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TAILspin38 wrote: ↑Mon Apr 25, 2022 1:25 am Should it not be a standard practice to stay above the airport and circle to gain altitude before departing the area heading towards the mountains? These unfortunate accidents really make me over anxious when trying to plan a family outing and W&B combined with DA come into play. Our condolences to the family and friends.

Yes, circle the airport until you have altitude to clear the surrounding terrain. Or follow the ODP.

The accident need not make you anxious. But it does underscore that W&B is not just a PPL exercise. It's fundamental to understanding the operating envelope of the airplane and the expected climb performance for each flight. The plane will perform as documented in the AFM. But it will not perform better.

If you accurately transcribe the AFM chart/table into several Foreflight custom performance profiles, each for a different takeoff weight, you can select the appropriate profile and FF will do the math for you. You'll never need to open the AFM. The Flight data will show your takeoff distance and the Profile view will show your clearance, or lack thereof, over terrain for your intended route. The FAA suggests at least 1,000' over terrain in flat country, and 2,000' over terrain in mountains. I consider those to be minimums.

Thanks Russ and all the other EXPERIENCED AVIATORS for all the input. Tragedy has a way of slowing things down and getting back to basics. I have Garmin Pilot and am unable at this time to change my W&B profile to the GWI of 2646. Possibly need to find an app.

Anthony, I was a very new pilot with our DA40, less than 400 hours, when I put the whole family in the plane and we flew across the country for the first time. I was extremely, extremely careful. Very conservative on every decision. One of those first crossings was right along that same terrain. The following day we were taking off out of Jackson Hole, WY. I don't think I have ever focused so much on a take off, climb, and keeping every turn shallow as I made the moving map turn from red to yellow to "we can continue along our route."

It's all a question of managing your risks.

Everyone determines their own risk tolerance, there is no right or wrong route, etc. to take. I fly many places and routes that others may choose not to. I love the fact that our plane can easily fly slowly, and fully loaded doesn't stall until 58 KIAS with flaps up and 30 degree bank angle (POH 5.3.4). When needed, our plane can make a 180 turn in about a 1500 ft diameter semicircle flying at 70 KIAS and 30 degrees bank. That can be dropped to about 1100 ft diameter u turn at 60 KIAS. ( https://airplaneacademy.com/radius-of-s ... rate-turns ) There aren't many slot canyons out there to fly into on accident that we couldn't get out of. I was taught the box canyon turn during training, but I don't think most are. Definitely worth looking up and practicing.

My family gave me a couple hours of aerobatic lessons a few years after we got our plane. So I learned the box canyon turn was well as the knife edge turn (it is called something like there) where you lose some altitude but can nearly pivot in place.

Back in 2007 a couple brothers went down a slot canyon in their DA40. Considering the situation they found themselves in I feel like they did incredibly well.

The assertion is made that a 60 KIAS at 30 degrees of bank in a DA40 results in a 1100 diameter u-turn. The implication is that this is relative to the ground. This is not true, especially not for all conditions. Airspeed calibration and density altitude come into play. At a modest 7000 ft. DA this adds quite a bit to the turn diameter. And this is in no-wind situations.

While I applaud the notion of making best use of the low-speed part of the envelope you don't want to be partly through the turn and put a wingtip into a treetop.

Knife-edge turn: Sometimes you may not have any altitude to spare.

I approach all my flying with a balance of confidence and humility. I've barely escaped several high DA situations enough times to realize how close it was. A good friend of mine totaled my Cherokee due to DA almost 30 years ago but without serious injury to him or his passenger by simply knowing "when to fold 'em" and put it down under control.

What I'm about to say has nothing to do with this accident since it is too soon to know much. I learned to fly in the Rockies and have been based in Utah for the past fifteen years. The most common DA related accident I read about is one where the pilot does the math and has ample runway for the takeoff. The pilot then points the nose toward rising terrain and tragedy shortly follows. With afternoon thermals and any sort of wind, a DA40 will not have a consistent climb rate. Sure the book might say 700fpm and experience may confirm that but once you get the updrafts and downdrafts going, your climb rate is going to average 700fpm and vary from -200 to 1,500 with no real way to tell which it will be and for how long. Plan accordingly.

What an unfortunate accident. I start at sea level, and I don't dare put 4 adults in my plane right now.

From Kathryn's Report:

“On scene, deputies stated, based off debris, aircraft orientation and damage to foliage, it appeared the aircraft crashed heading west from an easterly direction,” the ICSO update says. “Investigators from the Iron County Sheriff’s Office, along with investigators from the Federal Aviation Administration and National, National Transportation Safety Board will conduct a scene investigation to determine the cause of the crash."

Since the aircraft was heading east, initially, they must have at some point executed a 180deg turn and were headed for lower terrain. There could be so many reasons for the accident — mechanical, CFIT, downdrafts, out of CG — that we might not ever know the real cause given the poor state of the airplane and lack of radar coverage in the canyon. But there are a few lessons to extract regardless of cause:

1. Yes, Diamonds _can_ experience a post-crash fire — I think we've had a couple of these recently. How can we prepare ourselves better for this possibility?
2. Even if legal, flying close to your W&B limits places a special onus on the pilot to reduce risk in other areas of flight, and here we know that the pilot was already at the limit in at least a couple of other ways (high DA, mountain flight, canyon with climbing terrain). How can we establish a safety culture for ourselves to more thoroughly offset risks that we choose to take with ones we explicitly don't accept?

Looking at Flightaware, it looks like he was going up the canyon and just ran out of clearance. His climb rate was very lethargic so I wonder if he was staying low for site seeing and didn't realize the rate at which the canyon floor increased. Using hazard advisor in FF you can easily see how the canyon he was in had a rapidly increasing floor. Dang this sucks...peace and prayers to their families. As a father of three I feel so much grief for those four children. Ugh.

Here is a good analysis of an accident last year where density altitude and trying to out climb the terrain seem to be factors. Whether it is or not in the recent accident, this video describes the problem nicely:https://youtu.be/8PBUVMCbmFQ.

These AOPA safety videos are a good resource. Others on YouTube that I recommend are Flight Safety Detectives and Blancolirio. The jury is still out (with me anyways) about Dan Gryder.

Learning from other’s mistakes is a great way to avoid them yourself.