident, when I saw the first clip of it, I could swear that someone in the crew shouted about the backstay just as the boat was going out of control. You understand that crew communications during the racing are broadcast at the same time a commentators. Cheers
Hello Juan.
From a Kiwi aviation and sailing fan here who loves your channel. Wonderful to see that some US viewers are getting exposed to this exciting racing happening on our doorstep.
As a yachty and America's Cup fan, I wanted to share some tweaks or corrections to your explanation of how these boats work.
The main foil arms can be cranked (canted) vertically up and down about a fore-aft axis. Looking at the boat from the stern, and considering a normal keel straight down position to be zero degrees, the foil arm sits out at about 70 degree cant angle when in the water (on leeward side of the boat) and about 120 degrees when lifted out of the water (on windward side of the boat). This canting is the only direction of movement permitted on the foil arm, so some of the movements you thought you were seeing were just camera angle or perception, but didn't actually happen. The arms can't be steered like a rudder, or raked, like in the previous America's Cup catamarans where they used foil rake for flight control. The foil cant angle is used by the flight controllers to control the boats ride height. As you noted, they try and ride them as low to the water as possible to seal off the aerodynamic pressure between sail/hull and water. They also use the cant angle to adjust the heel of the boat, or in aero terms, the bank of the boat. Unlike regular monohulls that heel to leward (banking away from the wind), the AC75s can be canted to heel/bank in to the wind.
Flight control in these boats is achieved in two parts.
The first part of flight control is through trailing edge foil wing flaps, that can be used to increase or decrease lift on the wings. Note that without foil rake permitted, choosing the overall angle of attack for the immovable part of the wings is important, as if your wing doesn't naturally generate enough lift to fly the boat, then more wing flap angle is needed to generate sufficient lift, however this also creates extra drag. (This is believed to have been a cause of Ineos UK teams flight issues pre Christmas). At low speeds (sub 20 knots) the flap will be used to increase lift, then would progressively reduce to neutral. The boats spend a lot of time at 35-40 knots so the wing lift profile is likely to be optimized for these speeds. However the boats semi frequently operate at 40-45 knots and are believed to be capable of up to 50 knots. At these speeds the wing flaps could be used to negate excessive lift off the main wing structure, however most teams seem to be controlling excessive wing lift with the second part of flight control.
The second part of flight control is with rudder rake. The rudder wings have no flaps, however the whole structure can be moved with rake. Raking the rudder backwards would angle the rudder wing downward, pitching the bow of the boat upwards, and therefore as a consequence also changing the main wing angle of attack to a slightly more pitched up position. Raking the rudder forwards angles the rudder wing upwards, creating lift at the stern, and therefore pitching the bow of the boat down, and again as a consequence changing the angle of attack of the main foil wings slightly downwards.
At high speeds (over 40 knots) which we were witnessing here (I believe Patriot had rounded the mark at about 44 knots), the rudder rake is being used to generate lift, and pitch the boat downward to try and keep the whole boat lower in the water and reduce the lift generated from the main wings. However a side effect of rudder lift is the reduced rudder remaining in the water, and therefore reduced steering control.
High speed mark rounding are an inherently dangerous manouvre in these boats as you have less rudder steerage and control at exactly the time you are pushing the boats to the limits of it's ability to turn/yaw.
In the case of this accident Patriot was rounding the top windward mark approaching on port tack sailing into the wind, and attempting to tack to starboard, then bear away and ultimately do the ocean equivalent of a hairpin u-turn and head straight back the way they had come from.
Just before the mark they tacked through the wind (crossing the boat at the bow) to change to starboard tack. This requires foil canting, initially to lower the previously airborne port foil, at which point the boat sails briefly on two foils, then when under control, raise the starboard foil to reduce drag. The foil canting is done with electrically powered hydraulic actuators that take 15 seconds to recharge after a full foil cant. So having done this tack move, Patriot was committed to the foil cant positions for at least the next 15 seconds, but it was game over before then.
Having completed the tack to starboard, the Patriot was then rounding the top windward mark and bearing away (not luffing as you mentioned). During the bear away, the boat changed its angle to the wind from a point (facing the wind) to a reach (sailing across the wind). The reach position naturally powers up these AC75 boats, and when trying to accelerate at the start or in light airs, the helmsman sails at a pure reach of 90 degrees to the wind direction to try to get maximum power.
At the same time, there was an increase in the windspeed measured as increasing from 18 knots to 23 knots. The recipe ingredients for an accident were all there. The boat hydraulics on timeout, while the boat is in the maximum acceleration angle to the wind, just as a gust hit. The boat speed was increasing and the helmsman was attempting to pitch the boat down, by rudder raking, with the afore mentioned side effect of reduced rudder in the water and steerage. The rigging including the running backstays others have mentioned had been set up for upwind sailing on port tack, then briefly starboard tack, and had not been eased.
The boat was fully powered up, and although they'd tried to ease the jib and the main, because of the reaching wind angle, and the running backstay preventing the main from easing, the sails were overpowered. With the speed increase, all the foils and wings were generating lift, and up she went.
Things that could have prevented the accident.
1 Round the other top mark, so no tack was required, but just a simple bear away. (Not chosen as they were under pressure to stay ahead of Luna Rossa, and they chose the favoured mark).
2 Depower the sails before the mark rounding and remain on dual foils until the new boat/windand therefore required foil/wing/rudder/rake positions were known. Not chosen for same reason as 1.
3 Bear away more quickly to 180 degree to the wind. Sailing true downwind massively depowers these boats. World Champion sailor Phil Robertson believes this is the approach they should have taken, but because of the complexity of the manouvre they couldn't make it stick.
Anyway like all Kiwis, including defenders TeamNZ, I wish American Magic all the best and hope that they can get Patriot fixed in time to play a part in the Prada Cup semi finals in just under a fortnight.
Best summation of what happened thanks Matt
I don’t know anything about yachts and only a little about aircraft but whatever the cause, even if someone did not pull the right lever, Juan, you seemed to describe the aerodynamics of what was happening and why in real time. Good job.Your followers enjoy your no nonsense commentary.
Enjoyed the sailing analysis! As the past VP of a sailboat company, I was always amazed at the percentage of pilots that bought our boats. Sailing is flying but you can have a beer in your hand while sailing.
Yes it is similar. I am not a pilot ,but have sailed for 50 yrs. Often while watching your plane videos things you say or explain make a lot of sense to me because of things I have learned sailing. I sail 1 person Tail draggers 12 to 16 foot type boats. Easy to buy and learn and first time out in a strong wind you will go for a swim. You need to learn to feel the wind and start your corrections almost before others realize a change is happening. AS always thanks for a great video.
Hi Juan. Fun to watch. One factor missed by your report but covered by commentary at the time was the leeward backstay was not released which didn’t allow the mainsail to be depowered which may have prevented the capsize. Also sailing still uses “port” and “starboard”. Great channel!
These things don't really seem like boats anymore. Crazy technology. Thanks Juan
Yeah, they are amazing. Crazy but quite beautiful. Un-expected but great footage from Juan.
I say let’s go back to the 12 meters. Those were real boats and fun to watch.
@@jamesknuckey1332 Nope. Those 12 meters were beautiful, stable but slow and heavy displacement boats. There has been a foiling revolution over the past ten years, with small dinghies, catamarans and even kite boards and windsurfers going to foils. Single-handed ocean sailors are now ever more using foils. The New Zealanders established foiling monohulls as the America's Cup class, partly to foster development which can extend to standard cruising and racing boats. The America's Cup has become a much more exciting and accessible spectacle for the public, especially on TV and the Internet, so much more money has flowed into it. I wonder how this will affect the 2.4mR class, which are scaled-down little 12-metre-like boats one sits in to race, therefore very suitable for paraplegic sailors, but very sedate... people are coming up with more exciting foiling alternatives www.2punkt4.de/en/2017/04/01/foil-end-2-4mr/ :-)
@@jamesknuckey1332 real as in real slow.
@@roderickcampbell2105 Is the development that goes along with the current boat designs really "amazing"? It has come down to a material battle and everything happens so fast that luck is also a big factor (the wrong wind gust in the wrong millisecond, like seen in this example). Compare that to the Vendée Globe: there is also a huge technical aspect, but the human element (endurance, mental power, smart decision-making... things you can't buy with money) is much more prominent. These are the real heros and in my opinion such a regatta is much more exciting, especially the one this year!
Whether it’s boats or airplanes you have a good way of explaining things so the common person can understand what’s going on great job
Juan, as a racing sailor, I was very impressed with your explanations. I know less than you about these flying boats but everything you said makes great sense to me.
I didn't realize this channel could get any better. Thank you for the spot on reporting and analysis as per usual! Have a great week.
Now you're in my wheelhouse Juan!. The maneuver they were attempting to execute was a "tacking bear away". Essentially, going from an upwind point of sail, immediately to downwind. Ideally, you would tack, let the boat stabilize, and head down wind gradually. This was a risky maneuver in gusty conditions, and they knew it going in. An aircraft analogy might be an unstabilized approach.
They had 11 days to repair the boat, not 4. The hole is the easy part of the repair. The hard part, as others have pointed out, is the electronics. Fortunately, they have spares. The trick is getting them installed and dialed in, in time. The hydraulics apparently are fine.
Though they claim that nothing exited the boat, I'm skeptical. I think there may be one very large battery sitting on the bottom of the Gulf. It's hard to explain that hole punched through carbon fiber, and a complete piece of carbon fiber being found floating in the water otherwise! IMHO.
Oh... and these boats don't have a "keel". They rely entirely on the hydrofoils for stability, even when sitting still ( both deployed).
ruclips.net/video/ah5V8RHE1_Y/видео.html
Thanks Carl! We're these guys tacking when they did this? What would have been a less risky course of action? Thanks Juan.
I like your battery theory.
I wonder if the missing battery will fit through that rectangular hole :)
@@blancolirio Yes, first they tacked. Barker (the skipper) wanted to go around the left marker, because there was more wind on that side of the course. To do that, they had to tack through the wind (the wind shifts from one side of the bow to the other, as do the sails) round the upwind mark, and head down wind (bear away). Basically a180° turn. Not a big deal in medium conditions and stable wind, but risky if it's gusty. Everything has to go quickly and smoothly.
The alternative was to go around the right mark and simply bear away.. That way, the wind stays on the same side of the boat as you turn down wind. It's less complicated, and less can go wrong. Of course, it would have temporarily put them on the right side of the course, with less wind.
This video from the cockpit shows them approaching the mark. You can hear a crewmember suggesting that bearing off would be safer, and Barker insisting they proceed with the tack! You can see the tack as the sails shift from one side to the other, Then....BLAMO!!!
ruclips.net/video/ah5V8RHE1_Y/видео.html
@@carlwilliams6977 Good analysis Carl. The tack went well.... it was the "bear-away" that got totally out of hand. :) You know what would have fixed that? A keel, lol
Looks like Captain Pete has found a new hobby! As a sailor who turned pilot, I can tell you the similarities between the 2 are incredible. Aerodynamics, weather, navigation, stability. Turbulence is just invisible swell/waves. And both require 100% concentration meaning you can (have to) leave all your day-to-day problems back on ground/shore until you are done playing about! Great mental releases
As an American, I'm rooting for the Brits this year. Just because I saw they hadn't won it before.
This was definitely a surprise video from the Blancolirio channel. I like surprises.
As a professional sailboat captain that watches your channel i was first impressed by your coverage of any sailing incident, was further impressed by the analytics, then further impressed by gaining some insights! My only comment is in sailing we have velocity headers when entering wind shadow areas and thus creating stalling on aero surfaces, then can quickly return when exiting the shadow area, hence some backwinding of sails when this happens, nevertheless stalling is still appropriate😁😎
Great analysis Juan, from a different perspective from the yachties. A few things I've gleaned (not a sailor myself):
The hole in the hull was 'guillotined' by the internal support structure when it crashed down
They have 11 days until the semi final, I don't think they're even trying to race this weekend.
They have a complete set of electronic spares.
All the other teams are offering resources to get them back in the competition.
The British boat has support from the Mercedes F1 team (aerodynamics), so top quality aero, computational analysis, carbon fibre construction etc. The US boat has Airbus as a sponsor.
All those lines you saw with the sail removed are AFAIK not outside the sail, so, no drag (some are). There's apparently a very complex system to shape the wing/mast to achieve the desired power for each manoeuvre. As you said, they fly low to reduce bleed between high and low pressure
The boats are designed to fly with the mast vertical, it's not clear to me which way it should turn to reduce pressure on the sails when it got caught in a gust and started to heel. I thought go left, or loose off the sail to catch less wind but... (not a sailor myself).
Great commentary- As a PPL and sailor of (small) yachts I think your explanations are great! 👍
First of all a salute to Cap'n PiP.
Thanks JB. Interesting design and great information and comparison to an aircraft's operation.
Take care and fly safe. 🤟🏽🖖🏽
Love that you're covering America's Cup! I'm an avid fan of flying and sailing. Thank you and please keep it up!
Well that was fun to watch and hear your take on it. Glad you took a chance and hit “upload” with this one.
I think what made this episode work; focused on the evidence, a bit of interpretation (but importantly, no speculation since it’s peripheral to main expertise of blancolirio), and put in a good bit of news about the incident which I hadn’t received. Rock on brother!
Great review of the incident, shows that they all are balanced on a knife (aerofoil) edge all the time when 'foiling'. But, in general the most remarkable thing about these boats is that they can get a speed of over 30kts in 10kts wind, 40kts + in 15kts wind, just amazing ..!
Juan, I’ll say it again you give a better analysis from 100’s of miles away then the media can due at the scene.
Appreciate the quality of your videos.
I didnt know you watched these too. Glad to see an in-depth explanation from an aviation angle!
Great overview Juan. Being both a pilot and a racing catamaran sailor, you are on point with the comparison of fluid and aerodynamics. As some have mentioned, many miss the days of seat of the pants, tactical sailing in the 12m boats of old. Your tactician was held in revererance.
With that said, the integration of electronics, while needed with the speed forces generated, will come with lessons such as these. This could have had a very unpleasant ending as the boat became airborne. Ask me how I know.
Pray that none of these sailors/test pilots get seriously injured as they test the limits of wind and water.
Keep up the great channel- you've convinced me to become a patreon!
Blancolirio
To bring you closer to the aero/ hydrodynamic challenge of these boats:
- Sailing upwind they are tacking against the wind with a quite low AOA in the sail, high aero speed due to wind and boat speed are adding to speed through the air (roughly 4 to 5 times the wind speed)
- Sailing downwind they are gybing with the wind again low AOA, just the windspeed is subtracted from the boat speed. You have roughly double to triple of the windspeed around the sails, still a lot of lift to drive the boat but much less resistance. The boats are even faster.
- the very most critical maneuver is changing between upwind and downwind, it is called bearing away. You have this high 4 times windspeed in the sails and due to the boat turning the AOA is increasing. This generates enormous momentum accelerating the boat and pressing the mast leeward.
Those guys did this maneuver in the worst possible moment: During bearing away the wind gusted from 15 knots to 24 knots which caused a loss of control (rudder stalling, boat healing over, ...)
From this point on they are passengers, just the boat has a speed of more than 45 Knots with a very lot of energy able to break the structures.
The hull's take off is not generated by aerodynamics from the hull itself, it is generated from the leeward foil: The healing of the boat lifts the middle of the boat upward, the rudder with the foil has to stay in the water. The consequence is a radical increasing AOA the leeward wing interacting in the water. This causes the boat to jump.
Once completely in the air: game over..., it is a boat. without anything in the water, there is no stability left over.
Quite fascinating (and intense) regarding all the mechanical forces at play... definitely looked as though the bow of the boat pitched up/porpoised upward (?) much more aggressively than one would ever expect to see. Would such a severe upwards pitch have more to do with those responsible for controlling the position of the sails, more to do with those responsible for controlling the hydrofoils, or the improper control/balance of both systems(?)
@@__WJK__ Those responsible for sail control are responsible for not healing over either side and forward power, very complex with quite a number of controls involved.
Those responsible for "flight control" have to keep the flight height in a narrow band and minimize track in the water with quite a number of control parameters as well. They are heavily influenced by speed and healing.
Not to forget the helm supported by tacticians being responsible for the right AOA in the sails and so the speed as well, finding the shortest and fastest way around the course and the tactic to beat the other boat.
all aspects have interdependencies ..., a very complex scenario to run a yacht having only two connection points in the water.
Thank you so much for the comment, Peter. Great stuff
Hi guys from nz I am stoked the world is Reeee even interested after all that's been going on......This channel is one of my favorites because he knows what he's talking about and he's a good guy 😉 regards NZ
Thanks for this. I couldn't work it out I though they were tacking upwind, but yes bearing away as you explained I can see more clearly what happened 👍
Another possibility - the leeward backstay wasn’t released after rounding the mark (human error). This made it impossible for the crew to release the mainsail and de-power when the gust of wind hit.
"Another" possibility? That was the first possibility that the commentators of the race mentioned.
An interview with the skipper indicated that they were already well on their way to the crash before the backstay became an issue.
Sure looks like it !
Sure seems like there’s a fine line that gets these boats into trouble and no major de power method that can save you in all cases. I feel that without a keel of some sort there just isn’t any natural tendency to round up. Can you even feel any weather helm on these things?
@@ben3989 I don't know about foiling boats, but I do windfoiling (foil windsurfing) and on a windsurfer in normal mode the forces are mostly lateral so you feel something akin to weather helm when going upwind (spent over 40 years steering racing sailboats) but when foiling, the forces are mostly vertical so I don't think they feel much weather helm on these boats. Just my opinion.
Good stuff, Juan!
They actually were desperately trying to stall the main sail. That huge microburst happened just after rounding the mark and they were unable to release the leeward backstay in time to de-power the main. These boats can't use a traditional centerline backstay because of the shape of the mainsail. So they are equipped with two backstays and they normally release the leeward one at the same time they tension the windward one. If you pay attention to the boat speed you'll see that they actually generate a significant portion of their own apparent wind. I think they were around 47 mph at the start of that event and you can add that to gust front. We're talking about a Category 1 wind speed over the deck. :-)
It is my understanding that the rudder is also fitted with control surfaces like elevators on an aircraft. The pilot uses them to adjust the angle of attack for those foils midship.
The thing about leeward backstay staying tensioned is correct. It prevented depowering the main sail and this resulted in heel / roll to left. As the main lifting foil is not on the centerline as the rudder lifting foil any rolling motion induces pitch motion. Since the heel/roll went out of control so did the pitch and with tjat the angle of attack of main hydrofoil which launched the boat out of the water in the hunt for the red october style.
Juan, excellent job reporting the news about "PATRIOT" the American entry AC75 (75 foot foiling mono-hull) for the 36th edition of the America's Cup from Auckland, New Zealand. The challenger series of racing titled the PRADA CUP currently taking place DOWN UNDER includes Great Britain and Italy in addition to the American challenger sponsored by the New York Yacht Club.
The crew of Patriot took an unexpected salt water bath on this mark rounding. Upon further review of the video you will notice the port side running backstay was not released as it should have. There is clear evidence that the main sail is pinned against the running rigging. Normally , if the mainsheet is released that would allow the mainsail to feather (releasing the pressure) in the gusty wind conditions allowing for some control of the vessel. During this maneuver the Mainsail was not able to feather as needed. Keeping in mind that this high performance water craft was reaching a speed close to 50 MPH balancing on 2 unstable points on a liquid base. (The ocean) Things happen very very quickly for the crew and helmsman. The canting wing/foils weigh in at just under 1.4 tons each. One on the Port side and one on the Starboard side. They are designed to provide the "righting moment" or "counter balance" against wind pressure and of course the lifting of the yacht out of the water on the submerged foil once enough velocity is reached. This is how you turn a displacement racing yacht into a flyer. With only 8 -12 knots of wind the boat can reach speeds over 40 knots. Yes, a sail on a boat is an aircraft wing turned vertically. Same rules of physics apply. The difference is when you crash (KABLAMMO) you get wet instead of something worse. This design of the AC75 is cutting edge. Everyone involved is learning minute to minute and day to day. Thank you for reading. MC
Also a sailor here. I have a Catalina 34. My Grandfather who turns 102 this week flew Catalina’s in WW2. We talk fly and sailing together . Same thing ...
I've been a pilot and a sailor for almost 50 years, never understood how these Cup boats worked until your video, thanks for the explanation!
Great job!
.. started sailing when I was 5 and just like you said it is all the same principles of aerodynamics.
Here’s another similarity of sailing to flying ... it is really pretty easy UNTIL you get close to land.
👍🏼
Side side side note rumor mill is saying that it was the mechanism that operates the hydrofoil that punched that hole during the impact of that 17,000 pound hull back into the water.
I believe the technical term eummf is translated to inertia for us laymen. I might be wrong.
Drag in the water is a huge factor in sailing (vs. flying). Once you're doing foiling like this sailing is no longer about just using the wind but a thin tightrope balance between the huge aerodynamic control with the sail and the very delicate hydrodynamic control with the foils and rudder. When the stern of this boat hit the water after getting lifted it basically hit the brakes, tripped over the stern and slammed back down. Another thing that happens in these cases a lot is that the the bow hits the water first and the boat pitchpoles, many of those examples on video if you want to look.
Hi Juan, yes, it's 'basically aerodynamics', but the word you're looking for is hydrodynamics. Seawater is 800 time more dense than air. Adjust control surfaces and strength members for that and the rest is pure physics and racing fun. I was glad to see you put together a video about this event. Very apt crossover for your channel. Stay safe out there. Cheers, D.
Good afternoon... These new boats are quite impressive, but color me old fashioned, i sure miss those 12 meter yachts with secret keel designs.I’m one of the many Pilot Sailers....James
Right. I'd be excited to watch modern J boats race, but these things are just a technical exercise, this isn't sailing I want to see.
these things are awesome pieces of technology, but I agree,, it's all about boat speed and, to me, although much slower, the 12m or IACC class boats allowed for much closer, much more tactical racing. I miss the battles at the start that there used to be in the old AC matches. another pilot (well, student pilot) sailor here.
Sailing and foiling are basically separate sports now.
I was around Ultimate 30 racing in the late 80's, Turtle Up was part of the attraction. Like Indy, it promotes R&D in Marine Engineering, a good thing.
@@johngilbert1325 It's still sailing. Technology has almost taken over, but you still have to read the wind shifts and handle the gusts. As for foiling, I wish it had come in earlier in the A-Class catamaran. Sailing an A-Class upwind, out on the wire, is Zen for sailors. Unfortunately, I had to give up sailing A-Class before foiling. I can imagine how much doing it on foils would add to the experience, but I won't experience it. ruclips.net/video/v80uH1I3oMU/видео.html The guy with white cap is Glenn Ashby, who controls Emirates Team NZ with his magic box.
Man that's an excellent job on that. I wasn't even aware that the boats had progressed that far another great job Juan
Luffing and Stalling:
In aerodynamic terms, a sail luffing is sort of the opposite of a sail stalling. A wing or sail stalls when the angle of attack is too great. Luffing -- the sail flapping loosely in the wind -- occurs when the angle of attack is too small.
Correct, sheet in or bere away 👍
to add some more detail as to why they heeled so far over: these boats have what are called running backstays, where there are two wires running from the top of the mast to the back of the boat. Each wire goes to one of the back corners. Those 'running' backstays have to be loosened on the downwind side to allow the sail to be let out. You can see that they failed to release the leeward backstay, so when they tried to dump the pressure on the main to keep the boat upright, it hits the stay and can't swing any further. That leads to them having far too much pressure on the main, and hence the capsize. At 4:34 in this video you can see both backstays clearly, and at 4:43 you can see the sail hung up on the stay. They were trying to release it, but couldn't because of that simple mistake.
🌬🌊You are channeling the spirit of Bernoulli. When you made the sailing-is-all-about-flying analogy, a lot of things clicked in my mind and I appreciate the analysis, Capt!
Whether its air or water, its all fluid dynamics. Great analysis. Thanks.
Great analysis Juan as always, I watched it live and it was VERY spectacular.
I live in AKL and the crash used up a reasonably large amount of time in the nightly news reports. It was great to see the other teams assist the team with the situation.
Excellent analysis and I don't know anything about these boats. Enjoyed. Good job.
I think you spoke of the incident every accurately. It is phenomenal the degree of drag reduction, especially in the rigging wires, how they are formed to reduce drag.
Back in the day, we were very concerned if we did not have enough beer on board.
Wonderful lesson on aerodynamics🙂 but the astonished face of that young lady in the audience center right foreground with her hand over her mouth was priceless! No one could have expressed it more poignantly. 😮
With my 13 tons of steel and full keel i wont have to worry about getting over 8 knots, but love the watching the new boats do there thing.
Thanks Juan.
Composites are easy to field patch. In factory they use a heat setting resin, cured in an oven. There are UV setting resins and Catylist setting resins. Both of which are field usable. In the composite racecars, most minor field repairs are done with a two part epoxy. (Even if it is built with a heat/ oven resin.)
They race best at top speed and they are very sensitive. The captain knew there was a gust and had to "go for it" or lose the race. Bit of bad luck with the size of the gust. Winds were within regulated norms. Computer controlled, hydraulic (human powered I believe). Hole was caused by inner structure "guillotining" down through the hull when it stalled and slammed back into the water. Only major scructural issue is the the hull repair, entire hull was ultrasounded shortly after they pulled it out. Hydraulics are closed loop and fine, electrical system is toast and will be fully replaced. Apparently all the teams are joining together to assist in repairs and they have all parts and spares needed. A testament to the spirit and camaraderie of the Prada cup teams. By their own words it did not sink as others did because they not longer use or need massive lead ballasts that took old boats rapidly to the locker. Even holed it was so light that with the jib and rafts as floats and patch and a load of pumps they saved it from sinking. When it went over some of the crew actually had to cut themselves out of harnesses to escape as they were under water.
I see your a Americas cup fan to. I've been watching since the USA won it back in the mid 80's. I once had a 18' Solcat catamaran that I sailed on Folsom lake. I sailed it once from Richman to Angel Island on the roller waves. I now sail a 14.2 Capri on Big Lagoon up North of Eureka.
There are two running stays used to support the mast in the aftward direction. One runs the then port side aft quarter and the the other to starboard. The windward one is the one that supports the mast while the leeward is eased to allow the sail to be eased out. The leeward runner was never eased for whatever reason keeping the mainsail from easing out to match the angle of attack of the wind which was now aft as the boat rounded the windward mark. Also it appears a huge gust of wind appeared causing the apparent wind to come more aftward which would require further easing of the sail.So rather than the lift being directed forward, the wind pushed rig over to leeward.
Thanks Juan For the great explanation as always!
I did a 10-second search and the computer said that the fastest disclosed recorded speed the ac75 has gone is 56 miles an hour.
Can you imagine cruising in your 4 million-dollar Fountain cigarette with 4000 horsepower and being passed up by a sailboat?
..stellar as usual Juan !..thankee!..tak! from Bornholm,Denmark
Thank you for that run down Juan, The aeronautical comparisons between that type saying is frightening to say the least. I had no idea the level they were operating at untill your piece so thanks again.
Great to see that in addition to local safety cover the three rival teams - Kiwi, British and Italian - all pitched in to help the American team. Also one of the crew was heard to say before the manoeuvre (not a misspelling, it's the Queen's English my American friends!) 'Do you really want to do this?'. In the event, perhaps not!
yes, and the person that asked that was a Brit and the helmsman is a Kiwi. Go figure. Please bring back country of origin rules for AC.
thanks Juan My home town Auckland These boats are awesome They are not so good in light winds they need around 12-15 kts to get up on the foils then 50kts boat speed is not out of the question.
Auckland can get quite windy so things could get quite interesting in March when the AM cup challenge starts.
Great report and analysis Juan! These cup boats are amazing.
As a sailor, thank you for your comparison of the sail shape to a wing foil. These new boats bloody fast but interesting to watch
Thx Juan and Pete for your timely and informative review of AC75 Patriot's untimely capsize when in the lead of Luna Rosa. I know your C22 doesn't have foils or wing sails but thought you both did a great job of enlightening your audiance to the amazing technology of the latest Americas Cup boats. One area that is still in question is why the lee running back stay failed to release for the new tack after rounding the mark which keeped the mainsail from reducing lateral effort and contributed to the capsize IMHO. I like you have a passion for sailing and during 80s raced a Toranado Catamaran which didn't have hydra foils but was ultra light construction and would fly a hull and reach speeds nearing 30kts which could end in capsize or pitch pole in an instant if you weren't paying attention. After folding a mast from deflection due to over powering in heavy seas and splitting a rudder thru the rudder stock with resulting round up and flying trapeze ride and crashing into lee hull I've experienced 1st hand how quickly things can get out of control. Let's say a prayer that Dean and the boys can get her back on the coarse and take back the auld Cup. Beautiful Scenery where your vacationing enjoy yourselves.
Thanks for your detailed analysis. I’ve been a private pilot and HobieCat sailer for years and I agree they are very much the same. BTW, you have a lot more than a thimbleful of knowledge on sailing!
The main sail was pinned against the port backstay. The releaser for the port backstay was jammed, preventing the main sail from being eased to depower the boat.
The hole is boat is from the battery bank. They smashed through the hull.
There is a report that there is also delamination along the keel.
Juan, only software connects the rudder trim tabs and the flaps on the main foils. In the capsize, the leeward running backstay was not released which prevented the mainsail from going out more in that wild bear away as the boat going 40 knots was hit by a 25 mph gust and Dean Barker could not reduce the power in the sail. The crew had about 3 seconds after tacking to start the bear away to good wind and the flying began.
Gave up flying for sailing as the family grew.
In sailing you use all your flying skills & training to sail a bost, although everything is slower. Navigation, chart reading, communications, right of way rules, weather (you can even think of the invisible current under your boat like the jetstream over your plane.)
It is true that going to windward, one does indeed “fly” the sails (less so off the wing, but shaping the sails to the wind is still important. You play the wind (and currents), just like flying a cross-country or out smarting a gusty crosswind on final.
In 2000 we left Annapolis for Bermuda and on to the islands. Dind’t stop cruising until 2007. Unlike flying, you bring your house along with you, so it’s a lot cheaper & you don’t use much fuel. Even at that, we avoided all the expensive parts of cruising.
I had two sayings we lived by:
1. A small boat & a suitcase full of money beats a 45-footer tied to the Bank anyday.
2. The view of paradise looks the same from every sized cockpit.
We bought a $50k Westsail 32, put about $15k into her to make her cruise worthy, & sold her 8 years later for $50k (around $2,000 per year ownership costs. Like most cruiser we went naked, without insurance. Without a lien holder to please, we figured that if we wrecked the boat we could eat the loss....besides, we’d probably be dead anyway).
As a lapsed pilot, I was recently looking around for a knock-about plane, mostly for grass-strips, TNGs & cow-gazing from $1,000 ft fit my dotage. 3rd class meds are going to be a hassle, but LSA prices are so outrageous i”ve about given up, on the idea.
Anyway, sorry to go on,. To answer your question, “yes” flying a sail on a boat is very much like flying an airplane wing, but only when going to windward in the sailboat.
Juan, I watched the press interview and the skipper said it took 18 pumps to get it to a position so they could tow her back. Impressive to watch them sail/fly but like other commenters have said I would rather see the old 12 meter yachts go head to head. However times a change!
Call me a relic, but I'd like to see these guys go back and try to race the 12 meter boats from the 60's and 70's as a real challenge :) (the again, I miss the opening scene from ABC Wide World of Sports "The thrill of victory; and the agony of defeat!"). Thanks, Juan, for looking at this, and once again, putting it in understandable terms!
The patching of the hull is the easy part, the time consuming part will be replacing the electronics.
Yes, the skipper said that.
Keep in mind that the foils are operating at essentially the same pitch angle as the hull. So, with the hull pitched significantly nose up, the submerged foil is at a similar positive pitch angle, and will generate a huge upward lift force causing the boat to lift out of the water.
If Mike Patey was over there, he could fix it in time by himself. There's nothing he can't do with carbon fiber - and he doesn't sleep. LOL
they will have it fixed, these guys are the best in the world at what they do
Back to work!
He will have to not sleep for 6 months to fix Draco.
Absolutely true, and he would do a better design on the hydraulics.
@@asquare9316 I think the crew is mostly chosen for theie Ape like musculature. Not for their knowledge of composite materials.
Nice job Juan, especially for a non sailor.
My two cents:
The rudders on all fast sailboats, but especially these boats are very easy to stall if you apply too much AOA. At 4:44 in your video timeline is when the rudder first starts to stall. I believe, but I'm not sure, that as soon as the rudder stalls not only do you lose lateral control, but you also lose pitch control. We have seen evidence of this in previous races when they have stalled the rudders during various maneuvers.
As soon as their pitch control was reduced, the stern fell to the water, changing the AOA of the leeward foil causing it to jump out of the water.
The hydrodynamic forces are much higher than the aerodynamic forces on these boats. Thus the boat reacts much quicker and forcibly to the hydro forces, than the aero forces.
If someone here is intimately familiar with the stall characteristics of the rudder foil on the AC75 boats, please chime in.
Juan, I assumed that you were not a sailor. My apologies if I was mistaken.
Very cool. Thanks for the vid and the great explanation of the tech, Juan.
Juan, this was a much better explanation than what I have heard from the AC sailors or the media. Well done.
hey juan. a little local update for you from here in auckland nz. loads of auckland companies are offering the required services and expertise for free, and working round the clock to get this boat repaired and back in the water in time. fingers crossed as we are seeing some truly spectacular racing thats for sure. and i gather the boats are getting 3 times wind speed, which is pretty good im told ?
yes, 3 times windspeed, even 4 times sometimes I think, is pretty incredible for a sailing craft.
Thank you, Juan, for the excellent analysis of wings on water and in water. The foiling aspect has changed sailing so drastically that it is difficult to stay up to date on the boats. There will probably be a new name for sailing with foils, to distinguish from regular sailing.
Seems like a dance between aerodynamics and hydrodynamics. I think the rudder has less hydrodynamic drag as it lifts out of the water. Very cool engineering technology!
Note when entering the turn boat speed touched 48 kts. "Slowed" to 40 at lift off. The pitchup likely was driven by the Windage of the rig, as the mast is much taller than the boat is long. Repair of the area around the hole is tough as there may be lots of delamination to be identified. These composites are all cooked in big ovens, so cure time can be quicker.
You breakdown of what happened is the best I have seen Juan. American Magic have decided to bypass the round robin series and have 11 days till their semifinals. All teams including Defender Team New Zealand have offered anything they need.The sailing community like a lot is very tight and will help. During the rescue attempt and long trip to town Team New Zealand supplied Pizza and soft drink. When asked about it at the press conference The American Skipper laughed and said it was appreciated but they could have send McDonalds and Budweiser.
My dad, a pilot as well, also being one of these yahoo's, that dragged me from Rigatta to Rigatta, let me share with you Juan. This is the sport for boys with more money than sense. Take it from someone who has spent many hours clinging to the running boards of turtled boats. Capsize is the sure-fire effect when the push of captain's ego is higher than the sail's angle of attack divided by the speed of the wind minus the speed of the wind coming out of the captain's screaming mouth during a tack. I think the race is over with a hole that big.
My immediate reaction was “what the hell, it’s about boats” but that was a 100% educational video which I really enjoyed and learned a lot from. Thanks.
Matt Lewis had it right on. The port side backstay was not released in time and the main sail could not dump its wind load. You can see this in the video.
wow. this was a change. loved it! thanks so much
Great analysis and you are correct; there are a lot of similarities between sailing and flying. When I first started sailing, I was pleasantly surprised how much they had in common.
haha, I had the same reaction when I first started flying.
Very good stuff. As always you teach about a subject that I have no knowledge. Thank you.
I suspect that this will probably happen again. The main sail is somewhat locked in and cannot be quickly release to alleviate the sudden pressure caused by the gust of wind. I've sail in extreme winds(35-40 kts) on small 15 ft. with three of us on a reach, I had to control the main sheet in my hand dumping wind as the pressure changed. We were going 30 kts. and have never ever gone so fast. Young and crazy those two late teenager boys with me were quite scared and were glad when we made it back in the breakwaters. The rip to the oil platform and back was accelerating. Lots of Love
The New Zealand marine industry has been at the cutting edge of composites since they first introduced them to boat construction.
You couldn't be in a better country in te world to execute a repair on this hull in four days. They'll have the skilled tradespeople and materials on hand before the boat has even dried out.
Great to see you are so multi-faceted !! Am a pilot and a sailor. Thumbs up on the channel from Africa!
The mainsail is trimmed using batons that are flattened or straightened. This is as important as the traveller's job to swing the main over. The large wind gust at the time of the maneuver and the sudden change in wind direction contributed to this plus the port running back not being released. It's never just one factor.
Great commentary as a sailer of over 50 years and lover of aviation you are right on , sails are wings and when your and
Angle of attack into the apparent wind exceeds the laws of aerodynamics you stall . These are extreme boats sailing at the very edge of what’s possible. The rudder design looks to me to be too narrow and it loses an ability to allow the pilot / helmsman to get her to luff up into the wind fully so the power of that gust can be dissipated quickly
It’s one of the first things you learn in your 8 foot sailing dingy get rid of that gust as fast as possible don’t fight the stall and recover by easing off the wind as soon as you have unloaded the effects of the gust. I would always tell anyone wanting to learn how to fly take sailing lessons I. A small boat firs and learn to feel fully what wind can do close up
One other factor to take into account is these "yachts" don't heel as a normal yacht would about the center line as the points of contact with the water are offset (rudder and one foil) so when they pitch about the line between the rudder and the foil in the water. Hence you will see them pitching up and down quite a bit and this needs to be controller but the "flight crew" and loss of control will lead to a nose dive or a flight to the sky. Emirates team New Zealand lost control a week or so ago and nosedived while training, no damage in that incident . Keeping these flying flat and low is real art in gusty conditions while travelling at 45 knots or over 51 mph.
I flew a catamaran once...it was fun until we “landed”
It's called the top mark, closest to the wind!
🤣🤣🤣🤣🙌🏼🙌🏼
Yeah, and they are very difficult to right without help.
@@JoeLinux2000 and I am sure damn expensive! 😬😬🤦🏻♀️
We would pitch-pole our Hobiecat for fun
& all the power boats would rush to save us.
We were young & fit & two of us could right it.
Next life - - - Sailing.
Once again, you've opened a new area of interest! From this housebound flyer , I thank you most sincerely! Journey mercies!
Thanks for the update, I used to sail and race in my younger years. I miss it a lot.
Really cool analysis Juan. You explained it as well or better than some of the sailing annalists I saw.
As a Boeing guy, I immediately started to get snarky about the boat with "Airbus" on it. But I kept my mouth shut. LOL. Great video!
Always love your analysis and viewpoint. That’s why I’m a Patreon member. I want to see this channel continue!
Did you know that Alexander Graham Bell, was also a poineer in hydrofoil boating? Back in the turn of the 20th century, Bell was living in Nova Scotia, Canada, and after seeing an article on hydrofoils in Scientific American in 1906, Bell began hydrofoil experiments in the summer of 1908. Through his experiments, and a visit to another hydrofoil pioneer, Enrico Forlanini to ride in his hydrofoil in Italia, Bell working with Casey Baldwin eventually created the HD-4 hydrofoil boat. This boat later went on to establish a world marine speed record of 114 km/h (62 kn; 71 mph), which stood for two decades.
nice, thanks for the info. I've also heard that Bell had something to do with the invention of the aileron. there was a professor at Stony Brook U here on Long Island back in the 70s and 80s who put foils on catamarans and even made a foil for windsurfing ca. 1983.
@@asquare9316 Bell was a real smart guy, and his intrestes were wide and broad. Probably one of the greatest inventors of the past 200 years.
BTW. I was around Stony Brook U back in the early 80s, visiting a female freind, and hanging out in the Science Fiction Forum, and going to I-CON.
It's been noted elsewhere that the reason they couldn't sheet out the mainsail is that the running backstay on the port side was still taut. The main was pinned between the two backstays (or whatever they call them nowadays) and there was no way not to stall it deeply. It seems like a procedural error.
edit: Adding that, on fast sailboats the apparent wind differs greatly from the true wind, at least until you suddenly lose most of your forward speed. Then the AOA of the sails suddenly gets dramatically greater and you're in deep stall in less than a second. The apparent wind is of course the sum of boat velocity and true wind; that boat was probably going faster than the true wind so we're talking about a nearly instantaneous AOA increase of 30 or 40 degrees.
I was just watching the races for the first time ever on TV a couple days ago. Thanks for the insight, I knew nothing at all about them, just a few 'guesses'. LOL --gary
Think of the main sail as a rudder. It is much larger than the actual rudder in the water. Trimming the main sail turns the boat as much as the rudder in the water.
They could not release/ease the main sail due to the stuck running back stay. This led to the boat not being able to turn left, downwind. This forced the boat to turn right or “round up”.
The hole in the boat was created by a large battery pack becoming dislodged and then departing the yacht by creating a giant hole! They are going to skip next weekends event. This will give them two weeks to get the boat fixed.
Like you said, that’s flying.
Comparison wise the old 12 meter series to these new boats are like a T28 to the Space Shuttle.
Thanks for sharing your family. I miss sailing. Haven't done it in 40+ years.
Great description of what cause the boat lift and flip over. The speed that these boats go today make the days I was sailing look like a C 47 competing against a Gulf air.....
Juan, Message from a sailor. The reason why the American boat got out of control is because the leeward back stay was not released. If you look closely, early in the manoeuvre , (in fact as the boat starts bearing off after the tack), you will see the trailing edge of the mainsail, instead of falling off a bit, is instead curling up and holding the whole upper sail basically dead amidships. Therefore backstay is not only was stopping the mainsail from being eased but also keeping too much power near the top of the mainsail which overpowered everything.
Just a bit sad really. I used to be a backstay boy years ago when I first started sailing, and woe on me if I didn't release that backstay during a gybe or tack.
Cheers.
Thanks! What was the Captain referring too in his press brief? Or was it guarded 'CYA' talk...? (Regarding the backstays).
@@blancolirio I believe that it was not obviously mentioned. Actually during the incident, when I saw the first clip of it, I could swear that someone in the crew shouted about the backstay just as the boat was going out of control. You understand that crew communications during the racing are broadcast at the same time a commentators.
Cheers
Great video, Juan. Very informative. More so then the American Magic videos! Thanks for sharing!