Early Analysis: PC-12 In-flight Breakup Over Stagecoach, Nevada

On February 25, a Pilatus PC-12 crashed about 14 minutes after departure. Sadly all five people on board the airplane perished in the accident. The AOPA Air Safety Institute gives an early look into the factors surrounding the crash and addresses notable portions of the flight and highlights areas the NTSB will likely probe.
0:00 Intro
0:28 Likely Causes
0:35 The Conditions
1:54 Likely Causes
2:01 Aggressive Stall
3:02 Icing
4:10 Incorrect Unusual Attitude Recovery
4:46 Turbulence
5:13 Spatial Disorientation
5:49 Takeaways
7:35 Minimum Climb Speed in Icing
9:07 Outro
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[@steveo1kinevo]

A lot of great things to think about by watching this video to stay safe on future flights. Thanks for the analysis!

[@AirSafetyInstitute]

Appreciate it, Steveo!

[@michaeljohn8905]

No doubt . I grew up as a teen in the mid 80,$ and videos like this are just pure GOLD . I hope other pilots are watching these great videos. I have to say I think I’ve stayed more Proficient and just aware since this type of social media type learning has been introduced. I had to go to libraries & keep flight subscriptions or read the latest issue of Flying magazine to hear of things like this. You don’t realize how far we have come in the last 20 years it’s just great. Stay safe boys n girls !

[@article1934]

what is there to think about here? experienced pilot falls out of the sky and you have no idea why this happened.... not a clue. The entire aviation industry is a swirling vortex of false hope that some random thing isn't gonna knock you out of the sky.

[@cujet]

As a PC12 operator, my money is on icing. Despite the FIKI claims, the PC12 is not capable of flying in all types of weather. Even with 100% functional de-ice boots and prop blade root heaters, we've experienced an icing induced inability to climb over 19-20K. Ice builds up on the prop, horrible vibrations result, the reduced thrust compounds the reduced lift of iced up wings and tail. It gets ugly very fast. Add in the fact that the exhaust plume spirals over the right wing, warming the root, and not over the left wing, not a big deal, but it can affect fuel icing. An ice induced loss of control is clearly a possibility, especially if one wing de-ice valve has failed. In my opinion, all the clues are there. Additionally, this is why we use liberal amounts of ICE-X 2 on the boots. It really does help. The in flight breakup was a severe over stress. If I remember correctly, the last one broke the wing in a similar manner, and that took 14G's.

[@richardmcspadden9189]

Thanks for the added insight on PC-12 icing systems.

[@garyurban5373]

If this was the case, the prop would have required an asymmetric accumulation of ice, and that would have required a failure of the aircraft's prop de-ice system. This means the pilot ignored his amber deice CAWS annunciation for an extended period of time as the aircraft continuously lost performance, and continually climbed. This loss of performance would be reflected in the ADS-B data.

[@gendaminoru3195]

What would you say about an STC for electrically heated leading edges? I myself don't like watch and worrying about whether or not boots are going to clear the ice. heated edges would be anti-ice and/or de-ice, whereas boots are ONLY de-ice. No one like messing with TKS fluids, but there is an extra accessory pad on the PT6 for a dedicated alternator, and yes there should be a Beechjet style ice sensor with the system to automate. This is a serious question and any replies are welcome and encouraged.

[@jacknisen]

Which last one? Amarillo?

[@cujet]

@@garyurban5373 I know first hand that the prop blades will build up ice outside of the functional heaters. The result is exceptionally uncomfortable. Both from a vibration point of view, and performance.

[@thedlalwani]

The pilot onboard was a check pilot in my flight school, and one of the best people I have had the good fortune to fly with. Very knowledgeable about his procedures and always a fun guy to be around. Very unfortunate for this to have happened. May his soul rest in peace. 🙏

[@A300freightpilot]

Key word is "flight school". Theoretical knowledge of everything doesn't replace experience.

[@mikearakelian6368]

I never was much of a gambler; wait n see for me

[@FSEVENMAN]

Doesn't matter how nice a person is that has nothing to do with the fact that this was either ignorance or arrogance, we all need to remember we are not airline pilots flying heavy duty Boeing aircraft. Single pilot into weather at night IFR with a sigmetl? This guy was an asshole, it was an obvious no go decision....😊

[@Brotha00]

Unfortunate incident. Thanks for sharing your experience and reminding us of the man’s humanity. RIP

[@RobertJamesChinneryH]

Another U tube fantasy

[@burntsider8457]

In my instrument training I was taught that you have three enemies in flight: Weather, Night, Mountains. I was warned to never face any two of those three at the same time.

[@blackhawks81H]

That's a good policy.. When single pilot especially. Any of the following: General bad weather aka rain, clouds, etc , icing of ANY kind, terrain, night. Pick one. Never more than one. If more than one of those things exists. Pick tomorrow.

[@fistfullamullah]

Those are great words, but as a former freight pilot (multi), and then air ambulance pilot in a PC12NG, I can tell you that these are all everyday realities of what we do. I have the misfortune of more than 1000hr in the PC12NG as an air ambulance pilot. At best the PC12NG is a woeful aircraft. Underpowered and deice systems that are marginal at best. I’ve flown turbine twins in heavy ice and turbulence as a freight pilot that could barely stay in the air. Some others haven’t been so lucky. For as long as companies insist on cheap single engine transportation, the fine margins of safety will always be pushed to the extreme!

[@davidwhite8633]

@@fistfullamullahNever flown a PC -12 , does it have de-icing on the tail horizontal stabilizer ? Any ice on the wing means more on the tail - which couldn’t be seen by the pilot and would nose the ship down straight away at stall . Of course, severe turbulence could have been a possibility since he was in cruise and above Va [ or Vy ] presumably. The latter , of course , could account for a few break-ups recently in near or in T-storm conditions-Crossfields’ accident comes to mind .

[@fistfullamullah]

Yeah, the PC12, both Legacy and NG are full FIKI spec. Our ops spec/policy was light to moderate icing and light to moderate turbulence. That’s a ton of ice and a rough ride, especially single pilot IFR/IMC at night to minimums, with freezing temps to the surface. We try to avoid ice, but try flying in the PNW or NE of the states in the winter months (which are long). People still need essential services and still need their Amazon prime garbage from China delivered. Yeah, I agree. We can Monday morning coffee this thing to all ends, but where human factors, physiology, environment, capabilities, currency, recency, proficiency and luck come together, the outcome exists.@@davidwhite8633

[@jeffhiner]

The weather at KSLC has been severe enough this winter that I have cancelled several planned flights. That particular day the pilot would have been chasing what became a NWS Winter Storm Warning when it reached here. A PC-12 is a very capable aircraft. But FIKI or not, a whole lot of risk factors stacked up that day. Single pilot IFR, night IFR, single engine, guaranteed icing conditions, and then the turbulence AIRMET... a lot of airlines were delaying flights, and I wouldn't have felt comfortable taking off into that. I wonder what the plan was for assessing climb performance, for turning around, if there even was a plan.

[@jacknisen]

But at least the operation is CAMTS certified.

[@Diax1324]

I was debating even making a drive to the grocery store on the day that this occurred.

[@nappozulp4199]

My home airport is in the smoky mountains, 24A, and have experienced severe mountain wave turbulence twice in the last year in benign VMC day conditions. The scariest experiences I’ve ever had. Totally unexpected, really tossed me around…thought my aircraft was damaged and I was a goner. I can’t imagine what it would be like in night severe IMC.

[@jeffr6280]

The worst turbulence I ever experienced on the airlines was on climb out from Reno. It was the real deal-items hitting the ceiling, minor injury to a crew member etc. Have to question the decision to fly a patient in conditions like this, and also the decision of this company, who has a history of fatal incidents, to continue to fly these high workload missions single pilot.

[@beehappyalways]

Yes, Reno and Las Vegas both have terrible turbulence to fly in and out of.

[@pfsantos007]

Yes, but consider the pressure to take a patient to a more suitable location for treatment. Tragic irony for sure.

[@boneseyyl1060]

@@pfsantos007 There is no pressure to move a patient. Not from a medical standpoint. I flew on many aircraft as part of a medical transport team. Physicians are not stupid people. They are not going to risk a patient or staff or family to move a patient in unsafe conditions. Therefore it is not a medical decision and no pressure would originate from hospitals saying "we have to move this patient". In Canada, Medevac flights are covered and paid for though government insurance. There is no profit motive. We would ask if flying was an option and if the answer was no, we looked at other options or the patient remained until conditions changed. If there was any pressure to fly in this case, it would have come from a privately owned company, whose motive was profit, which probably accounts for having only a single pilot flying in very adverse conditions. You might want to consider this, when voting. Privatized health care puts profit ahead of lives.

[@chrisgraves-pp1ph]

@@boneseyyl1060 My spouse worked for this company and there is pressure to fly. The physicians are so separated from the transport process that risk/benefit doesn’t even occur to them. They are pressured by admin to clear a bed, especially a billable patient. Staff shortages put physicians under pressure to clear beds as well. The company will rarely refuse a flight, and if they do, the job is shopped to the one that will. 3 to go, 1 to no was a BS mantra sung but never followed. If you turned down flights, you got canned. Turnover was high amongst pilots and medical staff, so low experience medical staff rarely questioned PIC. As medical staff became experienced and willing to question flight requests than adverse actions would occur against the employee. I know conditions in that area. Lived there for 47 years. Tower is within 200 yds of the hanger this flight originated, and the taxi way that they missed is 800yds from tower. For pilot to miss taxi way meant conditions were bad, and for tower to give direction was another “watch out”. These conditions are common, and a lot of transports occur under these conditions. “Normalization of deviance” is an absolute factor, but mostly in the pressures to fly. Would it change your mind to know that the ground crew and the flight crew were questioning why an order for transport for a stable patient was being initiated? Because that was occurring. I worked in an adjacent agency to the operator. I know there is pressure to fly. My spouse directly experienced this pressure and experienced numerous mechanical and risk failures in this area. The medic on the flight I worked with on ground. I lost a peer on a flight that shouldn’t have happened, and was questioned by the ground and aircrew for its necessity. Don’t tell me there isn’t pressure. My spouse is alive because they left that service.

[@prawnstar9213]

Yeah Reno and into Palm Springs can get really really REALLY bumpy.

[@toddb930]

Thank you for sharing your thoughts on what possibly happened Richard. I really enjoy listening to your descriptions.

[@lesbouma9666]

He was in an enroute climb segment so pilot work load should have been minimal. It seems control was❤ lost when the A/P disconnected. There have been at least 4 other PC 12 accidents similar to this one. Something as simple as an A/P disconnect caused complete loss of control of the aircraft. Autopilots have gone from accessories meaning luxury items to necessities meaning they can’t fly with out. These accidents prove there is not enough emphasis on basic IFR hands in skills. In the old days Chief Pilots would hardly let you use the auto pilot, these days many discourage hand flying …..and we can see the results.

[@gwyoung3509]

Right on!

[@christinarox24]

Thank you for covering this! I’ve watched hundreds of accident analysis videos but it hits different when you knew the pilot personally.

[@chrisanderson4799]

I’ve been flying the PC12 since 1997, yes, 26 years. It’s a terrific airplane and I would fly it about anywhere. It handles the Ice very well, better than any other Turbo Prop I’ve flown. With that said they recommend not going below 135 knts indicated in icing. I personally use 140 knts as my number but usually try to be between 160 and 145 if at all possible. I’ve never had a issue but error on the side of caution.

[@ricardokowalski1579]

Good info. Thanks.

[@richardmcspadden9189]

Thanks for the insight on speeds.

[@PInk77W1]

Would u have done the flight in question? Thx. I’m not a pilot

[@paulholterhaus7084]

With severe turbulence, That airspeed indicator was probably all over the map, even momentarily dropping below an iced up stall speed......................Paul

[@davidwelsh829]

Would you take off after not being able to find the runway? Heavy icing plus turbulence may exceed anything that you have experienced. Add possible mechanical failure or losing the Stab and nothing you or your 140knots can do.

[@Firestorm637]

Several medevac crashes same company recently, last off Maui. Reno has a great hospital. What was the rush to another hospital in a bad storm, single pilot, and at night. Sad!

[@GabeWil]

Just want to add human factors to this excellent analysis. Get-there-itis may be incredibly powerful when needing to transfer a critically ill patient. I wonder if perhaps some crews push the envelope for this reason. Or perhaps feel they are protected somehow because of the worthwhile mission and cargo. These are often the most incredibly capable and experienced pilots and crews.

[@ghostrider-be9ek]

some outfits wont allow the pilot to know about the patient condition - to avoid just this scenario. But I can tell you that, as a parent (so was the pilot) and the ill passenger was a child, it would be hard to refuse air transport.

[@Milkmans_Son]

That's not how it works. These are not trauma patients, they are hospital to hospital transfers so generally stable enough to travel (and if they weren't, the pilot wouldn't know it). If their condition changes on the ground, they turn around and go right back to where they came from. If it changes in the air the decision tree is no different than any other in flight medical emergency. Anecdotal, but pressure to go was higher with both cargo and private. Helicopters might be different.

[@360nofx]

It was not a child. And policy is most certainly that no patient information other then weight for planning purpose is given until flight acceptance. There should be no consideration of severity in flight acceptance even if this were to be a scene or 911 response. That seems dispassionate but is for just that reason that we want to help and you have to make a solid safe decision about safety not about trying to make it work.

[@GabeWil]

@@Milkmans_Son I don’t doubt that in this incidence you are correct. In general though, when we order transport from our rural area to a regional children’s hospital for patients like an intubated 3-month-old or other critically-ill and at times unstable children and adults (traumas, medical cases, surgical cases like ruptured abdominal aortic aneurysms, and the list goes on and on) there is simply no way that the pilot does not see that critically ill patient being loaded onto his plane. If there is truly a level of separation and detachment, that is admirable and safer for all. As these videos are educational and designed to prevent future incidents, knowing all potential factors is valuable I think. I try to be very careful about ordering air transport for my patients knowing that every year there are a few flight crews that never make it back.

[@Milkmans_Son]

@@GabeWil I'm not saying the pilot doesn't know anything about the patient, I'm saying by the time he knows anything he has already made the decision to fly. At least that's how it works with a different outfit that flies the same airplane type in the same region of the country.

[@WingZeroType]

the level of professionalism and knowledge in these videos is always fantastic to see. Thank you for the efforts you put into making these and helping us all be safer.

[@danielnak2634]

With over 7000 hours on the PC12 predominantly in Aeromedical role, I have never encountered icing conditions that the aircraft wouldn't handle. The system needs to be activated early and will not shed the ice completely. However it will be safe to fly into known Ice. Prop vibration will occur if ice is allowed to build up by pilot. The -45 series autopilot will disengage in moderate turbulence and has to be flown manually, at least till re engagement is possible. Second pilot may have been of assistance however as a single pilot one has to be capable to manage manual flying not just to have a rating to be able to operate in these conditions. My money is on spacial disorientation, followed by exceeding the air frame limitation causing inflight breakup. However, I would prefer to leave the assessment to professional investigations, as I am NOT one.

[@360nofx]

With 7000 hours in Medical aviation, wouldn’t you say that there were just too many risk factors? Ice, visibility, turbulence, night etc. even if the aircraft is “rated” Jesus Christ there is still a limit where you have to say this is crazy! I’m saddened and horrified at the whole system as a medical flight crew member myself that not one of them voiced their inner fear and told that hospital that they had to wait a couple more hours till daylight for safer conditions. It’s a lesson to us all that when it sounds wrong, it’s because it is!

[@jjsemperfi]

The program I work for has a PC-12 that stays incredibly busy during the winter. They rarely decline flights due to snow or icing. I doubt it was an icing issue. My money is still on the pilot having a medical emergency. RIP to all.

[@boneseyyl1060]

You never encounter icing conditions that the aircraft can't handle until you do. You might want to reconsider that philosophy.

[@mortalclown3812]

​@@boneseyyl1060 💯💯

[@et9120]

Interesting, there is another PC12 operator saying the opposite of what you are in the comments. They are saying the FIKI capability is oversold, even when activated early...

[@kevinkirkland8762]

To me, it appears that the accident sequence probably starts back at 05:11:34Z when the aircraft starts the big S turn right then left, which is a deviation from the SID. Pure speculation, but smart money would be on the autopilot disengaging at that point from either sever turbulence, or potentially reaching a trim limit due to icing. Understand that the ADSB altitude data is not 100% reliable, but it turns right and loses a little bit of altitude, gains it back, turns left to get back on course and loses a little altitude before gaining it back. It looks like the pilot probably had his hands full and in those conditions at night, seems like a perfect recipe for spatial disorientation.

[@chrisgraves-pp1ph]

The accident sequence occurs when the PIC misses the turn on to the taxi way and has to be guided by tower to next turn. I know the grounds. Tower is 200 yds from the hanger, and 800 yds from the missed turn. Per a source on the ground crew that transferred flight crew and patient, all were questioning the necessity to fly a stable, low acuity patient during these conditions.

[@timothybuck6860]

I used to fly Medevac out of RNO to SLC in a turboprop, so this one hits close to home. Spent many a night flying in those exact same conditions. Blancoliro paints this one as spacial disorientation, but I'm having a hard time buying that. This airplane had to be equipped with an autopilot to be legal for this 135 single pilot flight, and it appears that the autopilot was functioning for the first part of the flight. Did it fail? Did control forces force it to disconnect? I'm guessing the latter. It strikes me as significant that the airplane rolled into a 90 degree right hand turn at 05:11 and then recovered to parallel the course (but didn't turn back to intercept it again), and then the final spiral was to the right again at 05:13. That tells me that there was some control problem. The airplane wanted to turn hard to the right. What was causing that? Having close to 3,000 hours in turboprops with de-ice boots flying in all kinds of weather, I've had plenty of times when the de-ice boots didn't work properly. Everyone who has flown de-ice boot equipped airplanes knows that you don't cycle the boots until there is a significant buildup of ice, because if the ice is not thick enough it will not break off and will form to the contour of the inflated boot. De-ice boots are finicky! Sometimes they don't inflate well due to an air leak. Sometimes they inflate just fine but the ice sticks to them. Possibly a control problem due to incomplete or asymmetrical de-icing. However, with a temperature at -1C on the ground, if there was a standard lapse rate it would have been way too cold for icing at 18,000 feet. The icing band is rarely more than 3000-4000 feet thick. Lapse rates are never exactly standard, so I'd be looking for PIREPS in the area and icing forecasts for that altitude. So the asymmetrical icing theory is a hard one to swallow too. But I still think that there had to be some kind of control problem that forced the autopilot to disconnect and drove the airplane into a hard right turn. He recovered it the first time, but not the second time. You mentioned the possibility of a stall. The airplane had a ground speed of 164 knots when it started the first right turn off course, and 194 knots when it started the second right turn that ended in the spiral. You mentioned the possibility of the airplane coming apart due to turbulence. I would have a hard time buying that one. Moderate turbulence is very uncomfortable, but not dangerous. It would take VERY severe turbulence (as in a thunderstorm) to cause structural failure. The turbulence could have certainly complicated his control issues. Again I'm wondering if there were any PIREPS on the turbulence at that time? He was climbing through 18,000 when the problems started. Was the pressurization working? That is probably not the issue, because TUC is still about 20-30 minutes at that altitude, but it would be something to consider. If I was an investigator, I'd be looking at the maintenance history on this airplane. Any history of issues with the autopilot? Any history of issues with the de-icing system? Any history of issues with the pressurization system? I'd be looking at PIREPS and icing forecasts. I've done all kinds of flying. Most of my career was in the part 121 world, but I'm currently back in the part 135 world of business jets. But the most stressful flying I ever did was medevac flying. It is often in these kinds of stressful conditions in older equipment and a compelling reason to get the mission accomplished.

[@chrisgraves-pp1ph]

Tim, my guess is you flew with American Medflight, who was bought by REACH, who contract with Careflight to operate in western nevada? I have heard through contacts that ground crew and flight crew were questioning the necessity of the flight with a stable patient that was being transferred for a non -emergent procedure that could have waited until better conditions. Did you experience operational pressures when you flew? Given Blanco’s video and knowing that PIC missed the taxiway due to visibility, needing to be guided by RNO tower to taxiway, do you feel that the flight should have been a “no” by crew and PIC at this point, or was there operational inertia pushing them on? BTW, my spouse worked for this service and AMF. I did orientation for the service, but never flew. Risk wasn’t worth the crappy pay.

[@madelinescafe8573]

Excellent analysis...keep them coming...we pilots can learn so much and prevent future accidents

[@scottw5315]

I'm sitting here as a retired Naval Aviator listening to this and thinking, Night, IMC, Single Pilot, Single Engine, Icing conditions. No CO I knew would have let anyone fly in those conditions.

[@d.t.4523]

Thank you. Good luck! 👍

[@Paul1958R]

Colonel McSpadden Thank you for this report. I am not a pilot but am trying to understand these accidents. This is such a tragedy - trying to save one life and loosing five.

[@easttexan2933]

My understanding of these care flights, that all occupants of the flight must agree on "go" or no-go". That's a good idea, but one has to wonder how much understanding nurses and patients and family members have concerning flight into hazardous conditions. Clearly the PIC believed the aircraft was capable of handling any icing / turbulence conditions encountered. Another pilot just trying to do the right thing in helping someone. This was a terrible risky flight. Deepest condolences to all family members, loved ones and friends.

[@glennmuir5617]

You raise a good point about the passengers' understanding of hazardous conditions when making "go or no-go" decisions. We also should consider the anxiety people may feel about going against the pilot's decision. I've been that guy, the guy that says no and grounds a flight for the day and it wasn't a comfortable position to be in. I won't go into details but I was in a _de facto_ leadership position for a group of technicians using aircraft to access remote backcountry areas for resource-related work. Based on the flights of the previous day, I made the call to not fly. When I said "no" I was immediately under intense scrutiny from the pilot, aircrew, and flight manager who worked for the air service. They all pressured me to change my mind. It was a tense 30 minutes there on the flight line before the rest of the fieldcrew spoke up and backed my decision. While everyone theoretically has the power to say "no", that can be a very steep hill for many folks to climb even when they feel uneasy about the flight.

[@Milkmans_Son]

That policy can't be official.

[@easttexan2933]

@@glennmuir5617 couldn't have said it any better. Hard to count the number of times I elected not to "drive" in hazardous conditions because the risk was too bad. One never knows if one of those decisions to not go turned into a decision to go and a horrible wreck occured because of it. It's sorta the "if a tree falls in the woods" saying. Man's inner being to "not disappoint those around us" is not always the road to follow even if we can.

[@davidwelsh829]

Guardian needs to take a long hard look at their safety program before the FAA does it for them.

[@747-pilot]

@@davidwelsh829 Yes, I’ve heard they have a pretty bad safety record!

[@davidrichter57]

I'm late to this one, but kudos to Richard for a clear and sober analysis based on the few clues available. This series makes me proud to be an AOPA member.

[@garyplewa9277]

If ice was a factor, this accident could be similar to the TBM-700 that came apart and crashed onto Route 287 in Morristown, New Jersey on 12/20/2011 (N731CA NTSB Number: ERA12FA115). Commercial aircraft departing the NYC area were reporting ice build up so fast their equipment could hardly keep up. This was relayed to the TBM pilot, who thought he could climb thru it when he requested a higher altitude. In less than a minute the TBM was falling and breaking apart The last transmission from the pilot was to the effect of "We have...." then nothing. Five people died in that accident.

[@Darkvirgo88xx]

On that accident they found the inertial seperator in the off position so the ingestion of ice in the engine probably contributed to the Morristown crash.

[@ajmomoho]

@@Darkvirgo88xx Well that’s helpful information. So the crash likely wasn’t entirely caused by aerodynamic failure of the lift surfaces.

[@Stephen-Harding]

Yep. I thought of this accident. In barely minutes this highly capable aircraft went from OK? to disaster. Of course the lesson was how fast icing conditions can occur and overwhelm. Also, that an encounter with actual icing should be considered an emergency. I can understand how pilots can find themselves inadvertently in icing, or forced with no choice to proceed through, or ascend through, or descend through known icing. What I cannot understand is why a pilot would choose to intentionally take off into known icing.

[@GabeClendenning]

That’s exactly the accident I was thinking of.

[@Darkvirgo88xx]

@@Stephen-Harding Also that Morristown accident the pilot did check the weather but no one gave him the update that propeller aircraft should be held at a lower altitude due to his planned altitude being above it. The controller asked him to climb and he agreed and confirmed the icing and said its no problem. Then within seconds he said he was getting a little rattle which is believed to be the engine ingesting the ice. Then he said declaring and started dropping like a missile. I watched a video by Pilatus on stall testing and there is a reason they implemented the stall warning and stick shaker. When the system is off it breaks left hard into a violent roll that would explain why they start to drop and come apart because I would assume the startle effect would take a pilot by suprise.

[@hughscot]

Excellent analysis. As a pilot, I can't imagine taking off in those conditions.

[@747-pilot]

Yes! Especially *_SINGLE_* pilot, IFR!!

[@scottw5315]

I'm a retired Naval Aviator and we wouldn't fly in that weather short of a war emergency...

[@W.F.Fischer]

Very, very good explained!! Greetings from old Germany 🇩🇪

[@trevorjustinjones]

The legacy PC12 has a very weak Autopilot that kicks off with even a modest amount of turbulence. I suspect the ice was a minimal factor. I suspect the turbulence kicked the AP off and then the pilot experienced spatial disorientation.

[@crazyralph6386]

Good theory

[@greglee101]

Wave and rotor. I live south of Reno and noticed wave and rotor conditions to the east Friday during the day. If the wave was high, say 15 to 20 thousand feet, the altitude seems about right for rotor. Rotors, typically below the wave (lenticular) have torn many airplanes apart. Vertical wind sheer with speeds over 70 miles per hour have been documented. In the late 1950’s and early 1960’s the government commissioned a group of sailplane pilots to take wind speed and direction measurements to better understand the dynamics of lenticular clouds and the accompanying air turbulence. One of the test gliders was ripped into multiple pieces. As I recall (from reading) the engineering team estimated the glider experienced over 20g’s. That was about 100 miles south of where the plane went down. So flying in and around wave conditions has the potential for high force turbulence which could easily take a stabilizer or with tip off. Just another thing to consider.

[@jayrenner1053]

Yup. My Dad thought he was inverted when flying a DC9 one night - he pushed the yoke forward the plane slowed down. Pull back, it sped up. The co-pilot had to take over while my Dad's senses finally got back to normal and he realized that they were in a extremely wide and violent updraft.

[@gwyoung3509]

Great point that no one has mentioned! Rotors terrify me!

[@Dmitriy_Suslakov]

Thanks,, very useful for safe flights

[@billjamison2877]

My sincere condolences' and prayers to the families of these lost souls.

[@darkenedskiesahead3670]

Without knowing the conclusive outcome of this investigation... (IMO) when functioning as a commercial air transport provider, any operations into known significant or unusual parameter(s) should require a full crew. Two seats, two pilots, two heads... no cost cutting during any elevated risk condition(s).

[@747-pilot]

EXACTLY!! It is, frankly, beyond stupid to allow these types of operations (especially in conditions such as these) to be flown single pilot!!

[@joelcheek3494]

A company I used to work for once had a KingAir that we used regularly. The CEO reminded us one day to "never get on that plane unless there are two pilots". He later said he was too young to die in a plane crash.

[@josephdale69]

Yeah. I’ve been at a major airlines for 30 years. Before that, I had the option to fly single pilot delivering mail. I talked to a few pilots who said they’ve been scared flying. I declined the job. And those were the days when you needed 5000 hours to do that. Nowadays, anyone with the time or experience isn’t doing this job.

[@Webleys]

@@josephdale69 I've got more than 8,000 hours in a FedEx Caravan, almost all of it in the booted version and 9 years of that in the ice factory around the great lakes. That operation is all single pilot in a considerably less ice capable aircraft and mostly at night. Luckily the companies almost always cancelled before we got a chance to. That said we probably only got cancelled2 to 4 times per year. You have to be really on top of your game to do it 5 days a week in virtually any weather and the learning curve for somebody coming to it from a Cessna 182 is steep, and hopefully in the summer so you have some time to gain the experience and get your first ice encounters in the fall when you can, at least, descend to get out of it. Add mountain west altitude and turbulence and it can be overwhelming. We had a steep learning curve with the Caravan in the early years and they learned not to fly Gunnison to Denver and such routes and switched to F27s and later ATRs on those routes.

[@daveblevins]

I was on a flight as a student pilot with my instructor one night, in Illinois. I was invited by him as I had about 35/40 hrs working on my private certificate. We were in a piper Lance (1974), and enroute to Wisconsin to pick up our in-house DE who had ferried a 421 to the area. I remember asking my instructor what the turbulence limit was on our plane because it was all over the place. Chicago center had told us that a DC -9 had reported moderate to severe turbulence in our area. 🤯 I remember the Jepps binders hitting the roof many times, and that's why I asked. Bam !! 💥

[@petebaranko5468]

On this version of the PC-12, if Pilots do not perform a pre-departure cycling of the de-ice boots they can "lock out" and not cycle in flight. Often the air in the de-ice system contains moisture. This moisture if the system is NOT tested before departure can freeze causing the loss of use of the de-ice system on the wings and tail. Of course Pilatus and most operators do not require the system to be tested, this advice is solely the result of operating in icing and identifying how to prevent the deice system lock out.

[@gerhardcombrinck7026]

Good video- thank you.

[@dutchflats]

Very challenging conditions for any GA aircraft indeed, even a transport category aircraft would be having a rough ride through that. Pilots have to be very professional in their approach when operating these kinds of high performance single engine airplanes in such conditions. Critical to keep IMC proficiency and systems knowledge at a peak, these are your grandad's SEL planes!

[@MichaelM-to4sg]

You failed to discuss key point in adsb data. Pilot climbed out of RNO along SID. The tracking would support he engaged APU. Approximately 10 minutes into flight he abruptly deviates from SID turning south for just under a minute without any change in elevation. He then turns left, easterly, as if to again follow SID. This suggests to me the APU was disengaged, either by APU or pilot. My guess, which is all it is at this point, is APU was disengaged by aircraft due to severe turbulence. It should be noted in communication w/ATC on ground, he is warned of severe turbulence at all flight levels which he acknowledges but does not inquire about possible workaround or alternate headings to mitigate turbulent air enroute. Once he has turned east again, he does climb for 2 minutes, he also has one communication w/ATC which is not stressful sounding but his responses are slow. There’s also an earlier communication where ATC tried reaching him 3 times before he responded. All are indications pilot was flying behind the aircraft. The fact he was still climbing just prior to the eventual spiral suggests it wasn’t an icing situation. His fairly aggressive climb just prior to spiral further suggests a stall and spatial disorientation. I think what we’ll learn is pilot was in over his head from the ground. Why a Part 135 flight in IMC is flying without a pilot in right seat is irresponsible. This air ambulance has had 4 major events in last 2 years, 3 involving fatalities and loss of aircraft. The Hawaii crash is a concurrent investigation. At some point NTSB needs a long look at this carriers operations

[@Darkvirgo88xx]

Everyone should go listen to the security camera audio of this crash. It came down fast. The engine begins to scream as the rpms rise then you can hear the prop depart the airplane as its breaking up.

[@MeaHeaR]

Probable Cause Summary: 3:08 Icing 4:09 Pilot Agressive Maneuver 4:47 Turbulence 5:14 Spatial Disorientation

[@Freq412]

I fly (flew) helicopters and know what it's like to be asked to fly in bad conditions. The feeling of dread is something you won't soon forget. I managed to get through it without an incident or accident (I thank my lucky stars). With all I've heard, I'm glad that I never got involved in EMS where you are compelled by concerns for saving the patient. The guidelines for go/no go just don't seem to be solid enough.

[@Nervegas]

I was a flight medic/flight safety officer for almost a decade, we had strict go/no-go guidelines, and ultimately the PIC had final say whether to accept a flight or not. They also gave us zero patient information until we were already in flight. I worked in texas where our weather can be extremely unpredictable and even with IFR and NVG capability we turned down a lot of flights for safety.

[@JimBronson]

So true. Medical flights have a really bad safety record.

[@phuclam6704]

😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅😅

[@user-wz2qe2pv6r]

Over in the UK in bad weather, medivac is grounded whatever the situation.

[@Ethan-jo1wf]

I know I just recently did some single pilot IFR in a much lower performance aircraft and in much less harsh conditions and even that was demanding, can easily see how in those really rough conditions something could turn bad quickly.

[@Flying_fisher]

Flown this plane a lot. Used to work for Guardian out of Elko, Ely and Reno. Great aircraft, great company. Knew the med crew well. Hit pretty close to home.

[@Firestorm637]

That initial turn to right then correcting on course, autopilot clicked off secondary to turbulence then control of airplane then disorientation then right spiral exceeding airframe strength

[@nonmihiseddeo4181]

Wow, hard pass on driving in those conditions, let alone flying. EDIT: Rime can accumulate instantaneously, and the conditions were hazardous in the extreme. Talk about "writing checks your body can't cash!" This is a pilot-error crash, and the error was agreeing to fly. Full stop. Thanks for another great video.

[@tt9875]

Very sad.. They should have never departed. Has to be other hospital options, ground ambulance options, something.. That flight should not have happened.

[@sey1yes2]

From what I've heard is that this flight presented risks that cumulatively put the probabilities of difficulties very close to if not exceeding the absolute limits of safety. What this analysis may not account for is reduced ability to "think outside the box" that all professionals develop. In short, they become accustomed to risk and might not realize that when operating close to the limits of multiple domains of risk, cumulatively is actually exceeding the limits. I'll be looking forward to what the NTSB's ulitmate conclusions are. In the meantime, perhaps operators might re-evaluate go/no-go criteria.

[@petebaranko5468]

This PC-12 had the older big wing tips. These had a tendency to build up a lot of ice and were NOT protected or able to shed ice once ice built up on them. Climing at a higher than normal climb speed was needed, but with the increased drag climb rates could drop extending your time in the icing. Compounded by a locked out de-ice system and you have bad combination that can surprise the pilot.

[@davidwhite8633]

Did this model have de- ice on the tail horizontal stabilizer ? Just curious.

[@petebaranko5468]

@@davidwhite8633 yes, all PC-12’s have “Known-Ice” and full wing and tail protection.

[@leighhuff5806]

Another great incitful analysis by Richard. We don't see many accidents like this that start at FL190. I would have thought that the plane was beyond the danger zone at that point.

[@maesc2001]

Never been in favor of single pilot IFR into real low or turbulent and/or icing and thunderstorms especially. Lost a very competent friend in the mountains to such conditions.

[@GrooveTasticThang]

Let’s not forget the mountainous terrain. With icing degrading the aircraft performing the ably to descend to regain density and temperature was limited because the MSA was probably above FL140. There were strong jet streams that day from LA to DEN so wave or rotor turbulence could also have overcome the aircraft performance margins. Not a nice situation to find yourself in. Turning back may be an option .

[@caliboy7654]

2 pilots needed for this flight. Beautifully capable and complex aircraft. AP may have disengaged due to turbulence, icing, etc. Task saturation, spatial disorientation in a heartbeat. Ideally, Pilot 1 aviates, Pilot 2 troubleshoots & navigates. We can all learn from this. Very sad loss of lives. Sincere condolences to the families.

[@Mjr._Kong]

Very much agree.

[@747-pilot]

It actually SHOCKS me that they even allow such operations, in conditions such as these, to be a *_SINGLE_* pilot affair!! But then again I’ve heard that this company “Guardian” has a pretty bad safety record. So maybe it’s not that surprising after all?

[@mmayes9466]

@@747-pilot who is “they?” Referencing the party that is “allowing” this?

[@thedukeofbork3147]

@@mmayes9466 The answer to your question is probably in @747-pilot's second paragraph...

[@wintercame]

I think the patient was headed to Salt Lake for a liver transplant. How terrifying those deaths must have been. Rest in peace now, all aboard.

[@bigbass421]

I live about a mile from the south end of Runway 34 L at KRNO. I've seen that airplane come and go out of the airport many times. I've seen it parked over at Atlantic Aviation, as well. Made me sad to learn of this. What makes me shake my head, is the fact that we have FULLY equipped hospitals here, and a BRAND NEW Northern Nevada Medical Center hospital just south of the airport on Longley Lane, not more a mile from the end of 34L WHY were they flying a patient to Salt Lake City? What do they have there that made this obviously risky flight necessary? May the victims Rest In Peace.

[@qiliu88]

Could it be that it is medical insurance related? For example, if the benefit for out of state coverage is only for 7 days or until stabilized, there would be a financial pressure to move the patient back to home town?

[@larryegilman1]

Or there was an organ that matched the pt awaiting in salt lake, or who knows? Tragic outcome

[@Darkvirgo88xx]

In the ATC audio the conditions were so bad he couldn't properly taxi to take off because of the horrible visibility ATC had to guide him and it resulted in him having to do the process again to finally take off.

[@VLove-CFII]

This should have been a small clue to this overconfident pilot.

[@alpenglow1235]

One-quarter inch of snow would be enough to obscure taxiway markings. This is not a factoe contributing to this accident.

[@stevenflattum156]

Too cold at 20,000 ft to have lots of ice. I believe that it was severe turbulence then autopilot disconnect. Then over G or spatial disorientation.

[@YahushasDisciple]

It sounded as though he was way over speed, causing the breakup of the plane. Single pilot at night, could be spatial awareness issues or icing of the pito tube leading him to believe that he was way under speed. The audio from a local security camera captured the sound of the plane and he was very high speed upon impact.

[@zabamaz103]

There’s an audio from a security camera (just audio) near this accident and you can clearly hear the aircraft spinning before it hits the ground.

[@adam1885282]

Been waiting on this one, went down less than 30 miles from my house

[@ezramoses4651]

He stalled it and the startle effect caused him to rip the horizontal stabilizer off. Flying slow in icing conditions is deadly

[@lawrenceralph7481]

I would never want to be in a aircraft flying into a storm. Not private, not commercial. I hope pilots give their passengers a choice, a clear briefing on the risks and the option of opting out

[@foryst]

The older PC12s would kick off the autopilot whenever you got into rough air. I wonder if the autopilot turned off without the pilot realizing it?

[@desmodromic4586]

The AP did turn off for sure, and that’s where trouble started in IMC at night single pilot

[@shanewise4669]

PC-12 Climb into icing speed 135kts with de-ice working , 140kts with pneumatic boot fail, indicated speeds

[@kenclark9888]

He was having issues on taxi out as well. He went past the taxiway centerline and had to come back. That was a bad night out there. I live about 6 miles west of the crash site. 737s were calling moderate turbulence that night. We can Monday morning quarterback anything, as for me I’d waited to the next day. The patient was not critical

[@ElCapitan12]

The B engine on the legacy PC12 has lower power, I think around 20% lower than the NG, with a full load, open separator and ice equipment on, he probably was working hard. If he was in moderate turbulence, it’s harder with the small original AI to hold it all together. Sad deal. I had my autopilot kick out in an NG 2 weeks earlier at FL290 in TX in moderate to Serv turbulence, I can tell you it was not a good time, I pulled the power back and was able to turn East to use 140 knot X-wind to get away from the system. I could barely see my 12” display things where shaking so bad and it was a good workout making a 90 course change in that environment.

[@geoffedmonds6507]

I often wonder why these flights are made in the first place? Why just a single pilot in such demanding situations? Night. IMC, Snow, Icing conditions, Bad visibility, Turbulence. Just seems hinky in the first place. What was the pilots experience? Sad all the way around.

[@jagboy69]

Medevac missions are brutal. RIP Airmen!

[@p38cobra]

Icing most frequent common denominator in this kind of accident; very tragic

[@TheRockerxx69]

Remember the Pilatus that went down in Milan ltaly, two years ago (?) Just after take off. Can u track that accident?

[@Bill_Woo]

Best logical, scientific first look yet at this incident. Others seem to be falling over themselves with A. Low vis B. L.O.C. C. Ergo spatial Dis. But I'm surprised you didn't also mention physical. Even if there's no specific support, it actually fits the facts better than any of the other speculations. Consider: sudden deviation (unconscious or blacked out , falls onto the control). Sudden loss of communication(blacked out). Spiral in one direction(blacked out, falls onto the control). Massive, MASSIVE plummet(unconscious or blacked out...). Just saying, it fits too well to ignore.

[@Bill_Woo]

The descent fpm was so huge that it also should be strongly considered as what did the in air breakup.

[@decapitatespammers]

Sounds like you know that Sherlock Holmes quote. Yes, other factors like weather and visibility are suspicious culprits, but that's no reason to ignore the "easy" explanation, a less exotic possibility. And oh, I just read 30K ft/m. 30K !! Is there any craft that can survive that intact?

[@kenclark9888]

That no one knows. Maybe he was busy trying to recover the aircraft to talk

[@UncleKennysPlace]

@@decapitatespammers That's actually just under 300 kts, so a lot of aircraft could technically survive it, but you'd have to start out very, very high, and begin recovery very, very early. Because you'd be in a dive. Then again, ADS-B altitude information is sometimes sketchy.

[@loudidier3891]

Except that it appears he corrected for the first turn off course then less than a minute later turned the same way. So Spatial disorientation, caught it, looked away from flight director, possibly to check for ice on wings since you have to make sure the correct amount has built up before popping the boots, and since his inner ear was still sending wrong information to his brain didn't catch the new turn soon enough.

[@topofthegreen]

Im surprised a PC 12 came apart like that.

[@triedproven9908]

It's very easy to exceede the design parameters when overspeeding and at a loss of control.

[@bw162]

The United near crash after TO from HNL exceeded the 2.7g that requires extensive examination of the airframe.

[@topofthegreen]

maybe a 2 man crew could have prevented this, it sounds like the pilot was task-saturated.

[@tmaschm]

Please do the Piper jetprop Accident In Texas?

[@desmodromic4586]

Normally this plane is n AP throughout the SID and the ads b data seems to confirm this, for some reason the AP must have come off, then things can get hairy pretty quickly in night IMC single pilot. Spatial desirientation will play a role but only after the AP has come off, so the question is what made the AP disconnect ä? My guess, severe icing on control surfaces

[@kray97]

I think the part of the tail that broke off (due to turbulence) was the malfunction and the cause.

[@pfsantos007]

Flight recorders should be pretty much on everything by now.

[@stephenp448]

A number of years ago, there was an accident involving a aircraft in the MD-80 family, where the use of de-icing (or anti-icing) equipment reduced the amount of thrust available to maintain the plane's altitude, resulting in a stall and subsequent crash. I understand completely that the PC-12 is an entirely different aircraft with a different type of powerplant and de-icing equipment, but could the use of de-icing have impacted its ability to climb any higher?

[@Codehead3]

It looks like a graveyard spiral…

[@BPJJohn]

Is there a Flight Data Recorder available on the Pilatus?

[@Max50ww]

Would it have been inappropriate for the PIC to require a SIC in high workload flights such as this?

[@artswri]

Another cautionary tale. Very qualified pilot. Wasn't enough

[@jaycahow4667]

From watching multiple videos it looks spacial disorientation happened here. Look at how clean the flying is early in the flight. Looks like the auto pilot was doing its job but at some point it went off maybe due to turbulence and the suddenly they are flying manual in terrible conditions. They finally get SD and spiral downward with G forces ripping the plane apart.

[@DJ99777]

The fact you guys have a town called stage coach is super cute.

[@saabpoppa]

SIGMET for moderate icing doesn't mean you're "taking off in moderate icing" or that the pilot was "in icing condition". You might encounter some, or none. If the pilot did encounter moderate icing, however, that would be very worrisome in a single-pilot PC-12. I flew the crew-served SAAB 340B+ and operated routinely in mod icing; that aircraft is fully capable of handling that, but few other FIKI aircraft are. Not addressed is whether the pilot took off with some kind of frozen precip on the wings and control surfaces. Even if type I was applied, it has no holdover time.

[@Chrismarquez7]

It almost seems like the pilot lost consciousness during the flight. When listening to the tower communication, The pilot stopped responding just prior to the steep right turn. If there were any mechanical issues, structural or icing, I would think he would’ve called for a mayday.

[@ayork84]

That's highly unlikely... pilots are taught to aviate, navigate, and communicate, in that order. Additionally, under high stress situations, a vocal response is usually the first thing to go (i.e. people clam up when stressed). Finally, at FL180 (18,000 feet), a rapid decompression would result in 10-15 minutes of useful consciousness according to the FAA.

[@sixwillwin]

Fly first. Communication is later if possible. Fly. Navigate. Communicate In that order.

[@cogitoergospud1]

Aviate. Navigate. Then, time and workload permitting, Communicate.

[@pjstew]

It's typically the opposite. When things start going sideways the higher brain functions like speech get pushed aside, unless you have been trained and conditioned to do otherwise.

[@BobThePilotN4WFH]

During the eighties I've flown various aircraft, as a single pilot, including 800 hrs of Air Ambulance flights in a PA60 all over the eastern U.S. in all types of weather remaining within the capabilities of myself and the aircraft. Afterwhich I flew the Beech 18 single pilot on a service contract in Georgia. Then moved into a KingAir 200 as a two pilot Captain crew. I have over 4k PIC hours and to me this flight was nothing but an enjoyable and challenging IMC flying well within the capabilities of the aircraft and commercial pilot. IMO: Now I have made this mistake before, At the end of my flying career and something I despise doing, is to fly an unfamiliar aircraft. I was ferrying Mooney's from around the eastern U.S. to San Antonio, TX. I was giving a TLS and thought this was going to be cool flying high in an unpressurized aircraft. Being not one with the aircraft I didn't catch the o2 wasn't working and about 19k feet I accepted the fact that something was amiss. Tracked it down to the inline indicator and it was red. Emergency descent followed by mental calculations to keep the brain thinking. I was lucking. It would appear to me that the pilot was hand flying, passed out and regained consciousness too late to recover. Based on the following, Departs with a heavy load into IMC and icing conditions. He's having to climb at a faster climb speed to remain above the minimum airspeed for icing conditions while having to employ engine anti ice vanes which reduce engine performance. This makes for slow climb and not recognizing the aircraft isn't pressurizing. Why isn't the aircraft pressurizing? Possibly the outflow safety valve is stuck open or won't close because the landing gear fully extended switch isn't triggered. Every pilot should strive to become one with the aircraft. If there is something that can be done from the cockpit you should be ready to do it. Situation awareness is to continuously evaluate your and your aircrafts capabilities and apply this to the environment at that moment. As a single pilot, if a non immediate action emergency was to arise, I would engage the autopilot to reduce the workload and figure out a solution. The Century IV autopilot in the PA60 and I were best buddies. Those Air Ambulance flights are in the logbook between 500 and 1300 total flight hours. I've accumulated 4k PIC over the years.

[@DOOMERdotEXE]

Shoutout to Ed Harris for presenting this video

[@connielentz1114]

As a retired doctor and low hours private pilot. my question is why was the patient being transferred and was it medically necessary to fly in such marginal weather conditions. Although I have called for medieval flights a handful of times it has never been absolutely necessary in my geographically small state of Massachusetts . Given HIPPA rues around patient privacy we will likely never no why the flight was undertaken.

[@rbrosz]

'medieval flights' I'm picturing my doctor telling me they are going to load me into a trebuchet.

[@connielentz1114]

@@rbrosz A trebuchet might have been safer

[@davidwhite8633]

Ditto . ‘No’ ‘Know’. ?

[@atubebuff]

The stall scenario given the conditions is all very plausible but what strikes me is the structural failures. The wing tip in particular.

[@decapitatespammers]

I just read that the descent rate was 30 thou feet per minute, if that's telling.

[@barbaradavis393]

I also would like to understand that. However, the wing failure is really insignificant. Once you lose the horizontal, you have no recourse. The high descent rate will do that.

[@rodneywallace2984]

Right wing tip is where the radome sits... Maybe extra force on that tip

[@romantic340]

A sad and tragic ending , and it it doesn't seem like it was that long ago, the medical Leer Jet going down, doing a unique approach at night in weather, at any rate, hope they figure it out and learn from it, so it doesn't happen again.

[@hankramos8663]

Multiple factors may indeed have contributed to the tragic mishap.

[@davewitter6565]

I would think above 10,000 you would have the autopilot on. Climb on profile at turbulence penetration speed. I assume the deicing system comes at slight performance cost. If the autopilot disconnects due to turbulence at night in weather with a compromised overwhelmed moderate or greater icing situation and possible structure failure that's no bueno .

[@davidcamacho7641]

What about the autopilot masking an underlying condition due to icing and then disconnecting due to force overload and putting the aircraft in an unusual attitude?

[@igclapp]

Possible. In fact the manual warns about this.

[@stevemadak6255]

I'm not a pilot. hey answer me this; Is it a thing to use your autopilot to help you stabilize a plane when you are in bad weather? Or when you get disoriented is it too late?

[@mmayes9466]

The autopilot is used to reduce pilot workload. It has limitations on its use, I.e., it may not be available for use all the time on every flight.

[@wmdjohnson]

These events took place not very far from my home here in Stagecoach, NV. External pressures, enemy number one. Weather, mountains and nighttime flight are enemies 2, 3 & 4. RIP to all on board that fateful night. The pilot gave his life trying to help others.

[@otiebrown9999]

Stall / spin, is a violent event. My first experience was, What the hell happened. Only Aerobatic training makes you comfortable with it.

[@loudidier3891]

Looks more like a spiral on the flight track.

[@bw162]

Under these conditions, your aerobatic training in CAVU conditions isn’t worth much at all. Try doing a loop with spacial disorientation at night, IMC and heavy turbulence.

[@flymachine]

Turbulence breaking up a PC-12? Thats as likely as "a megaladon sank the ferry" I like your methodical breakdown of possibilities though as a learning opportunity - for my money spatial d deterioting into a spiral resulting in a breakup in flight and snap flatspin RIP

[@lobedwonder]

spacial disorientation is not a problem if the autopilot is doing its job.the pitot tube could have iced up also if he forgot the heat.

[@loudidier3891]

Autopilots in this size plane disengage (basically turn off) in turbulence as the airplane bounces around too fast for them to keep up. You can reengage them but they just disengage again.

[@rustusandroid]

Certification for flying into known icing conditions doesn't mean ALL icing conditions. There are many NTSB reports for aircraft that have been lost due to over confident pilots getting overwhelmed with ice in a plane that was certified for known icing conditions.

[@AJdet-2]

Under the circumstances.. I'm going to assume the "go or no-go" was heavily influenced by the medical condition of the patient being transferred. I lived in Sparks for 10 years flew out of reno-stead airport where my Mooney was moored.. From November to April, I never even thought about unlocking the hanger except to check on Molly.. The Tahoe Reno-Sparks area reminded me of a high-elevation Chicago. Probably one of the most turbulent scenarios for general aviation would be flying from Reno to Utah with even a moderate cold front.

[@johnsalem7765]

Where did you get “moderate icing”?

[@foryst]

My thoughts too! There wasn’t moderate icing. I flew a PC12 through that same area about 4 hours before and had trace rime then light clear while flying an approach into RNO

[@davidwelsh829]

Maybe because it was snowing so hard they couldn't find the runway.

[@johnsalem7765]

At FL190 I doubt there could be icing conditions. It’s a shame none the less, may they RIP

[@foryst]

@@johnsalem7765 totally agree. My suspicion is maybe the autopilot kicked off. I used to fly the older /45s and remember whenever you got into rough it would switch off. Maybe he didn’t realize this and the plane slowly started diving to the right? Super sad. My dad passed away in a crop dusting accident so I can only imagine what the families are going through

[@edwardthayer9386]

👑

[@leilanirocks]

Wondering if the condition of the patient possibly needing critical care factors into go/no go in medical flights? It probably should not… but I wonder.