You WON'T Make It! Now What?
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- Опубликовано: 10 июн 2023
- Is Vx really the BEST Airspeed to climb at if you want to clear an obstacle? In this video, I take a closer look at the zoom climb takeoff; also known as the thrust bump takeoff. In this video, we explore two big energy management principles when it comes to flying. Learn about aviation, and have fun at the same time!
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I personally would love to see the difference between brakes and no brakes on a short field takeoff.
Awesome! I’ll keep that in mind!
I used to train at an airfield with the shortest licensed runway in the UK and my instructor would always have us bring full power in at the same time as we turned from the taxiway to line up for takeoff, in effect making the taxiway part of the available runway length. I presume there's nothing officially wrong with that (I never finished the PPL training, so don't know all the rules), but I'd also be inetersted to see the differences that can make to how much altitude you can gain by a certain point away from the airfield. I imagine the difference would be significant.
@@dan_ yeah, after reading that in the book, I am really interested to try it.
The reason you apply brakes for a short field takeoff is not to shorten the run, but to ensure that your engine is producing full power before you start eating up runway. When you verify, that the engine is developing enough power and you then release the brakes, you are near full power for the short take run.
@@aviatortrucker6285 The run-up should have already happened to ensure full power is being produced. Most bush pilots that need maximum short field performance already have max power as they’re turning onto the center line, whether that’s a 90° or a 180° turn. That way the aircraft already has some momentum. That little bit of momentum makes a difference. So essentially by already moving, it’s like adding another 20-30ft of distance of runway.
I think if you NEED a zoom climb to get out of somewhere it's probably the first hint something is fundenetally not right. In a glider aerotow/self launch we pretty much zoom climb as the norm. But it is more a way to have more options during the takeoff, than a necessity to get over obstacles. If you think you might need a zoom climb to survive maybe you need to think if you need to fly at all.
Maybe. Like I said, I don’t plan on using this every time. It’s only if I get airborne and the plane isn’t performing the way it should
@@FreePilotTraining I enjoyed your enthusiasm and well thought out and well illustrated TECHNICAL explanation. However, if you are operating out of a field where obstacles at the end of the runway is really a factor, the field itself is likely to be short and your time to climb getting shorter all the time as you accelerate in an attempt to climb over them. You need to know AHEAD OF TIME if, barring any malfunction of the aircraft, you WILL clear the obstacle, not be deciding half way there that you might need another technique to get over it. Technical discussion and a few practice runs to "imaginary" obstacles are one thing, and flying out of a truly short field with obstacles ahead is another.....entirely. Opinion is rampant in aviation, however there is one physical reality to deal with in a finite amount of time and that situation does not care what your "opinion" is.
Informative video guys! Thanks for all the detailed content and the often unspoken considerations involved with flying.
Thank you so much! Thanks for watching!
I do takeoffs like this all the time just for fun.
It is a lot of fun to make takeoffs like this
I don't think this is a particularly useful takeoff method for a typical recreational pilot. It's much harder to execute than a simple Vx climb. It's very easy to hurt your chances of outclimbing an obstacle by staying in the ground effect for too long. In case you do fly into your obstacle - you're going faster and have less time to think and lower chances of survival. Your nose is even higher than the Vx pitch angle (which is already uncomfortably high), so you can't see ahead at all and have much higher chances of spatial disorientation from all that clear blue sky in the windshield. Finally, should your engine quit during any phase of the zoom - you're in much worse shape; if it quits during the speed accumulation phase - you're very fast going towards the trees in the ground effect, and if it quits during the zoom - your nose is crazy high, you're close to the trees, and your airspeed will bleed off within fractions of a second.
NOOO. It says "the test pilots lied to you". Im a retired Bush PIlot CFi. Just amazed at the BS some new pilots put on net.
In the Piper Arrow, try holding off on the using the flaps until you are ready to rotate. It takes the energy suck of the flaps out until you need the flap characteristics. Fast and easy to do with the bar. It cuts 100 feet and more in distance to get to altitude. I did the same experiments. Give it a try and maybe post a video on how it went?? Keep the blue side up.
That’s a great idea! I’ve actually read about this technique recently! I’ll have to try it out!
Why I love Pipers more than Cessna. Pop the flaps and jump off the runway but still in ground effect due to low wing. No way with electric flaps and high wings. I also like location of trim tab ;-)
@@joenenninger971 I’m about to make a video comparing the two airplanes
Cool I vote for the Cherokee 235 but l like the Six 300 too.
Stopping and applying full power does reduce takeoff distance. It doesn't do it by a lot unless your engine has a crazy spool time, but there is a reason they do this for things like catapultless carrier takeoffs.
The other good reason for it is it gives you a chance to confirm your engine is producing full power before you're rolling down a short runway.
Let us be honest here. If you are performance limited that you think Vx will not clear obstacles on departure you should sit it out and wait for a more favourable headwind, lower temperatures and ensure the take off surface is dry and not long wet grass.
Agreed, BUT sometimes the winds at 20 feet are different than the winds on the surface. This is where the real problem comes into play
@@FreePilotTraining the wind will veer and increase with height above the uk surface normally unless specific localised features are at play. In normal circumstances the veer and increase is not by a huge factor and if you are in the northern hemisphere and the wind is coming from the left on takeoff you can be pretty much assured the HWC will not change.
If the wind is so dramatic to be a shear problem then you may be at greater risk from localised rotor effects spilling off the local obstacles. Another reason to just not go at that moment and to wait it out.
Cherokees were built in Florida where let’s face it the highest ‘mountain’ is maybe 300-400 feet. Not the ideal aircraft to take mountain flying on any day of the week
I understand you and your colleagues aim with your videos and your good intentions but sometimes the whole story need to be produced or not at all lest the less experienced and skill go off and try things they best not have. All to often in aviation a little knowledge is actually more dangerous as it leads to a false sense of security or a capability that is just not there.
Thanks for the info. These are good concepts to keep in mind, but I guess the reason Vx is the 'go to' speed for clearning obstacles is because it's just a single number to remember. There are a lot more variables with this energy management takeoff, and you might not easily be able to know in advance whether it will get you higher than Vx by a certain point.
That’s exactly right.
Lots of extra level in low ground effect free extra kinetic energy is left on the long runway unused because we think we don't need it. And ten we do and we are already up and have rejected that free energy. Watch the crop duster who takes off max loaded every time. He stays level in six inch ground effect until the end of the runway. I go to the crop field in ground effect unless obstacles force me up.
Rolling on the ground is where you don't know in advance whether you will make it. Think soft field. If the nose gear does not come just off very early, something is wrong. If the can not be brought off well below Vso, something is wrong. Yes, a little dynamic proactive elevator is necessary to level the fuselage when that slow. The extra acceleration advantage make his energy management takeoff safer under any conditions.
@@jimmydulin928 that is such a valid point. Thank you so much for this comment
This method isn’t just for “heavy” low powered aircraft, it’s well suited for low powered aircraft period. We are based at an 1800’ grass strip with 80-100’ tall trees off each end of the runway. This time of year with 90-100 degree temps this kind of energy management take off building as much speed as possible in ground effect is the norm for J-3 cubs. 7AC through 7EC champs, as well as an Ercoupe and a VW powered Sonex on the field.
That’s true! You can use it in a lot of aircraft
I fly a Turbo Arrow III out of KDVT in Phoenix and loved this video. I have always liked to climb out at VX to 500' and than transition to VY. Thanks for these new things to think about and try with my CFI
Thanks Chris! That means a lot!
Always nice to see a familiar face :) hopefully I’ll find you at OSH.
@@JBalloonist I wish I could go. It sounds like a blast.
@@FreePilotTraining it is. Only been once. Flying in this time!
Knowledge is power! lets see all the things!
Very true!
Love this video!
Thank you!
Yes. I'd like to see that in a future video.
The brakes thing.
Ok! I’ll keep that in mind!
Reminds me of the advice for war thunder early jets, never ever just climb at 12 degrees or whatnot off the runway. Reach optimal excess power speed THEN climb.
THIS IS SUCH A GREAT "OUT OF THE BOX" TEACHING! KEEP TEACHING THIS IS SO GOOD! THANKS FOR THE NEW WAYS TO FLY AND STAY ALIVE! GOD BLESS YOU BOTH!
Thank you so much! That means a lot!
This is how I was taught to do a short field takeoff in a Cirrus SR20, rotate, get to Vx (84 knots) in ground effect, then pitch up and after some altitude, flaps off and then go to Vy. I've also heard it makes it easier if you have engine failure, you're still close to the ground. I do this with every takeoff.. if every takeoff is shortfield, I don't need to change anything up depending on which field I'm at.
That’s a good point. Thanks for the comment
That's why my first choice will be the Pipistrel Explorer, a great design with a high glide ratio.
Then I hope to graduate to the new VANS RV15, a great stol design with rough field landing gear.
Wish me luck.
I hope to build an RV-15 as well
On a soft / short TO I retract the flaps in ground effect, huge difference in climb!
Yes, it does make a huge difference
I zoom climb my RV6A quite often and I find I get more altitude closer to the airport which is just money in the bank in case of an engine failure for a potential return to the airport. In most shorter strips I get to about 120 mph in ground affect and do a 2G pull. In longer strips I can be at nearly pattern altitude by the time I get to the end of the runway. In any case I agree with you that the energy management climb can be a nice tool to gain some "cheap" altitude/energy.
That’s exactly right. I’ve had a handful of comments saying that it’s dangerous if you were to lose your engine, but as you just mentioned, it’s actually safer
@@FreePilotTrainingentirely depends on when and where the engine failure occurs. The landing roll in the POH assumes you crossed barrier on speed and configuration. If you stay in ground affect accelerating and the engine failed at that point your choices are going to be trying to land back on at the far end of the runway well above Vref and may well find out those obstacles you planned to zoom over are not frangable at all because let’s face it you were using that technique as the TODA was marginal
Option 2 you would now have to hope you were skilled and practiced enough to zoom climb, bunt to capture VMd as your airspeed decays and hope that was sufficient height above the surface to allow a max rate turnback whilst not pulling into or through the buffet or Stall AoA.
Since turnbask are rarely if ever taught in the civil training world and even in the military world where they are taught and practiced it can be argued that more pilots have instructors have died so sorties practicing turn backs than turn backs from a real engine failure have ever saved.
Option 3 stick to the published POH technique. If you have to end up in the trees far better to do so from above at VRef where the branches are far thinner and will absorbed and dissipate your energy. Most light aircraft are designed that you will survive an impact at touchdown speed if your harnesss is secure. You may not walk away but your survival chance is far greater than hitting the tree trunk square on at high speed because you though you’d zoom out of there but murohu’s law decided otherwise
Huh, this is how I was taught to take off for all takeoffs! It makes short field, soft field, all the same exact procedure each time.
It works! The FAA doesn’t like to see it on the checkride though
Big point to note is that I rarely see anyone properly calculate and adjust rotation speed and Vx for actual gross weight, published Vx in the old GA poh's is always for maximum certified gross weight. Vx will be lower and Vy higher at lower gross weights(and lower density altitudes).
I would be a bit more curious about the results for a closer shorter obstacle, the further and higher the obstacle the more a steady state Vx comes out as the best choice(until it is far enough out to enable a circling climb over airport), but very close in may not allow for gaining the extra speed needed for a zoom climb.
I understand the advantage of raising the gear in ground effect, but say you don't have room for that or you have fixed gear, it seems that gaining speed on the ground while generating no significant lift would be even more efficient than flying in ground effect. (For hard surfaces, not grass.)
I just did the simplistic physics energy calculations and 9 knots of kinetic energy is worth 50-75 feet of gravimetric potential energy (Over the 55-100 knot range of small airplanes). So the only question is how do you maximize the difference between energy added and energy wasted, considering each powerplant-prop combo will have some ideal airspeed and of course the various aerodynamic drags, made more complicated by the changing AoA, ground effect, speed of control inputs. And of course the matter of repeatability and pilot reaction times.
Worth the wait Josh thanks. Just wondering if it's a 150 Cessna when it's got less power? Thank you again.
You’re welcome! Thanks for watching! Yeah, I’m sure this works in a Cessna 150!
4:32 The main reason that I stop and hold the brakes on short field takeoffs is that I want to make sure I am checking all of the engine gauges while not burning up a short runway. When I'm convinced the engine is performing, then I release the brakes for takeoff.
This delays my takeoff roll. So I'm trading time for distance. When I've got a longer runway I'm more comfortable trading some of that runway length for time.
Apart from this, I like this and am going to try it out on the 7000 foot runway at my home airport before trying it on an actual short field.
Ok, I can get behind that. You could check full power at the runup too. I had never heard of this until reading that book. You’ll have to let me know how it goes
@@FreePilotTraining yeah I've never been comfortable going full power without a runway in front of me. I mean, I've done it. But it just makes me nervous. I'd rather do that at the end of the runway to avoid that feeling.
alot of young'ens need to understand this !!
Thanks! I agree!
Fantastic ✈️👍
Thank you!
Looking forward to trying this. Thanks for sharing the technique. Rolling start isn't possible at a few of the short fields I've been to, but would like to see the comparison in a future video.
You’re welcome! Yeah, I’m curious to see the difference too
I learned on short fields so staying in ground effect was somewhat normal for us to do. I wonder if anybody ever thought of giving themselves a few more feet by not staying on the center line but going from corner to corner on the runway, or doing a curve similar to water take-offs?
That’s a very interesting point. I think the reason is that it doesn’t give you that much more runway
This would be a bit dangerous.. what happens if you have an engine failure at that very nose high attitude, right when you pull back?. You will be very slow and you will have a lot of drag.. there are cases where you can't recover
Not necessarily. In reality, it’s safer because you’re carrying additional airspeed. You have energy available. That’s the key
Can you try best glide speed vs pitching down and then fly in almost ground effect to see which one gets you further?
I’ll write that down on my list of videos I’d like to make. Thanks!
The 172M and that I instruct in does not call for a Vx climb on short field takeoffs but calls for a slightly slower speed. Cessna calls it “obstacle clearance speed”. 59kias with flaps up, or 55 with flaps 10. Vx is 64.
That’s super interesting. I’m going to have to take a look at that poh
@@FreePilotTraining I have seen some discussion about similar procedures online. My understanding is that it has something to do with Vx being calculated for steady state flight; while obstacle clearance speed is used while the plane is still accelerating. ACS also has wording to accommodate either airspeed.
Great 👍👍👍
Thank you!
sorry if this is a dumb question, but how are you measuring g forces in the plane / in real time?
We’re using a stratus puck with Foreflight
The problem of simulated DA with low RPM/manifold pressure is... the wing and prop are still taking advantage of the lower altitude air. BUT... it's still a great video for "Food for thought". Thanks for making it.
That’s very true. Thanks for watching
Hey man… glad your doing these.. Also a former AMC guy turned GA fanboy. However, I think you need to be way more scientific.. first, going into any experiment trying to prove a point you already concluded is non-scientific by definition. I think you need better than anecdotal data before telling many young or new pilots to pitch over prior to an obstacle. Also, just watch you can see differences in roll speed during the start of the roll. Hard to take any result from this ‘experiment’ seriously, let alone to recommend a questionable course of action with such a platform.
Thanks! I’m not saying to use this method every time. I’m just saying that it’s smart to consider using this if Vx isn’t going to get you over the trees. You typically don’t figure this out until you’re airborne. I’ve had many takeoffs where I wouldn’t have made it if I just stayed with Vx instead of trading Airspeed for altitude. You can tell in most cases if your going to make it.
What video settings do you use on your Go Pro? Do you use a prop filter? Trying to see why my videos are not as clear. Maybe it’s my settings or my prop filter. Any help would be great!
I like to keep it on 2.7k 60FPS and super view for the cockpit. That camera is an 11. My 9 on the tale is the same but the standard wide view
this would be perfect to debrief with cloud ahoy and see what your runway used per 50' of altitude was.
That is an excellent point!
This is an awesome video. What you didn’t cover was the fact that Vx depends on gross weight and pressure altitude. Usually the published value (particularly older aircraft) is SL and for max gross. Assuming your approximately at SL, below max gross your real Vx is slightly below 85 (about 1% for every 2% below max gross).
It’s possible this difference could account for the 50’ delta you observe.
Further, while I absolutely love how you and Seth are data/measurement oriented, the difference of 50’ could easily be attributed to variations in winds (which you point out) or technique. If you did this 100 times, what would you expect the average difference to be?
In reality, if it’s between these two techniques and the alternative is to auger in, might just opt not to go.
Very true. I’m not trying to prove any points with this video, I’m just pointing out that gaining airspeed is a viable option in many cases. I personally believe it has saved my life a couple times, and I will continue to keep it in my back pocket
@@FreePilotTraining for sure. Also please keep making these videos! This is the first of yours I have seen but you and Seth are awesome.
As a CFI at high DA airport I deal with this kind of thing every day. It is so cool to see people challenging common assumptions!
@@gol3tron will do! Thank you so much
Awesome video Josh and Seth. You are doing great things teaching alternative methods that may save someone's life. I'm headed over to watch Seth's video now. Keep up the excellent work. Safe skies 🇺🇸🛩️
Thanks Kevin! I appreciate that!
@@FreePilotTraining absolutely my pleasure. It's great to know both of you, have the chance to learn from your great tips. 🤘🇺🇸🛩️
@@KevinSmithAviation thank you! Same here!
KCXW is a good airport, I started my training out there.
Yes it is! One of my favorites in this area
Very informative!! “Altitude is money in the bank and speed is money in the pocket. It is good to have a little money in the pocket before worrying about money in the bank!” Now who said that in discussing this exact scenario??
Thank you! I love that comparison!
@@FreePilotTraining Wolfgang Langewiesche in "Stick And Rudder"!!
We have a game called takeoff blackjack. Whoever starts furthest down the runway and doesn't "bust" by hitting the obstacle wins. In MSFS.
😂 that’s the first I’ve heard of this! I do something similar in the C-130 simulator sometimes. The computer says we don’t have enough runway, and I see if we can make it. You’d be surprised at how often we do
Great video! Very informative and interesting. Love it!
Thanks Thad! That means a lot!
Great video, as usual.. Anything with both Josh & Seth you know you’re about to get learned… So you better pay attention…
Thanks man!
Well done video! Thanks for sharing.
Thank you so much!
For comparison, you could have tried a flapless takeoff and climb at 1,3 Vso
I wish I would e tried that
Thank you . Your videos have been informative
You’re welcome!
Some of the climb out examples were in heavy loaded smaller planes at high density on super hot day would this climb out also work in unfair conditions high density super hot day?
Yeah, I do think it could work at high density altitudes on a hot day
I do this almost every take off in my Mooney M20E, with manual gear it is up in 2 seconds while in ground effect. I hit over 3000 ft a min in the initial pull, then get light in the seat to pitch down. I always thought it as fun and a quick altitude gain. I appreciate you putting the theory into it, absolutely makes sense now.
Thank you! Yes, it’s a lot of fun, and it gives you a lot of peace of mind with that extra energy. You were one of my favorite presidents btw…😆
Well it's fine bringing the gear up early like a fighter pilot but if your engine stops, you are belly landing on your prop.
@@a320nick very true. You don’t want to do it every time, but if you need the climb performance, it’s better to belly land than to smack a tree
Having a change of underwear in your headset bag...priceless😊
😂
Great video! And nice to see Seth flying with you - he has some awesome videos as well!
Thank you so much! Yeah, he’s got some great content!
I'm learning to fly in a Pipistrel Alpha trainer. It's Vso is 37. It's Vfe is 70. That's a maximum airspeed during the climb of about 90% above Vso. I'm thinking that's kind of a low safety factor against an accelerated stall for the Alpha. So this maneuver is going to be highly dependent on the airplane?
If you know your airplane, or you are very proficient at stall recovery procedures, the safety buffer may not be needed.
@@FreePilotTraining I suppose rotating and increasing speed to below 70 while at full power and in ground effect, then climbing and looking to pitch for Vx of 58 soon after takeoff may be the best that can be done with the Alpha. I'll have to discuss with other CFIs at airport?
Yeah, that’s a possibility. The other thing to consider is that Vfe is typically FULL Flaps extended so you may be fine. You’d have to look closely at the POH. I also don’t use this technique every time I need to clear an obstacle. I just use it if I think I’m not going to clear something once I’m already airborne
You might need to rename the channel “Tactical Pilot Training”… that was an awesome tactical flying skills lesson. A different way to think about the situation. Great post.
😆 I love it! How about “Tacticool Pilot Training”? Thank you!
@@FreePilotTraining LOL!!! Just need to make sure that "Tacticool" is "Tactifunctional".
I thought this post was fantastic as not many pilots are taught to consider energy state management and how to use it in a practical sense outside of aerobatics. I really appreciated the way you and Seth worked together to bring forward the respective training issues in both of your posts.
You and Seth are the type of pilots that I hope I can tap into if I ever get myse;lf into a position physically to consider getting back into flying and getting recurrent.
Love the channel and what you do.
@@jcmcclain57 thank you so much! Hope to see you around!
An energy management takeoff is how I depart in our PA-22/20-150 when it’s close to gross weight on our 1800’ grass strip with 80-100’ tall trees off each end of the runway. Even with Sullivan extended tips and VGs, with the Pacer’s the short wing, it won’t climb well at its published Vx of 70 mph on a 90 degree F day near gross weight. If you attempt to climb out at Vx in those conditions it will just mush along gaining very little altitude.
In those high DA, near gross weight conditions it won’t climb well at all until it has reached its Vy of 84 mph, and it’s much more effective to just stay in ground effect and build as much speed as possible, starting the pull up at 95-100 mph and using the energy to clear the trees is much more effective.
It works! Thank you so much for the comment
You have flaps? Use them. 10 degrees as least. Do you?
🤔 I wonder if this is why the fighter jets (Tbirds and Angels for example) seem to be only 50 ft off the runway before they pull into the extreme vertical. Granted, there's obviously much more power than Cessna or Piper, but it seems to be necessary to gain the speed and climb at show center. 😊
Yes, I believe it is.
They use a lot of runway to do that. Vx take offs are better to clear obstacles. Former Bush Pilots know that.
oh man, descend, then turn, please. see also AC90-66B/C
How do you measure 1.5 G? Do you have an accelerometer? What if we don't have one, is there a way to guess/measure it? Thanks
So, Foreflight will measure it for you if you have the ADSB on. That’s one way. There may be apps for your phone too
@@FreePilotTraining nice! Didn't know foreflight can do that. Cool
@@MustafaDane it’s such an awesome tool
This is assumption that excess runway is available to build up speed in ground effect before pitching up. If there’s no excess runway available, Vx is still the optimum angle to use
Excellent point. You need excess runway for this technique
When I was getting trained as a helicopter pilot I was trained to stay in ground effect and gather airspeed like this.
Really? In a helicopter? That’s interesting
@@FreePilotTraining helicopters don't get "Effective Translational Lift" until about 25 knots airspeed, where the rotor disc is completely in clean air.
The helo will balloon then.
Then I was trained to stay in ground effect by putting downward pressure on the collective until "best climb", about 60 knots for the little Robinsons I was flying.
@@eknuds that’s interesting. Someday I’m going to get my helicopter ratings
There is also one more consideration to be done here. Losing engine on that very high pitch attitude close to the ground. If you have some space to land straight, that may not be a problem (some serious negative G pitching down though!), but if your only option may be to turn back, it's better to be at Vy (or even above with high spare energy) than high pitch and slowing to increase your chances of success
On the other hand - if you are much faster, your turn radius will also be much higher, so with no engine, you may get pushed further away from the airport while turning (big radius -> decreasing radius, as airspeed decreases)
So all in all, I wonder if while it seems better for clearing the obstacles, is it better for emergencies?
Valid point, although I would say if you are carrying energy like you would for an energy management takeoff, you have way more options during an engine failure
Crop dusters have plenty of energy when they pull up, and I’d say enough for a 180 😬
This was an Awesome Educational video for GA Pilots and I know in the C130 you push a button or pull a handle not sure since I never flew one but that button or level that makes the C130 go into jet mode is good for short field take offs. I bet pull some G's as well.
Thanks Mike! The C-130 I fly doesn’t have the additional thrust, but we don’t really need it when we have 18,000 hp. The gear can be raised by a handle or through the computer (CNIMU). It’s strange. The handle is nothing more than something to make me feel more like a pilot lol
Great Video! Loved it! 👍🏻
Thank you!
The IAS to be flown for VY reduces with increased density altitude as Vy is more a función of TAS
The IAS to be flown for Vx increases with density altitude.
If you are attempting take off at high density altitude airports you need to be aware of those factirs especially as the IAS wil be quite different to the TAS at altitude due to density altitude effects. The indicated Vy must be reduced at altitude.
As a rough rule of thumb you should DECREASE the IAS for Vy by 1% o 2% per thousand feet and INCREASE Vx by 0.5% per thousand feet.
Given he stated he’d use 22HG MAP to simulate I’ll assume he was demonstrating his technique for take-off from an 8000’ density altitude aerodrome.
If he really was concerned about getting the best rate to stay above a SID climb gradient then instead of 100MPH a sped close to 92/93 mph would have been more appropriate.
As an aside. The obstacles to be cleared are often not right off the end of the runway but are the large granite ones a few miles away on the SID or by the VFR lane exit.
Very true. This is why we fly indicated airspeeds instead of true airspeed
@@FreePilotTraining i think you missed the point. In a prolonged climb where it is necessary to maintain Vy you must reduce the IAS by 1.5%-2% per 1000’ altitude increase otherwise you are no longer maintaining Vy
If your ASI has a built in slide rule then you can use that to fly a constant TAS climber VY whilst monitoring IAS. When the IAS reduces to VX and your still maintaining Vy TAS your pretty much at the max altitude your aircraft is realistically going to achieve
My point you never mentioned that the IAS value for Vy must be reduced especially at high density altitudes.
The PAPIs had a sheltered childhood so they’re sensitive 😂
😂 that was a great joke
Dad's gotta dad joke
I'd like to see the results if you retract the gear while in ground effect.
Yeah, we need to try that
@@FreePilotTraining I don't know how much it will help in an Arrow, but in an airplane with fast gear like a Mooney or Banana, should help.
@@bigdaddie40 I could definitely see that. Multi engine OEI climb performance is usually predicated on getting the gear up ASAP
I hope some do not get confused by this video and get hurt. A short field take-off is simply bringing engine to max RPM while "stopped" with brakes on so that the take-off roll is shorter (getting to Vr quicker). Once at Vr, the angle chosen to climb is up to you, but it is DANGEROUS to climb at any angle close to stall, especially at slow speeds. The speed given in the flight manual for Vx is good only at sea level, at max gross weight and with flaps in takeoff position. Vx increases with altitude (about ½ knot per 1,000 feet). So you will need greater speed at higher altitude to achieve a Vx. If you try for greater angles at or below Vx the math quickly changes and if your speed is too low and your angle of climb too high you will stall.
Nope. That’s not true. That’s why we use INDICATED airspeed and not true airspeed when we pitch for Vx. It compensates for thinner air so you are safe when it’s a higher altitude AND when the temperature is hotter.
@@FreePilotTraining Yes it is true, Vx goes up and Vy goes down with height until reaching Vg at the ceiling.
Feel like I’ve seen these two before
Lol, hopefully you’ll see us together again soon!
I prefer the airspeed and altitude method. You can do a lot of stupid stuff at 1000 kph and 10000 meters and live to tell the tale.
I know they exist but where are these airports where you need better than vx to clear an obstacle? Who designed these airports or allowed these obstacles to be put so close to the end of a runway???
I don’t ever plan on using this technique. Typically i use it when Vx isn’t giving me what I thought it should
why not do a zero flaps take off run, accelerate in ground effect and set the flaps just when leaving groznd effect?
I considered that, but I know someone on here would say that the Vx climb is recommended at flaps 25 in the POH, so that’s going to give you the best angle per the manufacturer’s recommendations. I think if I had done flaps up with the energy management takeoff, that’d give us even better performance
The purpose of the basic level in low ground effect takeoff should not be to increase climb performance but to increase acceleration and therefore airspeed. Airspeed, not altitude, is life below an altitude which allows recovery from inadvertent stall after startle delay. There is no need to leave low ground effect before nearing the obstruction. There is no need to overfly the obstruction by lots of clearance giving up maneuverability and/or climb ability, zoom reserve airspeed. There is no need to load the wing much, maybe 1,1 g pull up. Again notice that the crop duster just clears the trees at the end of each spray run. He knows that airspeed, and not altitude, is life down there. High altitude orientation assumes unlimited horizontal as well as vertical space available. This is not the maneuvering flight world we all, not just the crop duster, live in on most every takeoff, pattern, and approach.
Some other low altitude orientation: wind, ground effect, down drainage egress, terrain, zoom reserve airspeed, without zoom reserve airspeed don't pull back on the stick, when pulling back on the stick does not result in climb try pushing just a bit, climb wings level, level wing before pull up, allow the nose to go down as designed in turns or avoid loading the wing, release back pressure in the turn or unload the wing to stay 1 g, density altitude, push yoke in downdraft to get through quicker, pull back in updraft to stay in it longer, ridge lift, thermal lift, most all low powered mountain flight is maneuvering flight.
Thank you so much for your input! Someday, I’d like to get into an Ag plane and learn some of this stuff. I think there’s a lot of stuff that could be shared with the GA world. It seems like there’s a huge divide between knowledge across aviation. It seems like we only learn the things that we THINK we need to know
Is your nosewheel pressure a bit low? Looks flat at 21:09.
Not that I know of, but it might be a little
Thanks for another great video…
Thank you!
Moreover, the practicality of using this method is suspect. By the time you realize you might high-five a tree top, the moment to use this idea has passed. You’d have to use this from brick one of the runway or at least the point of rotation. Conversely, you probably wouldn’t or shouldn’t use this theory from the start as the plan, because if you think you need this questionable theory to make another 50 feet , you probably need to pick another runway or lighten up the plane to achieve performance with a margin for error. Again thanks for doing the video but I think this one needs an opposing view.
You typically know as soon as you get airborne and she doesn’t want to climb.
Suspect?
Nevermind the fact that some of us been using this technique for over 40 yrs..
Great video. It’s something to practice and have in the back pocket!
Thank you! Yes it is!
I call that the Fat Albert takeoff!
Lol, that’s actually exactly what he does!
@@FreePilotTraining I used to do that regularly in my 150 at C83. It’s pretty fun!!
I heard you don’t need a radio to fly in uncontrolled airspace. If that’s true, how do pilots make sure they are avoiding traffic in uncontrolled airspace if not everyone has a radio?
You don’t. It’s not too smart though. You just have to be really vigilant without radios
@@FreePilotTraining I see, it seems like pilots trust each other in the air a lot more than drivers on the road, lol (probably for good reason). By the way, I do appreciate you reading all your comments and responding to them so quickly whether to a novice like me or a fellow pilot. You earned my subscription, keep it up 👍🏻
@@rqlk yes, it seems like we do. Thank you so much! I’ll see you around
Sounds like the perfect recipe for a stall spin on takeoff for newbie pilots. Nevertheless, Assuming one uses this technique as promoted (without entering a stall) , the pilot is trading off precious distance that could be used for climbing, in exchange for more speed and a very short-lived faster climb rate. I’m dubious whether this would produce any net benefit in altitude. There is a reason Vx is calculated for every airplane. A pilot should be hesitant to substitute his own seat-of-the-pants feelings about aerodynamics (i.e. zoom climbing) for long-established proven aerodynamic principles.
I appreciate the comment. You should really read the comments on this video. There are quite a few pilots who use this technique. This is especially common with crop dusters
On a runway half the length the height distance is negligible. If that is what someone is relying on to clear an obstacle then they should think about lightening the aircraft.
No, this is simply something to keep in your back pocket if you’ve already made the decision to go and your airplane isn’t performing the way it should
T-LAR That looks about right or is it something else.
Yep. Is there another meaning? Lol
Lets see that on a real 50 feet obstacle 1,800 feet long runway at full gross and 60 F temp. at sea level (normal conditions).
I bet we’d be fine
@@FreePilotTraining Your answer tells me you really do not understand the situation. You have a tremendous influence on new and aspiring pilots. Please consider this when posting. Commercial Pilot, fixed wing, rotorcraft helicopter, CFI, 49 years flying.
@@northwestrctv5584 YOU ARE RIGHT. THIS GUY DONT WANT TO POST A VIDEO PROVING HIS THEORY. iM A Fprmer Bush Pilot CFI in South America and USA 4 states. Talking is CHEAP, Doing is king.
Not related to the content, but you may want to normalize your audio between the voice over segments and the live audio. Some are hard to hear when you turn down the volume for the live segments.
I really appreciate the comment. The crazy part is that I’ve done that and intentionally turned the volume way down on those parts
Seems like to me a chandelle without the turn.
That’s basically what it is! Great point!
Good Technique!
Thanks!
Interesting thank you for your video. It will be nice to combine a G meter with angle of attack in one instrument to avoid accelerated stall. That is my 2 cents on this experiment.
Yeah, it’d be nice to have a G Meter
Great video. You and Seth work great together as teachers. You would have been even higher than 640 on the energy management takeoff because you lost out on a higher airspeed by having to come back down a notch to stay in ground effect. If you had stayed in ground effect all the way, you would have been some 10 MPH faster before the zoom climb I bet.
I also agree with the earlier poster that a rolling take-off from taxiway is better than full stop and then full power. Momentum carried onto the runway means more energy available to accelerate aircraft to a higher speed more quickly because initial inertia is less than maximum. In this case, the taxiway should be at the end of the threshold. With a wide runway, a turning around on runway and continuing rolling take off without stopping would help as well.
Thank you so much! Yes, I think I would have been even higher if I would’ve stayed down. Maybe even higher if I would have kept flaps up to reduce drag. I just went with the manufacturer recommendations, but I have my doubts about their procedures
KCXW!!
Great airport!
@@FreePilotTraining oh yeah a guard UH-60 pilot out at Robinson, fly the planes out of NLR Air frequently! Nice to see 1517X on RUclips!
@@dpip96 that’s cool! Yeah, she’s an awesome plane
When will the next PPL lesson video come bro ? Also can you do a pre flight video for the check ride like how to do a proper pre flight ? C172
I’m working on it right now. Hopefully I can finish it up in the next couple weeks. I’ll see what I can do about a good preflight
@@FreePilotTraining thanks man ! There’s barely any proper videos for preflight online !! I’m pretty sure it would benefit a lot of people and specially for students when the Examiner asks what are you looking for and the student goes “ 🥲 RIP “
@@channelclosed4037 thank you so much for that info. I assumed there were a ton. I will definitely make one
@@FreePilotTraining thank you bro !! You the best can’t wait for this one !! You are my fav instructor on RUclips
@@channelclosed4037 thank you so much! That means a lot
There is no way (at least for your standard 172) bringing the airplane to a full stop helps shorten the takeoff roll. It only takes like 2 seconds to spin up the prop; you'd definitely be getting more energy from the airplane already moving during a running start. I don't understand why FAA is teaching it this way, do they expect us to do short field takeoffs in a jet or something?.. I still do it every time for normal take off simply because it gives one a great opportunity to check static RPM and take one last look at engine instruments while you're stationary and can't run off the runway.
I completely agree with this. That’s one of the reasons I want to test this. Sparky Imeson claims that running up while static can damage the prop and stab too
Full stop allows you to use the full length of the runway. 99% of pilots will lose at least 40' if they just start rolling, especially the pilots that dance a bit around the center line at the beginning of the role.
The airline industry refers to this procedure as an “improved performance” takeoff.
Ah, I was looking all over for the best name for this. Thanks!
@@FreePilotTraining, Airline industry gave it up because, like voodoo, it’s speculative. And, it does not work. What does work is using alternative center of gravity.
As a CFI, you should know better than to prescribe voodoo to the masses. This video of misinformation runs the fine line of professional misconduct.
Totally agree with you guys!!
It seems that the reason they saved the day on the video you showed is because commanded or not the aircraft is pitched nose below horizon at brief times.
Now! Here is my approach to the matter: climbing out straight at Vx will never give you the best chance to clear an obstacle and this is why.
Remember that the horizontal stabilizer exerts a negative lifting force which adds up to the total weight of your aircraft so, by retarding the time at which your aircraft has to lift all that weight you are gaining energy to do so. Also avoiding all the drag involved on the event.
Remember also that flight manuals and procedures are written by engineers and latter corrected by lawyers.
Not an extremely difficult maneuver but not recommended for the eventual flyer. If you don’t understand your aircraft enough you shouldn’t be trying this maneuvers and you should stick to your lawyer dictated procedures so if you crash they can sue the aircraft, engine, tire and even spark plug manufacturers.
I write this with full understanding of this maneuver after flying for more than 25 years for the federal police in mexico on non approved runways hot high and heavy.
Yes, knowing your airplane is the key
wow that nose wheel looks low... maybe it woudld be better with that thing inflated lol.
That’s weird. I didn’t notice that before. Lol
Great theoretical topic, but it seems like you're splitting too many hairs on this one. Sure, your initial climb after the pull will be steeper, but you're also making up for being lower AGL farther down the runway. Another nuance that less experienced pilots may not appreciate is the difference between aircraft deck angle, AoA, and actual flight path. You guys were kicking around some ft/NM vs ft/min values, which is the right way to go for planning; one could argue that you could sketch out the whole scenario before ever getting in the aircraft to see if the numbers make sense. An example is, "Can I reach 60' AGL by DER on a 2200' strip?". Connecting the dots from the anticipated liftoff point to the obstacle creates a triangle. The pitch of the hypotenuse becomes the ft/NM performance goal for the calculations (3 degrees is roughly 300'/NM, and so on, and it must be done in groundspeed, not IAS); this assumes your audience is proficient in making the conversion to ft/min or in using the performance cues provided by a glass panel. And, as always, add a buffer for error. Some old timers would also go so far as to pace off a no-later-than liftoff point and/or a no-later-than reject point (whichever is more restrictive) and mark it to verify performance and back up an abort decision. Again, great topic, but, the greatest lesson here is that, if the performance is this tight, then shouldn't you delay until conditions improve?
Yes, you should delay until conditions improve, but sometimes you don’t find out until after you’re airborne that things aren’t what you calculated. That’s the whole point in this video
@@FreePilotTraining Let's agree to disagree.
Old CFI stable: 3 most useless things in flying 1) runway behind you 2) altitude above you 3) student pilot. Don't rag on me I was AF Flight Instructor for 5 years.
😆 I’ve only ever heard the first two. Lol
Thank you my Brothers for the Lessons.
You’re welcome!
Activate like 6 cameras and jump. That's what the pros do for youtube lol.
Lol, it’s time consuming enough with 3 cameras. Those guys can afford an editor
I did this type of takeoff regularly flying a C150 out of airports with field elevations over 5000ft. I took off, stayed in ground effect to gain airspeed, then pitched for Vx. I prefer to pitch to Vx and no more. The excess airspeed will automatically bleed off until it reaches Vx speed (this requires knowing your normal pitch attitude for Vx). And by not over rotating, you don't have to worry about getting slower than Vx or stalling at any point, or misjudging the pitch down timing. It might cost a little performance, not sure, but in the C150 the speed bleeds off so fast once you pitch to Vx that I doubt it made a noticeable difference.
Absolutly fantastic. Question, Do you think your short field training with the C130 helped you develop this superior knowledge/skills?, cause I have watched dozens of videos that explain that but no one has simplified it like the way you did. I am a firm believer that the deeper you understand a subject, the better you become at simplifying it and the more your teaches it, the better it sticks. Keep the good work.
Thank you so much! That’s a great question. I definitely think it has made me more well rounded, but I have done a tremendous amount of research when it comes to the things I don’t know and that always yields some interesting knowledge.
tear drops are STUPID! you should make a video on how stupid it is and how it should be removed from the literature. If your crossing midfield JUST ENTER the downwind!
Lol, I don’t like them either but when the pattern is busy, that’s what you should do to get the proper sequence
If there was a 50 foot obstacle like a tree at the end of the runway, I probably would just steer right or left of it.
Definitely. It’s usually not one tree that’s the problem, it’s their friends
@@FreePilotTraining what about two trees 😂
@@susansticazsky9787 a larger turn?
@@FreePilotTraining I remember when I was stationed at Ellsworth Air Force Base they had to move the town practically of box elder because all the buildings were in the safe zone flight path of the B1B. You would think the FAA would limit the amount of obstructions in a short field area for a legal certified airfield.
usually there's more than just 1 tree, also turning affects your climb performance - (sometimes) it may not be as easy as turn