Cessna 140 Stall/Spin Accident Wayne NE

it's monday may 23rd my name's juan brown you're watching the blancolirio channel getting a lot of questions about the tragic loss of tom dafoe in his 1946 cessna 140 while performing a traditional stole demonstration at wayne nebraska this weekend so what i witnessed out there at wayne nebraska was a classic stall spin event while on final there were well there were three aircraft in the pattern the first aircraft had just landed so at the time of the accident there were two aircraft in a right-hand pattern for a grass runway that was heading into the wind a headwind a gusting headwind more on that in a minute two aircraft in the pattern the aircraft ahead was a zenith stole aircraft and then tom's aircraft the cessna 140. the zenith stole aircraft has a considerably slower stall speed than the cessna 140. the zenith was flying a relatively slow final approach for a traditional stole landing demonstration tom cut his pattern relatively short and was following close behind the zenith aircraft he rolled out on final and it was as i remember from my eyewitness account there was a slight bit of s turn on behalf of tom to try to remain behind the um aircraft ahead of him he had adequate spacing but the difference in speed meant he would have been closing on him but with nose high slow air speed it initially appeared that tom was going to break out of the pattern to the right and start all over but i'm afraid that was the beginning of the stall spin sequence for tom in the cessna 140 with the nose high the right wing began to turn the aircraft and then the aircraft dropped off and did about a half a turn three quarter of a turn spin into the ground now what's the typical normal human reaction when you get into one of these situations is unfortunately all of us unless we're really really up on this we tend to um pick up the wing that's fallen with the aileron what does that do that just exacerbates the situation and i i'm not sure that tom did this in this situation people investigators be looking closely there was some video capture of the event but typically what happens is you try to pick up the wing that's dropping with the aileron that increases the camber on the wing that is stalling in this case the right hand wing and increases the induced drag on that wing which further exacerbates the situation accelerating the spin entry along with that once once you see that ground coming up the natural human instinct is to just simply pull up on the controls and that just tends to further exacerbate the situation and do effectively a snap roll right into the ground there's no way you could possibly recover from that altitude even from pattern altitude if in the event that you get into a full fully developed spin entry a little bit about the event itself the mayday stole drag is a stole drag competition a stole drag competition is a three day event the first day thursday involves all training we had eight new pilots to stole drag racing to train up on thursday we got through that training on thursday before the winds went out of limits for stole drag racing and out of those eight new pilots uh two of them did not make the cut now tom in his cessna 140 he has been previously qualified as a stole drag racer so he was an experienced stol drag racer tom is what i would call a fast burner he has a little less than 500 hours but in that system 140 he has flown that 140 in a lot of very challenging conditions back country stole type conditions so he is not a rookie pilot the stole drag practice was cancelled due to winds being out of limits there is a 10 knot crosswind limit and a 10 knot tailwind limit for stole drag racing because you're running two aircraft side by side once you get the racing started after everybody's been trained up they run down side by side down the 2 000 foot long course stop turn around and come back and to the start finish line later on that afternoon it was decided that the guys all wanted to go flying and do a traditional stole demonstration on the grass runway the grass runway was noted closed at the time but because that was wavered or nodum closed because it crossed i'll show you here on the map it crossed our stole drag runway since we weren't doing the stole drags anymore the faa approved our operation off of the closed grass runway to do a traditional stole demonstration so here's a picture of the wayne airport the red indicates the stole drag course two thousand feet long with nine hundred or almost one thousand foot overruns on each side parallel to the runway two three 0 5 runway so since they were no longer using the stole drag course it was approved by the faa to use the grass runway that was notem close and everybody agreed to do a right hand pattern to keep the traffic away from the crowd located back here instead of launching 20 aircraft into the pattern at once for a traditional stole demonstration it was decided the pilots broke themselves up into groups of five aircraft so they only had five aircraft total in the pattern at once at the time of the accident there were two aircraft in the pattern so we were just talking about this with summer intern kellen here he was getting some time here in the luskim the first thing we go out and do is practice slow flight stalls and falls the hazards of hanging it on the prop if you will is that you are operating and this is for all the non-pilots out there and everybody else that's learning to fly a quick refresher course that the problem with hanging it on the prop if you will or flying very slow is that you're in the region of reverse command there are two drag curves associated with an aircraft kellen which one is the drag curve associated with induced lift induced drag is going to be this drag curve right here correct and parasite drag would be this other drag curve right so this is speed and this is an increase of drag so parasite drag is just that drag like you stick your hand out the window and and it's uh dragging on the form of your hand parasite dr a correction induced drag is that in drag produced by the process of creating lift on the wing as you slow down more and more you create more and more induced drag demanding more lift out of that wing and that's manifested itself in in wing tip vortices and so if you if you put these two curves together you get a a drag curve and if you're operating to the left of this low point here you're in the region of reverse command in other words in order to go slower kellen what do you got to do with your power you got to add more power you gotta add more power to go slower in the normal area of operation if you wanna slow down what do you do with the power you have to decrease the power decrease the power and the aircraft will slow down or raise the nose pitch and power so why do you want to operate in the area of reverse command well you want to land as slow as possible for the shortest possible distance in in your back country flying now what happens when you add wind gusts to the problem the gust factor usually and big airplanes do this people add a certain amount of air speed to their reference air speed to come into land in gusty conditions why because of it's not the wind gust itself when it blasts the airplane and you'll see your airspeed indicator bouncing around it's when that gust of wind stops it's when the wind dies off that's when you got a problem that's technically known as a decreasing headwind shear and if you're hanging if you're in the area of reverse command and you're only a few knots a few miles an hour above stall speed and that wind dies off on you all the time the aircraft doesn't have time to respond quickly to the change of what's going on around it and so you can very quickly find yourself in a stalled situation remember you can stall an aircraft at any airspeed but it will and any attitude it will only stall at one critical angle of attack the normal recommended faa approach speed is 1.3 vso or 1.3 times your power off stall speed so let's say for example your power off stall speed is 50 miles an hour five times three is 15 that would be 65 mile an hour approach speed then you would add your additives for gusty winds on top of that so if you're operating deep into the region of reverse command you're removing that safety buffer so the better course of action is to approach at the appropriate speed and then bleed off that energy very close to your landing point to achieve your short field performance and the same thing goes for takeoff as well on these stole demonstrations you want to get your shortest takeoff distance but then lower the nose and accelerate and ground effect and then just do a normal climb out no need to hang it on the prop and the only way that you can truly verify what the actual stall speed of your craft of your aircraft is is to go out there and do power off stalls and look and see at what indicated airspeed the aircraft consistently stalls at what's in the book may be considerably different than what your aircraft actually performs like so let's keep the dafoe family in our hopes and prayers a special thanks to the clemens aviation family for helping taking care of getting everybody back in home after this tragic accident thanks so much for your support of this channel see you here

Channel: blancolirio

Views: 228,943

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Id: LpPFfZ76v4Q

Length: 10min 56sec (656 seconds)

Published: Tue May 24 2022