FlyWire Accident Review PA 30 N8357Y Loss of Control Inflight

[Music] the prelim is out on the twin comanche 8357 loss of control in flight the accident that happened just north of enid oklahoma on 17 march 22. stick with the sunflywire as we take a look at that hi i'm scott purdue and today on flywire we're going to take a closer look at the loss of control in flight of this twin comanche that happened in in enid oklahoma just north of enid oklahoma i did a quick look on this accident several weeks ago and now we know more detail so here are the facts the accident pilot was flying his family from texas valley home to nebraska they did a fuel stop in minerals texas and then took off headed north the aircraft was on a vfr flight and the pilot was not talking to atc i do that myself the pilot was multi-engine rated but he did not hold an instrument rating and there was weather along their route of flight following the progress of the flight they didn't really remain at any particular altitude very long and flew for a while up and down i don't translate this as a problem holding altitude frankly but more as a search for an altitude that he could stay vfr the pilot eventually topped out just over 16 500 but again the aircraft didn't remain there for very long before starting down a quick word about oxygen here oxygen uses required by the faa is probably a good idea when i did a quick look the quick look uh at the accident i mentioned that the pilot had been above 12 500 for less than 15 minutes total and didn't think that hypoxia was a likely factor except for the possible impairment of judgment i did not refer to the actual rig and given the response to the video i probably should have the governing regulation is found is 91.211 supplemental oxygen and what the what that uh reg says is that for calvin pressures between 12 5 and 14 000 the pilot must use supplemental oxygen after 30 minutes and above 14 000 the pilot must use it the entire time and above 15 000 each occupant must be provided supplemental oxygen for the accident aircraft it does not appear that oxygen was used the ntsb didn't say anything about it being found in the airplane i stand by my comment that i don't believe hypoxia itself was a factor at this time but perhaps the final report will have a toxicology report to determine the actual blood nation the time of useful consciousness at 16 5 is 30 minutes or more and for a normal human and the actual exposure in this case was approximately 15 minutes poor aerodynamical aeronautical decision making was a factor and oxygen deprivation would have made that worse but make no mistake time of useful consciousness and incapacitation was going to be a factor very soon if the pilot continued on this course but it was unlikely that this was the proximate issue in the loss of control it appears the aircraft crested the main portion of the depicted brain and was climbing as much as a thousand feet per minute passing through 14 000 feet this seems to me to be rather high climb rate for that altitude with the normally aspirated engine maybe he's trying to climb the clouds shortly after reaching 16 000 the airplane began a series of turns one has to surmise these turns were to avoid going into the clouds encountered at that particular level and i've been there before trying to do that at no time did the airplane turn back and reverse course out of the area of imc the pilot had no way of knowing the tops of the clouds along his proposed flight path that is actually really pretty hard to judge that looking ahead of you looking at the adsb record of the last four minutes of flight the series of turns became more desperate appeared to be in my my view and altitude control did become erratic on the whole the airplane was descending but at one point it was climbing nearly 4 500 feet per minute so it was up and down and drastically at one point 4500 feet per minute had to slow down for that at 21 30 and 10 seconds the aircraft began turning back to the east and at 21 30 21 seconds at 16 10.65 it seems to be at the moment the pilot appears to have lost control the aircraft turned 167 degrees and lost 475 feet in one second definitely not a normal rate of turn the descent rate began increasing and the last 80 sb hit recorded a decent of 30 000 feet per minute this is a speed the aircraft cannot sustain and structural integrity becomes an issue a witness reported that he thought the their the engines were revving and this is a common misperception when engines at a high rpm like cruise rpm rapidly rotate through the plane of noi or the noise footprint past the stationary observer you'll hear that juan he reported he looked up and saw the airplane come straight down in a right-handed nose-down spin he tracked the airplane as long as he could losing sight just before just prior to impact the impact site was spread across several fields with the main wreckage inverted located in a field on the west side of a creek this consisted of the ford fuselage the cabin the baggage compartment the left and right wings and the engines the majority of the engines the fuselage was crushed aft and fragmented showing evidence of a near vertical impact as it pushed the nose in the air fuselage and empinage inboard sections of the stabilator were broken and connected to the main wreckage by the flight control and trim cables they were not severed both wings were broken at about five feet inboard of the wingtip and the fracture points showed upward bending and aft twisting with fractures consistent with a positive overload failure the vertical stabilizer had impact marks and paint along the leading edge consistent with some component of the airframe striking it prior to ground impact outboard sections of the wing along with the tip tanks which were located 600 feet southeast of the main wreckage actually sort of in line with where the wind was blowing um in the same area the left and right propellers of the engine were found the left prop hub was broken and one propeller blade was not attached and there was no damage to that particular blade the other blade remaining in the hub showed s-bending and cord wise scratches and that trailing edge gouges two inches of the outboard tip were missing the hub was attached to the crankshaft flange with three inches of the crankshaft still attached the right propeller was intact and attached to the flange with three inches of the crankshaft and both blades were bent forward with cord wise scratches and trailing edge gouges interesting both props basically were ripped out of the engines broken out of the engines those are the facts of the case i think this is it's obvious that this is a loss of control in flight one of my commenter uh one commentator on my quick look video was a pa-30 uh twinkamanchi pilot and he surmised that the airplane was likely trimmed in the climb and then the trim tab froze leading to the stall and the departure i think that is a stretch given the circumstances of the crash the typical ga airplane will lose approximately 200 feet per second in a spin that equates to about 12 000 feet per minute decent rate that's pretty fast but the airspeed of the airplane is not extraordinarily high the air speed down is it's something on the order of 200 knots down but the actual eric spare speed experienced by the airframe and a fully developed spin may vary between 50 to 80 knots which is actually what we saw after the looks like the breakup happened not enough for structural failure but the highest ground speed recorded by the adsb in this case was in excess of 281.81 knots even allowing for winds at that altitude of about 20 to 30 knots this would still be a speed well above the 178 knot redline for the pa-30 the structural failure occurred prior to the spin i'm pretty sure it is possible the aircraft's airplane spun was recovered and the overspeed was experienced in the dive recovery however this is inconsistent with the speed and heading record prior to the 21 30 21 second event uh where we think you think you lost control at that point the high speed abruptly ended losing 100 knots and eight seconds 66 knots in the next three seconds and a further 53 knots in the last recorded adsb hit so it went from about 280 to about 63 and what is that 11 12 seconds this abrupt profile is consistent with an out of control dive followed by a spin in this case the spin was i think is the result of the wings reaching the breaking point and failing five feet in board of the wingtip the subsequent aerodynamic imbalance led to the near vertical nose down spin from my perspective the pilot probably lost control of the aircraft during the attempt to descend through disorientable disorientation in clouds subsequently losing control of the flight path this resulted in a severe nose down dive either the sheer speed attained in the dive or an abrupt pull-up attempt at recovery initiated by the pilot was the likely cause of structural failure given the upward bending of the spar at the fracture point as well as the failure of the empanadas instead of just ripping off this way the upward bending of the spar leads me to consider that a pull-up was most likely the cause the intact horizontal and vertical sections attached by cables to the main fuselage are further evidence of an attempt to pull out of the dive just prior to the structural failure an overload condition would definitely exhibit a failure in the wing spar in this case just outboard of the engine in the cells but a pull-up would also see the fuselage in the empanadas break or deform near the high stress points which is induced by the elevator authority just forward of the elevator itself this is a there is a big bending moment there too that's concentrated there between the wing and the tail so it doesn't break at the tail and the wing it breaks generally somewhere ahead of the uh empanadas the pilot flew the airplane into a situation that was above his ability or training to deal with that's the bottom line he's not he is not the first to react promptly uh to a loss of control in flight in imc i'm not even sure that uprt training would have been able to save the day in this situation if the pilot had been able to recover from the unusual attitude of the nose load dive he still would have had to contend with orientation and maintaining level flight in the clouds he was not instrument rated and this situation was a deal breaker if you're not instrument rated avoid imc at all costs if it means landing and spending a night or two in the hotel or renting a car and driving home that's going to be a whole lot better result than being included in an ntsb database another lesson learned here is that trying to outclimb a storm is a dubious prospect at best and flying with oxygen in the teens or or above has odds worse than russian relay it's not going to end well even if you only spend a little bit amount of time there the oxygen deprivation is a huge problem i think the old adage that time despair go by air probably has relevance here you have to have some judgment about what you can do and what you can't do and what you shouldn't do even if it's illegal you shouldn't do i'd like to thank my patreon supporters right here and if you'd like to support the channel i'll leave a link below to the flywire patreon page i appreciate y'all thanks for watching and i'll see you next time on flywire

Channel: FlyWire- scott perdue

Views: 28,840

Keywords: FlyWire Accident Review, PA 30 N8357Y Loss of Control Inflight, flywire online, flywire youtube, airplane spin, spinning a GA airplane, departure, controlled flight, recover from a spin, Spin a Bonanza, spinning a bonanza, Spin a Twin, Flywire, scott perdue

Id: y9Reve0RQuw

Length: 13min 3sec (783 seconds)

Published: Sat Apr 16 2022