What appears to be a practice or demonstration drop by a Brazilian Embraer EMB-202A Ipanema ended with the wings folding and the pilot surviving with serious, but not life-threatening, injuries. The Ipanema is an aerial application plane but this aircraft appears to dump its load rather than spray it.
In the crash sequence, the airplane flies the centerline of a rough air strip and starts jettisoning a load of liquid from the belly rather than the application nozzles on the wings. About halfway through the drop, the aircraft pitches up and the wings fold. Authorities are undoubtedly investigating.
Looks like a high-speed run. As the load is dropped the pilot pushes to maintain altitude, airspeed exceeds the manoeuvring speed and voila, wings depart with the merest hint of g. A smattering of fatigue may also have been a factor. Almost analogous to the Phantom pilot at Abingdon, doing a loop he attempted to re-position on the display line by pushing at the top while inverted – the airspeed increased to a value which made it impossible for the loop to be completed successfully, which it wasn’t!
“exceeds the manoeuvring speed and voila, wings depart with the merest hint of g.” That sounds impressive but your understanding of maneuvering speed and its relationship to G clearly requires more work.
What a tribute to the integrity of the cockpit!
IMHO, you guys have been scammed. Remember the video of the aerobatic pilot who lost a wing in flight and somehow landed safely? As we now know, the airplane in that flight sequence was a model. Having been a serious aerobatic competitor, I cannot imagine a set of circumstances where one wing, LET ALONE BOTH, fail upwards. Metal fatigue coincidentally reaching a critical point on both wings at the exact same time? The climb had just begun prior to the failure, it was not an extreme maneuver, and I doubt that more than a couple of G’s would have been placed on the airplane. In an ag plane that’s built for abuse, there’s no way that 2 G’s is going to fold a wing, let alone, coincidentally, both at the same time. Re exceeding maneuvering speed, it’s not the speed itself that is dangerous. It’s when ‘full deflection of controls is applied. There’s no way that the fairly mild initiation of the climb involved full deflection. Utility aircraft are designed to withstand 4.4 G’s. It would have had to have been an almost immediate pullup to vertical.
Elevators are in neutral position throughout. Excellent call, Marshall.
If you have a ton or so of water, and dump it, something magic will happen without the pilot moving the stick at all.
I see no evidence that this video is a scam. There are many things that could cause the wings to fold as they did video. Both wings folding simply depends on the aircraft design and actual failure mode – in this case I suspect the fuselage carry through structure failed.
We don’t know much about this accident, but other factors may have led to the failure besides simple over-G. If the aircraft were exceeding VNE and/or experienced a severe gust-load incident, it could have very-well been over-stressed without a significant pull-up. Also, some aircraft can pull maxim G with very little actual control surface deflection. For example, in my RV-8 at speeds well above maneuvering speed, it only takes a few degrees of elevator deflection to approach the aerobatic limit of 6 G’s. In addition, we don’t know how the CG of the aircraft may have changed during the water dump.
“It would have had to have been an almost immediate pullup to vertical.”
Don’t confuse pitch angle with G-loading. If something caused an “instantaneous” overload such as a wind-gust, it doesn’t really matter how much pitch-motion the actual aircraft does through. Also, judging g-loading from watching a video can be very deceiving.
There is data from this accident on ASN, so it does appear to be real. In addition, this same aircraft was apparently damaged in a prior landing incident in 2017. A faulty repair could also have led to the wing-folding.
Indeed, it never happens: https://www.military.com/video/aircraft/military-aircraft/c-130-tanker-loses-wings-crashes/3152191853001
Except when it sadly does.
Exactly. There was the T-34A incident in 1999. Analysis of the video recovered estimates them at 12 G rolling. There was also some metal fatigue/stress cracking.
I am familiar with the RC ‘scam’ video you reference. I don’t think that is what we have here. Nor is this the first video of an aircraft losing both wings simultaneously in this manner (there was a C-130 water bomber that broke up in very similar circumstances to this one).
Maybe there was a fatigue issue, but this sequence clearly shows several things happening that together can lead to structural failure like this. And it certainly does NOT require full deflection of controls.
Yes, the video was an RC Model. But a similar incident occurred in real life top British aerobatic pilot Neil Williams.
http://www.dauntless-soft.com/products/freebies/zlinwingfailure/itsfake.asp
Empty Weight is 2249. Max capacity is 250 gallons of liquid (about 2000 pounds of water). So at 2G, there is about 8500 pounds of lift. Dumping 2000 pounds means you have 8500 pounds of lift with only 2249 pounds of aircraft, so you immediately are at 3.8G. If at 4G when you dump, you end up over 7G.
I agree with Marshall Friedman that things don’t quite seem quite right about this accident. The maneuver during which the wings folded did not appear to be extreme and should not have overloaded the airframe; however, both wings of an airplane can fail simultaneously if subjected to a severe overload. Additionally, depending on the structural design of the airplane, the failure of one wing could induce the failure of the other; however, I would think that simultaneous failure is rare indeed. Unless the wreckage shown in the video is the result of another crash, I’m guessing that this was a real event involving a real airplane.
I admit I was fooled by the safe landing in the one wing plane also.
On the other hand, there was a mid air years ago and an Israeli F-14 DID lose a right wing and the pilot DID bring it to a safe landing.
Another tip on this video is this is a strut braced wing which is close to failure proof unless there are extenuating circumstances like corrosion or maintenance error. For both to fail simultaneously would be statistically almost impossible.
The EMB-202B does not have strut braced wings!
Thanks for the correction. I went back and looked at the video. It was fuzzy and I misinterpreted. What I was seeing was the spray boom
It was an F-15 not an F-14. But there is a world of difference between an F-15 and an ag plane. Much of the F-15’s fuselage is a lifting body and produces lift in addition to the wings. I’m going to bet this plane’s fuselage provides no additional lift.
I know the jet fighter’s fuselage provides additional lift that is not the case in a GA aircraft but I mentioned it as it was amazing flying and ability of the jet to take a beating and still get home safe.
It was amazing, yet not amazing flying. I remember the pilot, upon landing, being surprised he’d lost a wing during flight. He barely noticed any difference in the controls.
It’s not an agplane. It’s a SEAT (Single Engine Air Tanker), for firefighting, which is the reason it dumps its load rather than spraying it,
A good friend of mine (maybe he’ll weigh in here) found this accident listed in the ASN database for Dec 5, 2021 which would tend to indicate this video is not a fake. https://aviation-safety.net/wikibase/270409 It is listed on the database as an AG plane. According to the narrative the pilot had to abandon his spray mission due to weather so he elected to dump the water portion of his load prior to landing.
Having worked in agriculture including aerial application familiarity, corrosion from exposure to some pretty bad acting chemicals combined with age (do we know how old the plane was or how it had been used), maintenance, and repairs, and history of use/abuse, the observed destruction could have happened, especially considering it was not in the US where the rules are relatively strict and strictly enforced.
exactly. Well said. Ag chemicals, expecially ammonia nitrate, are very corrosive. Notice the tank appears to be right above the wing spar.
I have never flown these type of aircraft so not sure about design. In my opinion fatigue and corrosion due to chemicals coupled to poor maintenance could well be a factor. I recall in 2006 there was a C130 fighting fires in Australia. I believe the C130 belonged to a Canadian company – Coulson. On dumping the load, followed by a small pitch up, the wings broke. This was attributed to cracks in the C-section. I was working with at a civilian Company at the time that had a fleet of 10x C130s. All had to go for C-section inspections and some had to be replaced due to the same issue. I see a lot of similarities in this crash to the one posted here. I would be very interested to see the outcome of this investigation. Herewith some links to the C130 accident (RIP all). https://www.youtube.com/watch?v=n06WNSS4tFs http://www.iasa.com.au/folders/Publications/Legal_Issues/PearblossomC130.html
The physics look right to me. Very high speed low pass with a sharp pull up in the wings folded. Yes, looks like corrosion.
I’m not very familiar with the EMB-202 but I’ve worked with lots of guys that fly the AT-802. There’s a tremendous amount of pitch up motion that happens when the load comes out. It takes quite a while before guys get the trick of pitching forward when that close to the ground already.
1) If the EMB carries similar amounts to the Air Tractor, he’s losing roughly 700 gallons of water in just under 4 seconds (that’s just over 5,800 lbs of weight). That alone can be a stress on the plane. ANY increase in G (and yes, it looks like the elevator “flicks” up near the end of his drop) can cause structural failures. If a aerial applicator dispenses his load at just 2 G, now they’re not just losing 5,800 lbs but 11,600 lbs. And though it doesn’t look like he’s pulling G’s for the first part of the drop, he definitely loads the plane up near the end of his drop.
2) As mentioned in my previous point, if you watch the end of his drop closely, the elevator flicks up for a brief moment, followed by immediate wing separation.
3) Lastly, it’s not uncommon to lose one wing followed very closely (almost immediately) by the other. Another example was Tanker 130 back in 2002 near Walker, CA
Glad to hear he’ll be okay.
Seems to me the wing carry-through structure has had a fatigue failure. This would explain the double wing fold. See 0.28 seconds on the video clip for the visual of the piece.
The first version of the 200 series came out in 1971, still produced. The 202A came out in 2004 so, with this failure, it must have been sorely abused and overloaded in its operational life (or a manufacturing defect).
According to ASN, this same airframe was substantially damaged in a landing accident in 2017 when it hit a fence. It’s possible that it was incorrectly repaired from that incident.
metal fatigue/ corrosion in the center carry through structure.
If it was a scam the water effects were spot on. It would have to be in slo mo to simulate the water drop etc. A scale model water would have dissipated way more quickly.
At 27 seconds into the video, you can see the main wing spar “thru structure” lying on the ground. They eyebolts are the midpoint of the span. You can clearly see the spar sheared off at each outer wing saddle, and did NOT fail in the middle. A diagram of this piece is in the EMB202 service manual. Pretty amazing each side failed at the same time, given time, corrosion, fatigue, and manufacturing variations.
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