Kudos to those mathematicians who figured out the precise location of the fractured metal pieces in both the scenarios. And let's take a moment to appreciate this flight crew for their commendable action in bringing the airplane safely to the ground.
I'm a math guy and the technique they use to find stuff is really cool. They basically treat it like a scientific profess where they incorporate new information as it's acquired to improve their probabilistic model and narrow down the search area as they go. It's relatively simple mathematically but the fact that it works so often blows my mind.
WOW. Just WOW. You are definitely a storyteller. Words can not describe the accuracy of the mathematicians. I am really happy with the way they handled everything. Absolutely blown away by this story.
@@suresh1957 Indeed. "Pay no attention to what the critics say. A statue has never been erected in honor of a critic." -- Finnish composer Jean Sibelius
Indeed a very good presentation. Just a minor correction: The dent hydraulic lines have nothing to do with the controllability of the aircraft. The primary flight controls of the ATR are manual. The hydraulic lines are for the landing gear, the the landing gear extension system has a manual backup.
@@090giver090 oh, sorry I’m not trying to make my own point! I’m just saying what the other poster said in shorter terms bc Simplex said “English please”
Just wanted to say what a great job you do on these investigations. Your knowledge and emotional involvement shine through while you avoid the classic pitfalls of the videos becoming dry or overly-dramatic. Well done and thanks for the great content!
Metal fatigue on my Cessna 172 prop caused an inflight loss of a tip. The fracture was probably the result of a small stone ding about 3 inches inboard of the tip when the prior owner hit a snow bank under power. It felt like the engine was about to rip off the mounts. Quickly shut down and dead sticked it into a small airport that happened to be close by. Very “exciting” experience. Metal fatigue is a major issue in all machinery. Keep vigilant!
hopefully you got all the gears or whatever other internal components thoroughly checked too... nasty issues from such overstress events can tend to crop up hundreds of hours later.
I bet that beer tasted pretty good after you got her down safely. Good call replacing the engine. Wouldn't want to have it seize and need to do another dead-stick landing. Better safe than sorry eh, especially with aircraft.
I think we should take the time to thank the hard-working engineers and guys on the assembly line who built a plane so tough that it could survive a propeller blade slicing into it at 19,000 feet. A lot of guys and their factory really took the time to do the job right, and thanks to that, nobody had to die in this freak accident This is why the guys who put stuff together like this need to be well trained, healthy, and well compensated. Part somebody messes up because they are tired or sick or hungry could turn something like this into a mass casualty event.
@@higueraft571 Yes, SpaceX has a culture of actively seeking out potential problems and fixing them. Any employee can go straight to the COO or CEO if they think their problem isn't being addressed. They also have a " no ahole" clause written into their employee contract. I think that would be a great addition to any company's employment contract. Yes I am a fan-boy don't sue me. :)
This video is a prime example of all the things you do right. Length, style, insight! The information on what improvements were made based on the incident and investigation really sets you above the pack.
Statisticians: "There's a 30% probability of it being within a mile of your present location, a 15% probability of it being in your pants pocket in the dirty laundry basket, and a 65% probability of it being between the couch cushions where you took a nap yesterday afternoon" ;*p
I have this little card called a tile, it's the size of a credit card, if you lose your wallet you can use your phone to make an alarm go off. It's pretty cool. Also, if you lose your phone theres a button on the tile you press and your phones sounds off even if its turned off.
There is actually a term that I learned a few days ago* for a chain of events that leads to a disaster: The Swiss Cheese Model of Accident Causation :) Whew, that's a long one. *From another comment made by a viewer on a different vid by Mini Air Crash Investigations. :) It is a theory that was discovered in the 1990s. It states that for a chain of events, where some go minor problems unnoticed, and lead to higher probabilities for problems to arise down the line (series of events lead to accident).
@@kdrapertrucker _"Don't fly on them in cold weather, their driving systems suck."_ Did you mean their *deicing* systems? If so, that's true. Their deicing systems are notoriously -- fatally -- ineffective.
I love that your videos appear on Wednesday mornings, my time, at about 5 hours. This was really interesting and the fact that investigators were able to find that lost propeller is just another example of the unreasonable effectiveness of mathematics (math rules!). Mini Aircraft Investigation and Mentour are the only two channels about air crashes that I watch. BTW, one of your viewers turned me on to Mentour. These channels compliment each other in some sense. Both of you are gifted investigators and commentators, each with your own unique talents. Mentour satisfies my retired engineer's craving for technical details. You have the gift of breaking down complex scenarios in such a way that we non-pilot mortals can understand. Forgive me, if I'm being cheeky in saying this, but I'd love to watch a collaboration between the two of you discussing some major event.
May I give you a tip for another channel that, judging by your comment I think may be "up your street"? Have a look at the "Blancolirio" channel presented by Juan Browne. Factual aviation stories, well presented by a well qualified pilot. It's a great channel to learn from, too. All the best, safe travels 👍 ✈
And one more channel to check out if you wish: 74 Gear. From his 'about' page: "74 Gear / Pilot Kelsey, Boeing 747 Airline Pilot , All about aviation from passengers to pilots." And, yes, I, too, follow MAI and Mentour.
Fantastic! Road salt is prohibited from use at airports for this reason, and chlorinated chemicals in general are generally unwelcome. Even A-B-C fire extinguishers are prohibited due to corrosive effects on aluminum. Only B-C fire extinguishers are permitted in the AOA. I love videos like this because I teach many people how to operate safely in an airfield environment and references like this help me explain how small things can have an effect or why rules that may seem over-burdensome exist. It really helps when there is a rule that needs to be complied with if I have a concrete incident to point to that reinforces the importance.
I gather there are also severe restrictions on shipping gallium by air, because if it melted (I believe it melts at about 30 °C, so sitting on the tarmac on a hot day could do the job) and leaked from its container, it could alloy with the aluminum of the fuselage skin and create a weak spot.
Great presentation. While flying in helicopters in Hawaii a soldier in my unit had is M16 rifle fall out. A very serious issue for a fully automatic rifle that must be accounted for and secured. About 1500 soldiers were walking all over a very difficult part of the North Shore. One of the Lieutenants who was a math major got all the parameters and told us where to look in a 100 meter area. And yup, that’s where we found it. Gotta love math in a practical application. 👍
The subject of metal fatigue was the subject of 1948 book by Nevil Shute called No Highway In The Sky later made into a film starring Jimmy Stewart as an aeronautical engineer convinced that metal fatigue was going to cause catastrophic failure of an airframe during flight. Its an old relic of a movie that every aviation buff should see. Note that the late Mr. Stewart was a WW2 B17 pilot with 20 missions to his credit. He was eventually promoted to Lt General of the USAF Reserve. I hope all the channels viewers are wearing their red poppy's in recognition of Armistice/Remembrance day on Nov 11. Good video, well done!
Who says you don’t need to know math? The mathematicians in this video are heroes. If the missing parts of the propellers weren’t found other propellers in service on other planes could have failed and led to crashes.
Brilliant post. I didn't know about this one. And I really like the appreciation for mathematicians. I have a brother who is a mathematician, a nephew who has a degree in math, my son has a degree in math, as do I. I watched an MIT Open Course (?) earlier today on math. I couldn't quite follow it all although it was undergrad!
There was another accident involving prop disintegration on a similar aircraft that related to actual prop examination techniques. That accident had fatalities sadly. I don't have the link handy. You may be happy about this.
One of the few channels that make videos about incidents. So many videos with tragic flights were everyone died, good job covering these 99% worst-case scenarios. Great to know this histories.
ATR has mechanical controls and hydraulics are used for landing gear(can be extended manually), flaps, braking, etc. It would have been a tough day nevertheless if the hydraulics were lost. Well done to the crew for safely landing the plane.
As a a French Canadian, from Abitibi, Val D'Or is just pronounced Val dor. And Dorval is pronounced exactly the same but backward. Which is kinda funny. valdorvaldorval.
@@amazing7633 Yes. Although Little Abitibi River is in North Ontario-i-o. I live in the Abitibi region of Quebec. Near the Abitibi Lake which flows into the Abitibi River.
4:08 Just short information about the ATR controlles. The ATR is a cable controlled plane. The hydraulic is just used to work the flaps and landing gear.
Deformation mechanics (especially fatigue crack propagation) were a specialty of mine back in the mid-eighties as a materials engineer. It's amazing how cracks propagating from material defects (especially pitting and inclusions) can cause failures at levels so far below actual strength limits simply due to cyclical fatigue. This was not fully appreciated until after the crash of the Dehavilland Comets in the early fifties.
Excellent narration as always! One minor quibble: "Quebec" ought to be pronounced either as "kuh-BECK", "kay-BECK" (which is the French-Canadian pronunciation), or "kwa-BECK", rather than "kyu". Also, as @MarcDennis and @dmav522 noted, "Val d'Or" (literally Golden Valley) is pronounced like "Val Door".
My parents are mathematicians but I screw math up because I sometimes switch the order of the individual digits in a number. In any case, I have a hint for being able to always know where your pocket things (like your wallet) are. I always put all of mine into a plastic container and put it near the door. When I leave, I simply put all the stuff in the container into my pockets and can rest assured that I'm not forgetting anything. Then, when I come home, I take those pocket things out of my pockets again and put them back into the plastic container. There are lots of things that can be done through checklists or by having everything that has to be done in a short amount of time together. Might as well save the real thinking for problems you hadn't anticipated because there's no way to be alive without having quite a number of those kinds of problems.
I still don't know why they don't put cameras on planes that let the pilots see the engines. If SpaceX can live stream during launches, cameras can work on a plane.
It’s quite easy Cost and workload for pilots. Cameras means more displays, more displays mean extra training. Extra training is expensive. Taking care of displays and cameras is expensive. Buying them in the first place is expensive
On top of what the other commenters said, the number of crashes that could have been avoided by having cameras all over is negligible, and you wouldn’t be able to view every part of the plane anyway. It’s just not worth doing.
@@Sashazur It might be worth doing, since planes already cost $10M-$100M. :) Even if a camera system costs $10,000, and 5 hours of training, that is nothing in comparison to the cost of the aircraft. Plus also, onboard AI could monitor the camera data on such a future aircraft design. That is just my opinion. Anyways, merry Christmas/happy holidays. 🎄🕎
Loved this episode like all of them! Of course we got another example of pilot skill and coolness under pressure - but this time the emphasis was a bit more on some science. Not just the clever maths employed in locating the propeller, but the metallurgy, physics and chemistry involved in designing, testing, manufacturing, monitoring and developing all parts of an aircraft but particularly really critical parts like prop blades. Mind you - and this is the thing with aircraft and aviation which totally differentiates it from all other forms of transport(excepting Space) - basically EVERYTHING is critical!!!!
Mind I make a suggestion? I recommend looking into Avianca flight 011, it’s an interesting crash which resulted in a large loss of life but yet is never really mentioned. Also interesting circumstances surrounding it. Even a book was made about it a few years back too
Got a future story for you. ZZ333. RAF Voyager KC2 that suddenly pitched down sharply. For once not a computer failure and actually it was the FBW that saved the plane
I love the detail and the focus here. We owe a debt to Neville Shute and his story No Highway in the Sky (made into a film) for raising the awareness of the public about metal fatigue back in the 1950s. There was a lot of scepticism at first. Famously the breakup of early Comet aircraft confirmed it.
Whew! You got me with the title of the video. Yay for the mathematicians (truly amazing accomplishment) and thank you for NOT walking us through all the equations. 😅😅
"Looking for a needle in a haystack, when you don't know where the haystack is" - this one had me chuckle, I like your humour... (luckily no one got hurt here, so there's room for it)
I worked in the aluminum industry a while ago. One time there had been rumors, that we would get contracts by the aero industry. As someone with privat pilot background and somewhat being an aircraft nerd, I was excited and shocked at the same time. Excited for obvious reasons, but shocked because I knew about the high safety responibilitys and my doubts about if my direct superiours would know aswell. Anyways, the contract never came, so there is that.
This video shows the importance of regular non destructive testings and inspections not only in aviation but in all fields of engineering and construction.
At the time of the accident, there was no non destructive testing available to find the corrosion. This includes visual inspection, as the lead wool that was used for the individual blade balance did not need to be removed, it was also not encouraged to be completely remove due to possible mechanical damage.
An incredible level of detail. And thank you for praising mathematicians. I only have a bachelor's degree in mathematics and it made my brain hurt. Mini Air Crash Investigation, thank you for your efforts. May you and yours stay well and prosper.
Interesting regarding the cork. Cork is no longer washed or steamed with chlorinated water as it produces TCA - the compound that causes the 'corked taint in wine. However for industrial use production of the cork is very different.
Most fatigue cracks occur on exterior surfaces where stresses are usually the greatest. For example, the outside of a shaft in torsion experiences the greatest shear stress and can be detected using visual or fluorescent dye penetration inspections. Corrosion as in this case initiates cracks in nontypical places. Slag inclusions inside components also create fatigue cracking not visible in the surface, need more sophisticated detection methods (x-rays?) and have caused unexpected failures in turbine engine disks.
And yet a yet later on Atlantic Southeast Airlines Flight 529, a nearly identical blade corrosion issue happened with much more serious consequences. :(
Correct, but the blade that failed on the ASA flight had issues passing the original Ultra Sound inspection from the first two failures. It is possible that some of the corrosion pitting on the blade caused it to fail about 17 months after this in August 1995.
This accident is eerily familiar. The USMC C-130 tanker that crashed in Mississippi (?) recently was brought down by a thrown #2 propeller (metal corrosion) that went thorough the fuselage, consequently the skin started coming off, then a gearbox failed on #3 due to vibration and prop #3 came off causing the cockpit area to break off the fuselage.
I wouldn’t argue with the findings - when you speak of low level chemistry reactions, could acid content in the air moisture content contribute at? The pit like indentation also occurs on the back of propellers in marine vessels, it’s called cavitation. Just compare the issue of compression and vacuum front and rear of prop, then compare density of water and air - add in the relative speed of marine props and aeroplane props or screws as they were once called.
Interesting way to balance things. Typically with balancing, they will remove material, usually by drilling/milling or with a laser, from points where the balancing machine determines. But I suppose it was designed this way for a reason.
Any material removed from the prop blade will change its shape thus aerodynamic characteristics (and stiffness, vibration resonances and so on). So other means had to be developed. Dynamic balance is also dependent on the mass distribution throughout the blade (where the material is removed). Consider balancing a car wheel. Mass is added, not subtracted.
I was eating pea-soup, watching this story. The spoon were held in position in front of my mouth, mustache and beard (poor spoon), for a rather long time, as you told about the ordeal, from the bang, down to :..... And thankfully it did (held together until they landed). I did not eat the soup in that spoon, before that plane touched down! I'm deeply impressed by your storytelling, the way you use your voice, it's just an awesome channel, where you present us for the fruits of your investigations! Love it :) And what's the story about the 15 "nope" folks????
A piece of the propeller penetrating the fuselage is another night-mare scenario. But much more srvivable than having a wing torn off. It really helps me to feel better about flying because I know the extent to which they investigate these crashes. "There is no such thing as 100% reliability.". Truth! But, thanks to investigations into incidents, we keep moving the march of 9's further every year.
I always liked the ATR, I guess it epitomizes the regional aircraft to me. But til now, I didn’t realize how small the wing is relative to the fuselage. This is the 2nd incident I’ve learned about where the cork in the propeller was the nugget.
Well from steel or iron water pipes it is known, that wood under lied to equalize the pipeline during installation leads to local pit corrosion in the steel or iron tube, due to organic acids formed when covered with earth and humidity, this can destroy iron tubes with 1 cm wall strength within 20 years.But water storages from the Bronze Age build entirely from wood lasted nearly 2800 years and where removed finally due to mud accumulation. So wood itself properly cut in winter, so as to reduce its sugar content, and probably treated with its own oil and resin can last very very long! Unfortunately when they removed it and put it in the museum of San Murezzan, St. Moritz Switzerland, they painted it with black coal tar and cut a big hole.
This incident reminds of a similar one with a Embraer I think in the US. Not sure anymore. But can remember the same cork and chlorine stuff. It’s not an ATR fail, it’s Hamilton Standard, the prop manufacturer.
4:05 There is a big missinformation. The ATR is a cable plane, no hydralics are used for the alerons, elevator or rudder. The only thing that would have not worked, would be the flaps and the hydraulics for the landinggear but this has a backup function.
I like these lesser known ones where the ending could have been horrible but the pilots (and luck) managed to save the day and everyone was okay. Maybe less dramatic than the big crashes but cool to see how even if something goes horribly wrong, a lot of the time things work out. I’m Canadian and had never heard of this one.
You give the impression that the number two engine was kept running which seems impossible given the blade imbalance. Indeed a fascinating story digging back to the root cause.
After the portion of the blade broke off, the rest of the propeller imbalance caused it to break off the front of the gear box and leave the aircraft. So there was no thrust from the right/#2 engine.
8:53 Turbo prop animation on left side of video is playing behind the plane wing, meaning it looks weird. I don't know what animation software this is but that would be a rather odd glitch to fly around with in real life! 😅😊👍
There's also the American Airlines Flight 191 incident where metal fatigue (stress crack) caused an entire engine to rip away during takeoff. Although that was a result of airlines caring more about savings vs. safety rather than a chemical reaction.
Stuff the number crunchers, the pilots were the heroes here. Wise decision not to stress the hull any further than needed, but testament to a good design.
Interesting video. The sleuth work required to figure out where the corrosion came from is impressive. For the record, there's no such place as Val-Dior. The place is called Val-Dor
Kudos to those mathematicians who figured out the precise location of the fractured metal pieces in both the scenarios. And let's take a moment to appreciate this flight crew for their commendable action in bringing the airplane safely to the ground.
I'm a math guy and the technique they use to find stuff is really cool. They basically treat it like a scientific profess where they incorporate new information as it's acquired to improve their probabilistic model and narrow down the search area as they go. It's relatively simple mathematically but the fact that it works so often blows my mind.
WOW. Just WOW. You are definitely a storyteller. Words can not describe the accuracy of the mathematicians. I am really happy with the way they handled everything. Absolutely blown away by this story.
Bruh he can't even spell Canadian correctly...
@@jaggerdfletcher1618He made a typo. Is that so much trouble for you?
@@dimitarivanov3817 Very well said Sir. Easier to find faults than to create something like this wonderful analysis
@@suresh1957 Indeed. "Pay no attention to what the critics say. A statue has never been erected in honor of a critic." -- Finnish composer Jean Sibelius
Dude the airline is literally called inter canadien That’s how they chose to spell their name what can I do? 🤷♂️
Indeed a very good presentation. Just a minor correction: The dent hydraulic lines have nothing to do with the controllability of the aircraft. The primary flight controls of the ATR are manual. The hydraulic lines are for the landing gear, the the landing gear extension system has a manual backup.
Good catch! My bad!
English please
@@Jfjcjfjfjf even if the hydraulic line were cut by the propellor, the pilots would still be able to control the plane.
@@tabittheha But belly landing the plane with compromised structure would not be a pleasant experience...
@@090giver090 oh, sorry I’m not trying to make my own point! I’m just saying what the other poster said in shorter terms bc Simplex said “English please”
Just wanted to say what a great job you do on these investigations. Your knowledge and emotional involvement shine through while you avoid the classic pitfalls of the videos becoming dry or overly-dramatic.
Well done and thanks for the great content!
Thank you!
Metal fatigue on my Cessna 172 prop caused an inflight loss of a tip. The fracture was probably the result of a small stone ding about 3 inches inboard of the tip when the prior owner hit a snow bank under power. It felt like the engine was about to rip off the mounts. Quickly shut down and dead sticked it into a small airport that happened to be close by. Very “exciting” experience.
Metal fatigue is a major issue in all machinery. Keep vigilant!
Yikes! Glad it wasn't more serious.
hopefully you got all the gears or whatever other internal components thoroughly checked too... nasty issues from such overstress events can tend to crop up hundreds of hours later.
Nothing like the threat of death to make us sit up straight and take notice!
I'm glad you're okay too. 👍
@@stanislavkostarnov2157 True. Did a tear down and some inspection but ended up getting a new engine. LYC-360
I bet that beer tasted pretty good after you got her down safely.
Good call replacing the engine. Wouldn't want to have it seize and need to do another dead-stick landing. Better safe than sorry eh, especially with aircraft.
"Where's the propeller now?"
"Canada"
Mathematician: "I can figure this out"
I think we should take the time to thank the hard-working engineers and guys on the assembly line who built a plane so tough that it could survive a propeller blade slicing into it at 19,000 feet. A lot of guys and their factory really took the time to do the job right, and thanks to that, nobody had to die in this freak accident
This is why the guys who put stuff together like this need to be well trained, healthy, and well compensated. Part somebody messes up because they are tired or sick or hungry could turn something like this into a mass casualty event.
So true. Great point
Given all the quality control issues that Boeing has been having lately, they'd do well to heed your excellent and timeless advice! 🤔
@@daviddunsmore103 Naaahhh, profits are more important to the suits. Cover up any shortcomings.
@@daviddunsmore103 Honestly, i'd ask SpaceX to build your plane at this point...
@@higueraft571 Yes, SpaceX has a culture of actively seeking out potential problems and fixing them. Any employee can go straight to the COO or CEO if they think their problem isn't being addressed. They also have a " no ahole" clause written into their employee contract. I think that would be a great addition to any company's employment contract. Yes I am a fan-boy don't sue me. :)
This video is a prime example of all the things you do right. Length, style, insight! The information on what improvements were made based on the incident and investigation really sets you above the pack.
Great detective story on so many levels. really enjoy your sense of humor, too!
The premium quality of your presentations is unequalled anywhere. Fine work!
Mini Air Crash: "Guys, I can't find my wallet. Can you help?"
Mathematicians: "We're mathematicians...not miracle workers."
Mathematicians: at what location, altitude and direction did you throw your wallet?
Statisticians:
"There's a 30% probability of it being within a mile of your present location, a 15% probability of it being in your pants pocket in the dirty laundry basket, and a 65% probability of it being between the couch cushions where you took a nap yesterday afternoon" ;*p
@@stevengill1736 "73.6% of all statistics are made up."
@@josephmassaro LOL
I have this little card called a tile, it's the size of a credit card, if you lose your wallet you can use your phone to make an alarm go off. It's pretty cool. Also, if you lose your phone theres a button on the tile you press and your phones sounds off even if its turned off.
What an insane chain of events!! Great storytelling, you summed up everything very well and kept it quite interesting.
There is actually a term that I learned a few days ago* for a chain of events that leads to a disaster: The Swiss Cheese Model of Accident Causation :) Whew, that's a long one.
*From another comment made by a viewer on a different vid by Mini Air Crash Investigations. :) It is a theory that was discovered in the 1990s. It states that for a chain of events, where some go minor problems unnoticed, and lead to higher probabilities for problems to arise down the line (series of events lead to accident).
Finding that prop blade is like finding a needle in a haystack that's in a massive field full of haystacks. Amazing stuff, great video once again!
I love flying in those ATR72's, but I always make a point of NOT sitting in the row in-line with the props or the one in front 😉
Don't fly on them in cold weather, their driving systems suck.
And don't order wine during the flight.
The prop arc is one thing . Sitting two seats back and being in line with the compressor wheels is just as if not more dangerous than the prop.
@@kdrapertrucker _"Don't fly on them in cold weather, their driving systems suck."_
Did you mean their *deicing* systems? If so, that's true. Their deicing systems are notoriously -- fatally -- ineffective.
@@shreddder999 Unless it's got a synthetic cork or screw-top.
I love that your videos appear on Wednesday mornings, my time, at about 5 hours. This was really interesting and the fact that investigators were able to find that lost propeller is just another example of the unreasonable effectiveness of mathematics (math rules!). Mini Aircraft Investigation and Mentour are the only two channels about air crashes that I watch. BTW, one of your viewers turned me on to Mentour. These channels compliment each other in some sense. Both of you are gifted investigators and commentators, each with your own unique talents. Mentour satisfies my retired engineer's craving for technical details. You have the gift of breaking down complex scenarios in such a way that we non-pilot mortals can understand.
Forgive me, if I'm being cheeky in saying this, but I'd love to watch a collaboration between the two of you discussing some major event.
May I give you a tip for another channel that, judging by your comment I think may be "up your street"?
Have a look at the "Blancolirio" channel presented by Juan Browne. Factual aviation stories, well presented by a well qualified pilot. It's a great channel to learn from, too. All the best, safe travels 👍 ✈
@@restojon1 Thanks! I'll check it out.
And one more channel to check out if you wish: 74 Gear. From his 'about' page: "74 Gear / Pilot Kelsey, Boeing 747 Airline Pilot , All about aviation from passengers to pilots." And, yes, I, too, follow MAI and Mentour.
Fantastic! Road salt is prohibited from use at airports for this reason, and chlorinated chemicals in general are generally unwelcome. Even A-B-C fire extinguishers are prohibited due to corrosive effects on aluminum. Only B-C fire extinguishers are permitted in the AOA. I love videos like this because I teach many people how to operate safely in an airfield environment and references like this help me explain how small things can have an effect or why rules that may seem over-burdensome exist. It really helps when there is a rule that needs to be complied with if I have a concrete incident to point to that reinforces the importance.
I gather there are also severe restrictions on shipping gallium by air, because if it melted (I believe it melts at about 30 °C, so sitting on the tarmac on a hot day could do the job) and leaked from its container, it could alloy with the aluminum of the fuselage skin and create a weak spot.
Your narration makes watching these mini investigations a pleasure, and the content is always first class. Thank you
This channel gets better and better. Visuals are on point, and the commentry is clear and precise,with lots of information to absorb. Brilliant.
Those mathematicians were better detectives than Reddit and 4Chan combined.
I dunno.... 4chan does superpermutations better than mathematicians...
No shit Sherlock
I'm amazed, for sure. Corrosion is no fun on an aircraft, definitely!
@@Relkond I award you the best comment award 🏆 👏
You make great videos man!
Thank you!
Great presentation. While flying in helicopters in Hawaii a soldier in my unit had is M16 rifle fall out. A very serious issue for a fully automatic rifle that must be accounted for and secured. About 1500 soldiers were walking all over a very difficult part of the North Shore. One of the Lieutenants who was a math major got all the parameters and told us where to look in a 100 meter area. And yup, that’s where we found it. Gotta love math in a practical application. 👍
The subject of metal fatigue was the subject of 1948 book by Nevil Shute called No Highway In The Sky later made into a film starring Jimmy Stewart as an aeronautical engineer convinced that metal fatigue was going to cause catastrophic failure of an airframe during flight. Its an old relic of a movie that every aviation buff should see. Note that the late Mr. Stewart was a WW2 B17 pilot with 20 missions to his credit. He was eventually promoted to Lt General of the USAF Reserve. I hope all the channels viewers are wearing their red poppy's in recognition of Armistice/Remembrance day on Nov 11. Good video, well done!
This video is fantastic. Well done!👏
Youre my favourite aviation youtuber. You spend time on reports so much i adore your passion. Much love.
Who says you don’t need to know math? The mathematicians in this video are heroes. If the missing parts of the propellers weren’t found other propellers in service on other planes could have failed and led to crashes.
Thanks for giving mathematicians their due. Being taken for granted can add up!
I see whatcha did there.
As always, an informative vid. It's always a good thing when the passengers walk away.
what a story & so beautifully narrated!!
Love your channel, man. Thank you for adding a little bit of sunshine into my day. 👏👍❤️
Brilliant post. I didn't know about this one. And I really like the appreciation for mathematicians. I have a brother who is a mathematician, a nephew who has a degree in math, my son has a degree in math, as do I. I watched an MIT Open Course (?) earlier today on math. I couldn't quite follow it all although it was undergrad!
There was another accident involving prop disintegration on a similar aircraft that related to actual prop examination techniques. That accident had fatalities sadly. I don't have the link handy. You may be happy about this.
It's true that Safety Rules & Regulations are written in blood... But I always enjoy stories where no casualties happen.
This video title had me stressed out, glad this awesome crew got down safely!
One of the few channels that make videos about incidents. So many videos with tragic flights were everyone died, good job covering these 99% worst-case scenarios. Great to know this histories.
Appreciate your presentation.......All the best 👍
ATR has mechanical controls and hydraulics are used for landing gear(can be extended manually), flaps, braking, etc. It would have been a tough day nevertheless if the hydraulics were lost.
Well done to the crew for safely landing the plane.
congrats on 100 k
Thank you!
@@MiniAirCrashInvestigation cant wait to see that silver play button keep it up well hit 1million soon
You do an excellent job with these videos
Fantastic summary of this occurrence, thanks!
Excellent job! I really look forward to each new video your produce. Thanks for all the time and effort you put into your art!
Great work as always 👌
Nice video my friend!
As a Canadian, Val d'or is pronounced "Val door". while Dorval is pronounced “Dor-val" (as in valley).
As a a French Canadian, from Abitibi, Val D'Or is just pronounced Val dor. And Dorval is pronounced exactly the same but backward. Which is kinda funny. valdorvaldorval.
@@felixar90 Abitibi? I've got a great song for you. Wait, you've heard it already. Mouches noires la chanson de Wade Hemsworth.
@@amazing7633 Yes. Although Little Abitibi River is in North Ontario-i-o. I live in the Abitibi region of Quebec. Near the Abitibi Lake which flows into the Abitibi River.
>as a canadian
It's a french name
4:08 Just short information about the ATR controlles. The ATR is a cable controlled plane. The hydraulic is just used to work the flaps and landing gear.
Always happy to hear that everyone survived.
Great video, had not heard of this before.👏🙂
5:27
"Link on your screen right now"
Perfect timing.
Another interesting episode, sweet
Deformation mechanics (especially fatigue crack propagation) were a specialty of mine back in the mid-eighties as a materials engineer. It's amazing how cracks propagating from material defects (especially pitting and inclusions) can cause failures at levels so far below actual strength limits simply due to cyclical fatigue. This was not fully appreciated until after the crash of the Dehavilland Comets in the early fifties.
Excellent narration as always!
One minor quibble: "Quebec" ought to be pronounced either as "kuh-BECK", "kay-BECK" (which is the French-Canadian pronunciation), or "kwa-BECK", rather than "kyu".
Also, as @MarcDennis and @dmav522 noted, "Val d'Or" (literally Golden Valley) is pronounced like "Val Door".
"Kwa-beck" is NewYorker/NewEnglander pronunciation
Love your channel!
Very well put together! Keep up the great work!
Your videos get better every time! Well done.
I had an old pickup throw a fan blade straight up through the hood on the freeway. That was scary. This is like ×1000 and in the air. Eeek!
! ! ! ALMOST UNBELIEVABLE ! ! !
! ! ! AWESOME REPORT ! ! !
My parents are mathematicians but I screw math up because I sometimes switch the order of the individual digits in a number. In any case, I have a hint for being able to always know where your pocket things (like your wallet) are. I always put all of mine into a plastic container and put it near the door. When I leave, I simply put all the stuff in the container into my pockets and can rest assured that I'm not forgetting anything. Then, when I come home, I take those pocket things out of my pockets again and put them back into the plastic container. There are lots of things that can be done through checklists or by having everything that has to be done in a short amount of time together. Might as well save the real thinking for problems you hadn't anticipated because there's no way to be alive without having quite a number of those kinds of problems.
I still don't know why they don't put cameras on planes that let the pilots see the engines. If SpaceX can live stream during launches, cameras can work on a plane.
It’s quite easy
Cost and workload for pilots.
Cameras means more displays, more displays mean extra training. Extra training is expensive. Taking care of displays and cameras is expensive. Buying them in the first place is expensive
On top of what the other commenters said, the number of crashes that could have been avoided by having cameras all over is negligible, and you wouldn’t be able to view every part of the plane anyway. It’s just not worth doing.
@@Sashazur It might be worth doing, since planes already cost $10M-$100M. :) Even if a camera system costs $10,000, and 5 hours of training, that is nothing in comparison to the cost of the aircraft. Plus also, onboard AI could monitor the camera data on such a future aircraft design. That is just my opinion. Anyways, merry Christmas/happy holidays. 🎄🕎
Loved this episode like all of them! Of course we got another example of pilot skill and coolness under pressure - but this time the emphasis was a bit more on some science. Not just the clever maths employed in locating the propeller, but the metallurgy, physics and chemistry involved in designing, testing, manufacturing, monitoring and developing all parts of an aircraft but particularly really critical parts like prop blades. Mind you - and this is the thing with aircraft and aviation which totally differentiates it from all other forms of transport(excepting Space) - basically EVERYTHING is critical!!!!
A Brasilia from ASA was subject to the same thing in 1994 I think. They made an episode of it on Air crach investigation. Great job as always!
Mind I make a suggestion? I recommend looking into Avianca flight 011, it’s an interesting crash which resulted in a large loss of life but yet is never really mentioned. Also interesting circumstances surrounding it. Even a book was made about it a few years back too
There many videos on Avianca 011 that I have watched on Mayday and Air Disaster Investigation.
Got a future story for you. ZZ333. RAF Voyager KC2 that suddenly pitched down sharply. For once not a computer failure and actually it was the FBW that saved the plane
I’ll look into it thanks!
and theres a video out now about that!
The video looks amazing. You did very good job.
I love the detail and the focus here. We owe a debt to Neville Shute and his story No Highway in the Sky (made into a film) for raising the awareness of the public about metal fatigue back in the 1950s. There was a lot of scepticism at first. Famously the breakup of early Comet aircraft confirmed it.
Though Shute was actually right for the wrong reasons; he imagined fatigue happening from a nuclear reaction in the aluminum atoms IIRC.
Whew! You got me with the title of the video. Yay for the mathematicians (truly amazing accomplishment) and thank you for NOT walking us through all the equations. 😅😅
Great job I can already say!
"Looking for a needle in a haystack, when you don't know where the haystack is" - this one had me chuckle, I like your humour... (luckily no one got hurt here, so there's room for it)
A story well told, and thankfully with a happy ending. Good job 👍🏻
Your best video yet!
I worked in the aluminum industry a while ago. One time there had been rumors, that we would get contracts by the aero industry. As someone with privat pilot background and somewhat being an aircraft nerd, I was excited and shocked at the same time. Excited for obvious reasons, but shocked because I knew about the high safety responibilitys and my doubts about if my direct superiours would know aswell. Anyways, the contract never came, so there is that.
This video shows the importance of regular non destructive testings and inspections not only in aviation but in all fields of engineering and construction.
At the time of the accident, there was no non destructive testing available to find the corrosion. This includes visual inspection, as the lead wool that was used for the individual blade balance did not need to be removed, it was also not encouraged to be completely remove due to possible mechanical damage.
Congratulations to 100k subs!
An incredible level of detail. And thank you for praising mathematicians. I only have a bachelor's degree in mathematics and it made my brain hurt.
Mini Air Crash Investigation, thank you for your efforts. May you and yours stay well and prosper.
Fascinating!👏👏👏
Interesting regarding the cork. Cork is no longer washed or steamed with chlorinated water as it produces TCA - the compound that causes the 'corked taint in wine.
However for industrial use production of the cork is very different.
Most fatigue cracks occur on exterior surfaces where stresses are usually the greatest. For example, the outside of a shaft in torsion experiences the greatest shear stress and can be detected using visual or fluorescent dye penetration inspections. Corrosion as in this case initiates cracks in nontypical places. Slag inclusions inside components also create fatigue cracking not visible in the surface, need more sophisticated detection methods (x-rays?) and have caused unexpected failures in turbine engine disks.
And yet a yet later on Atlantic Southeast Airlines Flight 529, a nearly identical blade corrosion issue happened with much more serious consequences. :(
Correct, but the blade that failed on the ASA flight had issues passing the original Ultra Sound inspection from the first two failures. It is possible that some of the corrosion pitting on the blade caused it to fail about 17 months after this in August 1995.
This accident is eerily familiar. The USMC C-130 tanker that crashed in Mississippi (?) recently was brought down by a thrown #2 propeller (metal corrosion) that went thorough the fuselage, consequently the skin started coming off, then a gearbox failed on #3 due to vibration and prop #3 came off causing the cockpit area to break off the fuselage.
Man! That's wild! A cork. Glad no one was in that seat.
"cumulatively accumulated" is a phrase I never knew I needed to hear
Thanks again MACI.
I wouldn’t argue with the findings - when you speak of low level chemistry reactions, could acid content in the air moisture content contribute at? The pit like indentation also occurs on the back of propellers in marine vessels, it’s called cavitation. Just compare the issue of compression and vacuum front and rear of prop, then compare density of water and air - add in the relative speed of marine props and aeroplane props or screws as they were once called.
Excellent job.
Interesting way to balance things. Typically with balancing, they will remove material, usually by drilling/milling or with a laser, from points where the balancing machine determines. But I suppose it was designed this way for a reason.
Any material removed from the prop blade will change its shape thus aerodynamic characteristics (and stiffness, vibration resonances and so on). So other means had to be developed. Dynamic balance is also dependent on the mass distribution throughout the blade (where the material is removed). Consider balancing a car wheel. Mass is added, not subtracted.
I was eating pea-soup, watching this story.
The spoon were held in position in front of my mouth, mustache and beard (poor spoon), for a rather long time, as you told about the ordeal, from the bang, down to :..... And thankfully it did (held together until they landed). I did not eat the soup in that spoon, before that plane touched down!
I'm deeply impressed by your storytelling, the way you use your voice, it's just an awesome channel, where you present us for the fruits of your investigations! Love it :)
And what's the story about the 15 "nope" folks????
A piece of the propeller penetrating the fuselage is another night-mare scenario. But much more srvivable than having a wing torn off.
It really helps me to feel better about flying because I know the extent to which they investigate these crashes. "There is no such thing as 100% reliability.". Truth! But, thanks to investigations into incidents, we keep moving the march of 9's further every year.
I always liked the ATR, I guess it epitomizes the regional aircraft to me. But til now, I didn’t realize how small the wing is relative to the fuselage. This is the 2nd incident I’ve learned about where the cork in the propeller was the nugget.
"Looking for a needle... when you don't even know where the haystack is!"
Well from steel or iron water pipes it is known, that wood under lied to equalize the pipeline during installation leads to local pit corrosion in the steel or iron tube, due to organic acids formed when covered with earth and humidity, this can destroy iron tubes with 1 cm wall strength within 20 years.But water storages from the Bronze Age build entirely from wood lasted nearly 2800 years and where removed finally due to mud accumulation. So wood itself properly cut in winter, so as to reduce its sugar content, and probably treated with its own oil and resin can last very very long! Unfortunately when they removed it and put it in the museum of San Murezzan, St. Moritz Switzerland, they painted it with black coal tar and cut a big hole.
This incident reminds of a similar one with a Embraer I think in the US. Not sure anymore. But can remember the same cork and chlorine stuff. It’s not an ATR fail, it’s Hamilton Standard, the prop manufacturer.
Voice and vidéo are impeccable...big like
My brain shut off for a second and I read the thumbnail as "How a bit of chlorine ripped a fart"
4:05 There is a big missinformation. The ATR is a cable plane, no hydralics are used for the alerons, elevator or rudder. The only thing that would have not worked, would be the flaps and the hydraulics for the landinggear but this has a backup function.
I like these lesser known ones where the ending could have been horrible but the pilots (and luck) managed to save the day and everyone was okay. Maybe less dramatic than the big crashes but cool to see how even if something goes horribly wrong, a lot of the time things work out. I’m Canadian and had never heard of this one.
Near miss MACI videos! The pilots' crisis management was great. Wild story.
You give the impression that the number two engine was kept running which seems impossible given the blade imbalance. Indeed a fascinating story digging back to the root cause.
After the portion of the blade broke off, the rest of the propeller imbalance caused it to break off the front of the gear box and leave the aircraft. So there was no thrust from the right/#2 engine.
8:53 Turbo prop animation on left side of video is playing behind the plane wing, meaning it looks weird. I don't know what animation software this is but that would be a rather odd glitch to fly around with in real life! 😅😊👍
There's also the American Airlines Flight 191 incident where metal fatigue (stress crack) caused an entire engine to rip away during takeoff. Although that was a result of airlines caring more about savings vs. safety rather than a chemical reaction.
Imagine being in the seat next to the one that got sliced in half by the propeller blade...
Good to see that all these don't end in catastrophic event😁💜
Stuff the number crunchers, the pilots were the heroes here. Wise decision not to stress the hull any further than needed, but testament to a good design.
Interesting video. The sleuth work required to figure out where the corrosion came from is impressive.
For the record, there's no such place as Val-Dior. The place is called Val-Dor
What a pleasure to listen to a video where the “speaker“ is a human being with mastery of English - the bots And ESL speakers need editors