Stalls in the Pattern

[steveinindy]

If pilots of a 121 operator are inventing their own stall recovery methods, contrary to published company manuals, and contrary to how they are trained, then the training problem would be even more serious.

Actually the procedure they followed was developed by NASA during tests evaluating the issue of tailplane icing.

Didn't help being paired with a non-assertive crewmember who was still mostly disengaged (quite possibly from illness/fatigue/lack of rest).

Right. On that we agree.

In fact, no US certificated aircraft has been identified as being succeptible to "tailplane icing stall."

Um....Vickers Viscount, DC-4s, the Convair turboprops, YS-11s and Jetstream 31s all had fatal crashes as result. The DHC-6 also had issues. Non fatal incidents involved the Saab 340, DC-9/MD-80 series and the ATR-42. (http://www.skybrary.aero/index.php/I...cident_History)

The following comment is made on the cited page: "Stick Shaker/Stick Pusher

It is considered possible for a pilot to confuse the stick shaker with the elevator buffet condition, followed by interpreting the stick pusher as an elevator snatch. This reinforces the requirement to be aware of airspeed, configuration and pitch control forces. Misinterpreting the shaker/pusher for a tailplane stall could be a catastrophic mistake; conversely, misinterpreting the elevator buffet/elevator snatch behaviour for a main wing stall could be equally disastrous."

I have seen that previously mentioned in NASA papers on the subject. There's a LOT of NASA research on this for something that isn't a factor at all according to you.

I agree that a disengaged crew here played a major role and the "startle factor" was what sealed their fate. My point was simply that mindset can cause bigger issues than "stupid pilots".

To back the icing issue contention up (emphases are my own):
VICKERS VISCOUNT:
4/6/1958 Freelandville, Michigan Capital Airlines Flight 67 (I have a piece of this aircraft in my garage; we found it when we went to put flowers at the site on the anniversary of the crash)

PROBABLE CAUSE: "An undetected accretion of ice on the horizontal stabilizer which, in conjunction with specific airspeed and aircraft configuration, caused a loss of pitch control."

1/29/1963 Kansas City, MO Continental Airlines flight.

PROBABLE CAUSE: "An undetected accretion of ice on the horizontal stabilizer which, in conjunction with a specific airspeed and aircraft configuration, caused a loss of pitch control."
4/14/1963 Oslo, Norway Icelandair Flugfelag Islands flight
POSSIBLE NOT CONFIRMED
PROBABLE CAUSE: "The accident to TF-ISU is assumed to have been caused by the fact that, during the approach to Fornebu, the pilot lost control of the aircraft at such a low height that recovery was not possible. From the evidence available, it has not been possible for the Commission to determine why this happened. There are possibilities, however, that the cause may have been that ice formed on the stabilizer or that the propellers went over to ground fine pitch. The Commission considers that the latter hypothesis is slightly more than the former.


1/15/1977 Stockholm, Sweden Linjeflyg Flight 618

PROBABLE CAUSE: Ice on the leading edge of the stabilizer resulted in flow separation and stabilizer stall.

JETSTREAM 31:
12/26/1989 Pasco, WA http://aviation-safety.net/database/...?id=19891226-0

PROBABLE CAUSE: "The flight crew's decision to continue an unstabilized instrument landing system approach that led to a stall, most likely of the horizontal stabilizer, and loss of control at low altitude. Contributing to the accident was the air traffic controller's improper vectors that positioned the airplane inside the outer marker while it was still well above the glide slope. Contributing to the stall and loss of control was the accumulation of airframe ice that degraded the aerodynamic performance of the airplane."

1/30/1991 Beckley, WV

PROBABLE CAUSE: "Flight into known adverse weather conditions by the pilot, which resulted in ice accumulation on the aircraft and subsequent loss of aircraft control (tail plane stall) as the flaps were fully extended. Factors related to the accident were: the pilot's inadequate use of the preflight briefing service, inadequate training provided to the pilots by company/management personnel, inadequate surveillance by the FAA, and icing conditions."

YS-11:
1/10/1988 Yonago-Miho Japan (icing/slush on the horizontal stab prevented rotation for takeoff causing a runway overrun)
3/15/1989 Lafayette, IN Operated by Mid-Pacific Air

Those are just the ones I found in a quick search before I got bored with the exercise....

That's interesting, because "tailplane icing stall" is not mentioned in the Comair 3272 probable cause published by the NTSB.

By the way, I got my commuter crashes mixed up. It was the crash at Pasco, WA not Detroit that I was thinking of. Sorry about that.

[Ron Blum]

Going back to stalls in the pattern (takeoff, climb and landing), we need to do something different to get pilots to notice that something is about to go bad. I find this similar to the "cyclops" brake light in cars. I am old enough to have driven before they were mandated, so I notice them as different. Younger people that I talk to don't notice them (or think that they are the only brake lights). For them it is not more noticeable or out of the ordinary. For me, the same is true with LED lights (on cars, airplanes, trains, flashlights, etc.). What can we do for airplane stalls that will bring the pilot out of his/her happy place to shout, "YOU'RE ABOUT TO DO SOMETHING REALLY BAD!"?

[PA11]

When's the last time you guys have done stalls in your own airplanes?

[Joe Delene]

When's the last time you guys have done stalls in your own airplanes?

One of my more useful things I do is 'slow flight' at altitude in different configurations. A fair amount of the time I include full stalls. Low to the ground does not leave a very wide margin for recovery. I like to back up to what lead to the predicament, usually distraction or lack of attention to the more important matters. Instead of worrying about stall recovery at 800', I'd rather focus on attention to not get one's self in that flight regime.

[Ron Blum]

When's the last time you guys have done stalls in your own airplanes?

Regretfully, we sold our airplane, and I have nothing to fly at the moment ... not even at work ... and not even a sailplane. The sailplanes I stall on every flight (sometimes intentionally and sometimes unintentionally while thermalling). I would stall the P172D we had often. Personally, I enjoy stalling rental C150s with 40 degrees of flaps at full power (they go over on their back and spin well ... for a short time ... before they recover on their own). I love to learn, but this is what I do for a living, so my experiences are a lot different than most. I'd like to build another (long story) Wright 1911 glider, and I don't plan on stalling it ... ever ... well, maybe. My day job is to make airplanes that try to warn pilots that they are about to stall and stall in a well-behaved manner when they do.

[Bob Dingley]

When's the last time you guys have done stalls in your own airplanes?

I was lucky to stumble on to an old school CFI at the tail end of the CAA era. Clyde left Embry Riddle when they got rid of their Stearmans and opened up his own school. I was 17. You can guess how my training went. Stalls & slips at hour one. Pull the pitot line off the ASI at hour two. Spins at hour four. Change from wheels to skis at hour six. Solo at 7.5.
After solo, more slow flight and now accelerated stalls. Cross control stalls. I had more time at the edge of a stall than I had X-country. Instead of letting me waste time boring holes, Clyde told me to go up to 4,000 and stall the plane. But don’t release back pressure. Keep the wings level with rudder and let it enter the next stall. Repeat down to 3,000. Remember to clear the engine. Report back to him how many stalls in 1,000. It was 10.

When the FAA replaced the CAA, the flight test standards changed. Just in time for me to get my Private. CAA called them “power on” and “power off” stalls. They wanted to see you aggressively break the stall, don’t worry too much about altitude loss. We all know the FAA method. And we know what negative habit transfer is. I eventually saw negative habit transfer come full circle in helo check rides. Helos do vortex ring state recoveries. AKA: settling with power. It must be a “positive” nose down (or side slip) recovery like 20 to 30 deg. If it’s a tepid recovery, you accelerate down at the rate of a toolbox and the ground gets in the way. You can see 6,000 fpm on the VSI. Looks just like a deep stall.

90% of everything I know about flying, I learned in the back seat of a Cub. The other 10% took decades of burning other people’s kerosene staring at glass.

The accident that started this thread happened in safe, functioning, docile airplane on a nice day. I’ve got a sneaky feeling that we will eventually find that the PIC was incapacitated and the passenger had zero training. This should not be the accident that causes us to re-invent the wheel. I know of an accident ten years ago where a passenger pulled it off. Two lived, two died.

Bob

[WLIU]

But to speak to the issue of "when was the last time you did stalls" - Once when I did a BFR, the CFI commented that statistically, the average pilot who comes in for a BFR has flown less than 20 hours a year. And his observations matched mine that a very large percentage of the pilots out there are not comfortable flying in the low speed end of the performance envelope.

So the likely answer to the question of "the last time" might well be "two years ago at a BFR".

To speak to the observations in the last post, I suggest that our current training treats stalls as scary, avoid at all cost, events. Many years ago stalls and spins were treated as routine parts of the curriculum. OK, your average pilot does not NEED to know how to spin, but preaching ignorance is equally silly. I would suggest that the curriculum include a CFI demonstration of a spin and recovery, but we now have a population of CFI's who likely have done the minimum of two spins in their entire aeronautical lives. And we continue to wring our hands over stall spin accidents.

I think that I understand that LSA standards do not require an audible stall warning, unlike Part 23 and 25 airplanes. Is that correct?

Anyway, I will suggest that the current FAA training syllabus moved too far in the direction of over simplification and needs beefing up in the airmanship area.

Best of luck,

Wes
N78PS - I spin every flight. Inverted every other.....

[Ron Blum]

I would tend to believe the 20 hours/year and stall at the last BFR for the vast majority of pilots is true. Not only is training lacking, but aircraft certification has gone the same way. If an airplane is shown to be spin resistant or have a chute on it, spins are not required for the airplane to certify. Some of the aerodynamic changes to make an airplane spin resistant also keep the airplane in the spin and make it harder or impossible to recover. LSA, ultralights and experimental aircraft are all not required to have stall warning. (this is not the full regulation, but ...) Part 23/25 airplanes must have 5 knots/7% prior warning (part 23/25) and must be able to keep roll within 15/20 degrees (part 23/25) or have a pusher to prohibit aerodynamic stall. If roll is less than 60 degrees during all stalls, the pusher must activate 2 knots before aerodynamic stall, and if roll is greater than 60 degrees during any stall, it must activate at least 5 knots before aerodynamic stall. So, not only are our pilots not shown how to recover from a spin, the airplane may not be capable of recovering.

[WLIU]

I am not sure about the current batch of Part 23, under 6000lbs, airplanes not having to have been spun successfully. Last time I looked the requirement was to be able to spin 2 turns and then recover within one additional turn with normal spin recovery control inputs. Aircraft that could not recover within one additional turn must be placarded "Intentional Spins Prohibited". So is the Cirrus placarded?

Best of luck,

Wes
N78PS

[Ron Blum]

Per current regulations, airplanes with pushers or those that are determined to be spin-resistant or those that have parachutes do not need to show compliance to the spinning regulation. The Cirrus states (I can't get this thread to accept an image), "Normal Category Airplane, No acrobatic maneuvers, including spins, approved". Ironically, the "d" in "approved" is removed by a screw.