Stalls In Multi-Engine Airplanes

Alchemy

Alchemy

Well-Known Member
I'm working on my Multi-Instructor and I have a few questions about stalls....

Originally, I did power off stalls past the horn till buffet, and same with power on stalls (this was in the PA34 seneca, I'm doing the MEI in a BE55 Baron). However, the instructor I'm working with on my MEI says I should recover from the power off stall as soon as I hear the horn and the power on stall as soon as a stall-inducing pitch attitude is observed on the attitude indicator.

Does everyone else do it this way, and if so, how do you determine what the critical pitch attitude is for your airplane. It seems like it would be different depending on how fast you were climbing during stall entry....
 
I think your instructor might be thinking about the old commercial PTS, which states that you must recover at the first indication. The updated PTS says that you must "recover as the stall occurs," which seems to imply that recovering at the horn is not enough.
 
We're recovering "as the stall occurs" in the Seneca right now. Stall horn, buffet, recover. He may also be thinking of Vmc demos where you recover at the first sign of loss of directional control or a stall. With the air density in Florida right now, I have yet to see loss of directional control. I still have a little bit of rudder left by the time I'm pushing a stall.
 
The only stalls I know of that are to be recovered at the first indication are found in the ATP PTS. All stalls should be taken to the break, and I never taught Private and Commercial stalls any differently. Just get the airplane unstalled...please...ok don't spin. No...don't use the ailerons. Ok ok...my controls. Hmm..memories. Anyway, try doing power on stalls in a turbocharged seminole at 14,000 feet. 20+ degree pitch attitudes were just barely enough at a 30 degree bank to get her to stall. "Ok just pitch until the nose gear is on the horizon in the mirror. Good"
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I recovered at the horn on my MEI checkride and almost busted because of it.. Gotta do it at the stall.
 
The commercial PTS clearly states:

"Recognizes and recovers promptly as the stall occurs ..."

The private PTS clearly states:

"Recognize and recover promptly after a stall occurs ..."



In other words...

commercial = recover during the buffet

private = recover after the full stall
 
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Anyway, try doing power on stalls in a turbocharged seminole at 14,000 feet. 20+ degree pitch attitudes were just barely enough at a 30 degree bank to get her to stall. "Ok just pitch until the nose gear is on the horizon in the mirror. Good"
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Done that...54H checkout in the winter. Man, that's good times. Felt like I was going to the moon at 34". Too bad insurance doesn't let me fly it anymore. Argh.

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Since when is a buffet a fully developed stall. I don't have a PTS in front of me but I think the stall they're referring to is a fully developed one. I can maintain the definition of minimum controllable airspeed with a fairly healthy buffet in most ASEL types. But realistically the stall is going to break and the recovery is going to be initiated prior to the auto-recovery of the stall due to aircraft stability. Private recoveries just need to occur before they lose a massive amount of altitude. Bottom line both need to stall, I have had students nearly bust rides for taking it to the buffet, and I've flown with ATP students who take it to first indication which is buffet, horn or loss of directional control.

I may not teach any more but I know I'm right dangit!
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The commercial PTS doesn't say "fully developed"...

The only thing it says is "recognizes and recovers as the stall occurs..."

Correct me if I am wrong, but the only way to recover from a stall as it occurs , is to recover before it fully breaks.
 
I'll take it past horn to the buffet on my checkride, thanks guys.

I teach my private students to do the same thing....as soon as they feel the buffet, recover from the stall. Never heard a DPE complain about doing it that way.

In most planes, taking it too far past the buffet just gets too sloppy, especially with a student pilot at the controls.
 
I teach pre-private students to recover after the stall occurs.

The private pilot PTS says recover after the stall occurs.

Recovery after/during the buffet would be a "bust" according to the PTS.
 
Good to know, I'll be sure my primaries take the stall to the break.

However, in the 172 it seems that you are stalled right after the buffet. The airplane breaks and sinks....it is stalled.....it happens at about the same time. It's not like we have stick shakers going off 10 knots in advance. Sure, if you're in an airplane that has a real noticeable buffet that starts 5 or 10 knots above stall, then I could see a need to make sure the student keeps the back pressure in and take it all the way to the stall break. I'll keep that in mind if I ever find myself in a primary trainer that behaves this way.

This just isn't the case in a 172....you'll feel the yoke wobble for a second or so and then you're stalled.....

Maybe I'll go up when I have some time to kill and try to see if I can maintain slow flight with the yoke buffeting in a skyhawk. Doubt I could do it, but who knows.
 
OK guys...since you aren't familiar with the actual definition of a stall, we'll start from square one.
A stall occurs when the critical angle of attack of the wing is exceeded. Prior to this occurence, the FAA advisory circular on stalls states the following...

"Just before the stall occurs, buffeting, uncontrollable pitching, or vibrations may begin."

Therefore if you recover at the buffet, you have not recovered as the stall occured because the stall has not occured. Most designated examiners I know prefer that students exagerate the stall on the stalled side, rather than the unstalled side. Remember the Flight Training Handbook indicates to us as instructors that we are required to teach our students to recognize and recover from the stall, after it, or as it occurs. There is no stall to be recovered from if there is only buffet and pitch changes. The stall must fully break and the recovery must occur after the break has occured. Some aircraft like the Piper Arrow with the tapered wing are difficult to stall power on. The wing still wants to fly and further aggrivation is what will cause the impending stall to mature into a fully broken stall.

I've never done a stall where we didn't take it all the way to the break. If you don't take it all the way to the break, you tell me. What exactly are you accomplishing besides noting that you intentionally flew the airplane to the edge of the stall and then recovered? We're attempting to teach people how to react to recover from a stall when entered inadvertently close to the ground. I don't know many people that would intentionally stall an airplane close to the ground now do you?
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Another stupid FAA PTS change. Why in the world would you teach students to ignore the stall warning horn? Recovery should never be put off beyond the stall warning. Multiple full break stalls in a multi-engine a/c will eventually lead to disaster. Dumb, dumb, dumb. I wish the policy people at the FAA would talk to flight instructors before fooling around with the PTS.
 
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Multiple full break stalls in a multi-engine a/c will eventually lead to disaster.

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Why?
 
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There is no stall to be recovered from if there is only buffet and pitch changes. The stall must fully break and the recovery must occur after the break has occured.......................I've never done a stall where we didn't take it all the way to the break. If you don't take it all the way to the break, you tell me. What exactly are you accomplishing besides noting that you intentionally flew the airplane to the edge of the stall and then recovered? We're attempting to teach people how to react to recover from a stall when entered inadvertently close to the ground. I don't know many people that would intentionally stall an airplane close to the ground now do you?
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Caution on this methodology of thought when getting into swept-wing aerodynamics.......just a note to let people that it does get different when you start dlying those. No such thing as the stall break anymore.
 
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In other words...

commercial = recover during the buffet

private = recover after the full stall

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That's exactly the way I do it. Private takes it to the break, commercial to the buffet, ATP to the horn. More conservative as you progress through the ratings.

I do not and would not teach students to take a Seminole to a full break stall. In many cases it won't break cleanly, and the only indication you have that you are stalled is the VSI is pegged at -2000+ fpm.
 
Weird...I've never heard of people NOT stalling a twin. Then again I suppose it would be the death of someone to fly a twin engine airplane below Vmc for training purposes, so I guess when you teach stalls in a Baron you just take it to Vmc and then back up again because the airplane is so obviously uncontrollable at Vmc+5kts.

I've stalled a Seminole every flight for 100 hours in type, and I've never had a problem. If you're referring to the fact that a stall in a multi-engine airplane is an instant Vmc roll then that's fine. Pull the throttle back and get yourself out of the Vmc roll. Pretty simple. This fear is the reason that most people kill themselves in a twin. They have no capacity once the airplane exceeds 70 degrees of bank or 30 degrees of pitch.

The critical angle of attack of a swept wing aircraft is typically over 30 degrees, therefore a stall in a swept wing aircraft would be pretty aggressive. A CRJ for example will lose at least 4000 feet if its wing becomes even partially stalled. That's bad. But are we talking Seminoles or CRJs?

And for the record I think the stall break in the seminole is more obvious than in any other airplane I've ever flown. If you can't tell if your seminole is stalled you probably have a fairly critical stabilator problem. Might want to get that looked into.
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Slightly off the subject, sorry to hijack,

When I did my power on stall for my private checkride the DE said he wanted me to recover at the first indication of a stall. Thinking he meant the horn, I recovered when I heard the horn. He said, "No, recover at the first indication of a stall. Wait until you feel a buffet." Confused, I did the stall again and this time let it go until I felt a buffet. Then the DE, seeming kind of agrivated at what he thought was me being a smart aleck, said "Son I din't feel anything, let it go until you feel a buffet." Not knowing what exacltly he wanted at this point, I did the stall again but this time let it go to a full stall. He then said "there, that wasn't so hard was it?"
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Whatever..
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