690B crash in northern Wisconsin

[Bruce Byerly]

Several good points re: excessive pitot heat on the ground which I have seen too much and done myself inadvertently, maintenance shortcomings, lack of rudder use in stalls,  flight idle rigging, etc. I have no idea what happened but I’ve done hundreds of stalls including full power, accelerated, and high altitude and I’m still here. The airframe has never been anything but honest for me but I don’t do the radical stuff anymore.

One of our favorite instructors took me out for banked stalls at 5,000’ shortly before his accident and I think that might have been what got him in the end combined with a poor pilot recovery and a fresh engine repair with who knows what rigging.  5,000’ isn’t enough to come out of a split s in a plane this clean and powerful. 

You have to keep it coordinated and that means power too. Asymmetric power is going to cause asymmetric stalls.  Bob Hoover used to spin the Shrike as I recall but I believe it was Jimmy Driskell who told me he quit doing it for a reason.  I don’t know and don’t intend to find out.

[Steve binnette]

Here is an interesting albeit a little boring video of spin research on a beech duchess.  Best part is the beginning and toward the end of the video. 

It clearly shows a spin in a twin can be recoverable.  I remember something about the 737 getting into a spin during certification flights when they had asymmetrical slat deployment.  The pilot was able to recover the aircraft from the spin.

With that said I will not be testing spins in my Commander any time soon!,  I will continue to train slow flight into the stall waning or even into a buffet.  All will be power off with a nose over for recovery.

One of the techniques  I needed to break myself of was powering out of the stall.  That was trained into me during simulator training at the airlines for many years. 

They expected you to recover with zero altitude loss.  Completely doable but could be an issue if you experience significant asymmetrical thrust.  They are now teaching lower the nose then apply some power, a little altitude Loss is acceptable.

If I got in a spin in my commander I would use standard spin recover techniques.  If the rudder will not provide enough authority to stop rotation I would try asymmetric thrust.  There is a good chance if you are in a spin in a commander it was caused by asymmetric thrust.  At least neutralizing the asymmetric thrust will help.

Interesting part of the video is that the power setting did not seem to have a significant impact on the recovery!

In the duchess they did up to six turns before applying std recovery techniques with successful outcomes every time.


https://youtu.be/wzM1VoAnwvc

[donv]

You know, I don't ever recall hearing anything about Bob Hoover spinning the shrike. Every show I saw in person, and every video I have seen, he always kept a big margin above stall at all times. Maybe he did it while developing his act, but I haven't heard about it.

I'm also not convinced that spin characteristics of a Duchess are relatable to those of a Commander. Maybe, maybe not, but I wouldn't count on it.

And finally, I'm slightly rethinking my N690LS scenario, since a very knowledgeable Commander guy told me that their ADS-B data didn't show any sort of slow deceleration. It was almost instant.

That said, I do think there is a problem with stall/spin accidents in Commanders, and I think it is one which has gotten worse in recent years. Not because anything has changed with the airplane-- it clearly has not-- but because the pilots flying Commanders are coming up through a very different training process than those who flew them in the 1970s and 1980s. In the 70s and 80s, you still found a lot of ex-military owner/pilots who were very comfortable with stick and rudder-- guys who started out flying P51s and F86s and stuff like that. And the level of experience of the professional pilots of that era was higher, and more of those guys flew tailwheel and knew how to use the rudder.

Bruce is absolutely correct that the airplane is honest-- if everything is lined up and the ball is in the center, no problem. It's when it sneaks up on you and things aren't lined up that it's a problem.

[Adam Frisch]

At 16:50 in this clip Bob Hoover specifically speaks about spinning the 500B  - and why he stopped doing it!

Funny as well, because I'd mentioned that if I ever found myself in such a situation and rudder couldn't break the spin, I'd use differential power to try to get out of it. Hoover mentions later in clip that that's just what he used to do on the P-38's. Didn't seem to work on the Commander, as he mentions, but that's probably because not was in almost a flat spin and it might work in a normal one.

https://www.youtube.com/watch?v=dXYxwwjhuQI

[donv]

Well, there you go-- from the man himself! Thanks for posting that, Adam!

[Steve binnette]

Yea that was interesting.  I really like the way he worked his way through the flat spin.

Full down elevator and max power to provide airflow over elevator.  The guy never stopped flying the airplane!

[Bruce Byerly]

At 16:50 in this clip Bob Hoover specifically speaks about spinning the 500B  - and why he stopped doing it!

Funny as well, because I'd mentioned that if I ever found myself in such a situation and rudder couldn't break the spin, I'd use differential power to try to get out of it. Hoover mentions later in clip that that's just what he used to do on the P-38's. Didn't seem to work on the Commander, as he mentions, but that's probably because not was in almost a flat spin and it might work in a normal one.

https://www.youtube.com/watch?v=dXYxwwjhuQI

I’m going to admit I was losing my mind trying to find a clip of him spinning the Shrike! Thanks for that!!!  He used to do a little snap over the top and then it was no more … I’m sure there is video somewhere …

But yes I’m with Don. We have a totally new generation of aviators, many whom really don’t know nor even care to understand the nuances of stick and rudder. Works great until it doesn’t. Personally I’m looking forward to flying the J3 once we get the new engine done, finishing a floatplane rating, and maybe doing something different such as a glider rating with my daughter Amelia who just turned 16 and solo’d! Real flying skills are perishable so need to be nurtured!  Commanders spoil you 99.9% of the time, frankly. I’ve never felt more intimidated that getting back in a Cub after 30 years of training wheel flying… 

[donv]

The NTSB concluded that this was a stall/spin, and part of a pattern of stall/spins in Commanders.

https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103984/pdf

[appleseed]

Thanks for posting that DonV. Although I did not see any mention of a pattern of stall/spin accidents in this report.

[donv]

You are right, actually. The pattern was listed in one of the news articles about the report, but not the report itself. I can point you to a number of 690 training accidents which followed a similar profile, although this was a little bit unusual in that it wasn't strictly speaking a "training flight" from what I can see.