It's July 3rd, 2021, and two pilotsÂ
are preparing to depart Aspen,  Colorado in a Beechcraft Bonanza G36. The timeÂ
is approximately 6:20 pm Mountain Daylight Time.  Their trip began in California early this morning.Â
One of the pilots has recently purchased the  Bonanza, N36JJ, and intends to fly it home to NewÂ
York. The other passenger, also from New York,  has joined the flight as a safety pilot. After aÂ
five-hour and 20-minute flight from Napa County  Airport, the two pilots landed in Aspen around 2pmÂ
for lunch and fuel. Their next stop is Des Moines,  Iowa, and they've waited a little over fourÂ
hours in Aspen before returning to the airplane.  Perhaps the long delay included time to wait forÂ
cooler temperatures and a more favorable density  altitude. But the temperature now at 6:20pm is 77Â
degrees Fahrenheit, and the density altitude is  close to 10,500 feet - not much of an improvementÂ
from earlier this afternoon. Although the Bonanza  G36 is an excellent platform for a trip across theÂ
country - sturdy and spacious, with a Garmin G1000Â Â and an IO-550 with 300 horsepower at seaÂ
level - the engine is not turbocharged.  The Aspen airport sits at 7,838 feet MSL - anÂ
elevation already challenging by most standards.  Given the current density altitude of 10,500Â
feet, the normally-aspirated IO-550 can achieve no  more than about 200 horsepower under the best ofÂ
circumstances - and the G36 is a heavy airplane.  Density altitude can pose significantÂ
challenges in Colorado, which has the  highest average elevation of any state, and theÂ
highest average airport elevation. Every year,  the state is among the top in the nation inÂ
density altitude-related aviation accidents.  As the Bonanza waits to depart, theÂ
ground controller issues an IFR clearance. It's 6:24pm when the Bonanza departs. The pilotÂ
advises that they will make a right turn following  takeoff and requests permission to climb upÂ
to altitude while circling over the airport.  Perhaps the pilots cannot acceptÂ
the IFR clearance of 16,000Â Â feet because they do not haveÂ
supplemental oxygen on board,  or maybe they understand just how difficult itÂ
will be to coax the airplane up to that altitude. The pilot's reference to the southeast departureÂ
is possibly referring to Independence Pass. Their  plan is to eventually cross the imposingÂ
Sawatch mountain range to the east,  with peaks topping 14,000 feet. About 10 minutes later, N36JJ has completedÂ
two ascending circuits over the Aspen airport,  and has reached 10,000 feet MSL. The pilotsÂ
decide they have enough distance to climb on route  and clear the mountain range to the east. They areÂ
perhaps unaware of the recommended mountain flying  technique of climbing to ridge-crossingÂ
height before turning toward the ridge. It's unclear if the pilots had originally intendedÂ
to take Independence Pass. They are now heading  toward an adjacent pass known as Hunter CreekÂ
Valley. This valley will ultimately lead them  to Midway Pass, which is approximately 11,800Â
feet. The Bonanza makes its way up the valley.  Its rate of climb is minimal, averaging aboutÂ
200 feet per minute - about half the climb rate  predicted by the Pilot's Operating Handbook underÂ
these conditions. Still, the high mountain ridges  in the distance are miles away - surely far enoughÂ
to continue climbing and eventually clear them.  The valley curves to the southeast,Â
and the Bonanza follows its path.  The valley floor begins to creep higher, but theÂ
airplane maintains its sluggish rate of climb.  The Bonanza is approaching a semi-circularÂ
mountain ridgeline, with tops over 13,000 feet.  Midway Pass provides a route through thisÂ
ridgeline at 11,800 feet, but at this point, the  Bonanza's altitude is only 10,700 feet. To makeÂ
matters worse, the canyon is becoming narrower.  The pilot has positioned the Bonanza in the centerÂ
of the valley, where the terrain elevation is  lower, but in doing so he has not allowed theÂ
airplane sufficient room for a 180-degree turn.  Best practice for canyon flying is to favorÂ
one side of a canyon based on winds or traffic,  and to allow for maximum turning roomÂ
in the event a turnaround is necessary.  Now, time is running out. It's clear that theÂ
Bonanza won't clear the ridgeline in the distance,  and the valley floor creeps higherÂ
still. The pilots make the decision  to abort - to turn around and escape backÂ
down the canyon. But it's too late. With  insufficient room to make a full turn back,Â
the Bonanza impacts terrain at 11,000 feet. It's difficult to comprehend the impact thatÂ
density altitude has on aircraft performance  without experiencing it firsthand,Â
especially for those who are used to  flying over lower and flatter terrain - asÂ
was the case for these pilots from New York.  The safety pilot held an ATPÂ
rating and was highly experienced,  but we don't know to what extent he had experienceÂ
in flying a normally-aspirated piston airplane in  high density altitude conditions among some of theÂ
highest mountains on the continent. The effects  of high density altitude were evident in theÂ
Bonanza's poor climb performance, and continued  to worsen in the minutes leading up to the crashÂ
as the pilots attempted to gain more altitude.  Precise mixture management is especially crucialÂ
at high altitudes in order to obtain the maximum  performance from an engine. We don't know for sureÂ
if the mixture was properly leaned at takeoff,  and if the pilots continued to lean forÂ
optimum engine power during the flight,  but it could have significantly affected the climbÂ
rate. The ADS-B data indicates that it took three  minutes to climb from 8,000 to 9,000 feet andÂ
four minutes to climb from 9,000 to 10,000 feet.  Given the 10-mile distance to Midway Pass,Â
and the altitude they would need to clear it,  the pilots would have needed three toÂ
four additional minutes of climbing  in their orbit to have a chance of making it.Â
The pilot's assessment that after a couple of  circuits they had enough aircraft performance toÂ
fly up and over the unknown canyon, was at best,  a guess. It's also difficult to recognize how fastÂ
benign-looking terrain is rising. Pilots focus on  the big ridges ahead, but it's seldom those thatÂ
kill. It's the gradually rising valley floor that  catches pilots by surprise. Paying more attentionÂ
to the high ridges in front, pilots often wait too  long to make the turn back. The floor has risen,Â
taking away any vertical turning room. The canyon  has narrowed, limiting horizontal turning room. AtÂ
high density altitudes, ground speed is greater,  making for a larger turn radius. Pilots needÂ
more room for a 180-degree turn than they are  used to at sea level. Exacerbating the problem,Â
airspeed bleeds off in a turn faster at high  density altitudes. A coordinated turn in suchÂ
circumstances is essential, yet the pilots were  likely contending with the urge to pull the noseÂ
around quickly to avoid the approaching terrain.  Finally, there are almost always up or downÂ
drafts to contend with in the mountains.  In this case, the winds were fromÂ
the east at approximately 15 knots.  Approaching the ridge from the west, theÂ
leeward side, the pilots would likely have  been dealing with a slight downdraft - furtherÂ
eroding their already poor climb performance.  The combined result of these factors wasÂ
the impact with terrain at 6:38pm - fourteen  minutes after takeoff. Force of impactÂ
increases by the square of the speed.  Increased density altitude results in higherÂ
ground speed for a given indicated airspeed.  The final density altitude consequenceÂ
levied on the two friends would be a higher  ground speed at ground impact - and a moreÂ
destructive crash. Neither pilot survived. Density altitude affects every airplane. We areÂ
all taught about it, but it's an abstract concept  until we see it for ourselves and experienceÂ
the degraded aircraft performance in context.  Out of their element, theÂ
flatland pilots in this tragedy  linked several critical decisionsÂ
together. They took off after 6pm,  likely believing at that time of day the densityÂ
altitude would have been manageable. They guessed  that after two circuits they had climbed highÂ
enough to handle the mountain ridges ahead.  They didn't anticipate the potential effects ofÂ
sinkers, which are the downdrafts coming over  the mountains in front of them. Finally, theyÂ
waited too long in their decision to turn back.  Density altitude is a stealthy killer. You don'tÂ
realize it has you trapped until it's too late. Thanks for watching this video.Â
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and support us, join AOPA now at aopa.org
As someone that has his majority of time flying in Florida, where there is barely a hill this terrifies me.
I used to own a G36. Great plane, way too heavy. I bought it after finishing my IFR and the salesman told me I could fly it to high altitude airports (think KTEX). I did one time in the winter, near gross weight. Terrible idea, miserable experience. I can easily see myself falling into a similar situation when I first got my ticket.
From the audio it appears they really had no plan once they took off. The fact they filed IFR and were surprised by the 16k assigned altitude speaks volumes about their level of preparation. Sad story, predictable outcome.
While high DA was present here, the complete lack of planning and preflight preparation was what really got them in trouble. Experienced pilots in a capable airplane but without the proper planning it's still not enough. They had no idea what route they were going to take though terrain that is incredibly unforgiving of going the wrong way or being unaware of the topography. Really unfortunate.
This is the kind of thing I worry about as my GA experience increases. These pilots failed to recognize the difference between a simple $100 hamburger flight, which at their experience level likely works out with abbreviated preparation, and a flight needing a lot more careful thought. Things like a FRAT (flight risk assessment tool) might have helped.
They also might have felt time pressure trying to get out of the mountains before dark but also wanting to wait for cooler Temps. Flying GA in the mountains is a lot nicer in the morning.
This video is just crazy to me. Perfect example of CFIT. Perfectly good airplane flown right into a mountain.
Watch your density altitude people. Don’t make guesses. Plan accordingly. Get mountain flying training. My club required it to land at airports above 4k MSL.
I’ve flown into Aspen many times in a Lear and even though it’s a jet, we still needed to take careful consideration of the DA and our weight. Especially during summer. Sometimes we literally couldn’t go. Bare in mind that I would regularly see the VSI of the Lear 60 at 5-6k FPM off the runway when under normal conditions.
ASI always puts out great videos.
I routinely fly in these mountains. You don’t go that way out of Aspen in the summer. You go to the northwest until Glenwood Springs then turn to the east and cross at Rollins pass. You also don’t fly IFR in the mountains in a single engine.
Maybe there should be a high density altitude endorsement.
Doesn’t seem like he leaned the mixture. 300HP plane should be able to handle that. Pilot was ATP rated too…
wow, half the performance listed in the POH!
I'm about to do some high density flying so this video was nicely timed.