Teaching private in a plane that won't stall

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Roger, Roger

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So as an addendum to my announcement about being part owner of a Tri-Pacer, I am now working on teaching the other owner toward his private. We started working on stalls and recoveries yesterday and were met with an interesting problem- in most configurations with 2 people on board the airplane does not have enough elevator authority to get a stall break. We can usually get a decent break (and if uncoordinated, even a nice wing drop) power on, but power off the only way to sometimes get a stall is to start with ~1500 rpm, dive the airplane to get some speed and therefore elevator authority, then yank the nose way up while pulling power and holding the nose up. Usually works OK straight ahead, and about 50/50 in a turn. Anybody have good input on how to deal with this? I think we might put a person or 2 in the back seats and repeat the experiment, my concern being the stomachs of the people in back. Perhaps if I get people who are already rated pilots, that won't be an issue.
 
Call your examiner, explain your problem. Mention that you can only get a power off accelerated stall. He might have a solution.
 
I've noticed the same problem in older model C-172s with only two people aboard. If you don't get the nose high enough at the start you'll run out of elevator authority before the wing stalls. I teach guys to do power-off stalls starting with an idle glide at Vref speed. From there, transition to the pitch attitude that will produce a stall and hold it in that attitude, increasing back pressure as the speed bleeds off, until you have nearly full up elevator and the wing stalls cleanly.

How do you set up your power-off stall?
 
Are you descending on the setup or holding altitude? I suspect you are holding altitude so try entering a stall from a descent and then after around a few hundred feet you pull the airplane into a stall.

If that don't work I would then attempt a stall by increasing the rate of pitch change. Take advantage of the elevator's control authority before you lose it due to the decreasing airspeed.
 
I'm having the same issue in the Symphony 160, the darn thing won't break but it just descends in a nose up attitude. Our chief pilot wants all primary students to do stalls in our 150 or 172 before getting handed off for the ride but until I get to visit with the examiner about it I'm not sure what he wants for the checkride.
 
I may be wrong, but I think I was told that any decent beyond the stall speed and in configuration was considered a stall for this particular DE. It was years ago though.
 
Roger said:
So as an addendum to my announcement about being part owner of a Tri-Pacer, I am now working on teaching the other owner toward his private. We started working on stalls and recoveries yesterday and were met with an interesting problem- in most configurations with 2 people on board the airplane does not have enough elevator authority to get a stall break. We can usually get a decent break (and if uncoordinated, even a nice wing drop) power on, but power off the only way to sometimes get a stall is to start with ~1500 rpm, dive the airplane to get some speed and therefore elevator authority, then yank the nose way up while pulling power and holding the nose up. Usually works OK straight ahead, and about 50/50 in a turn. Anybody have good input on how to deal with this? I think we might put a person or 2 in the back seats and repeat the experiment, my concern being the stomachs of the people in back. Perhaps if I get people who are already rated pilots, that won't be an issue.
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Make sure you get that nose up early, it should break into a stall. If not I agree with Krieger, call a examiner. Honestly though, get that nose up while you've still got some airflow, it may just be a weird CG characteristic.
 
Nihon_Ni said:
I've noticed the same problem in older model C-172s with only two people aboard. If you don't get the nose high enough at the start you'll run out of elevator authority before the wing stalls. I teach guys to do power-off stalls starting with an idle glide at Vref speed. From there, transition to the pitch attitude that will produce a stall and hold it in that attitude, increasing back pressure as the speed bleeds off, until you have nearly full up elevator and the wing stalls cleanly.

How do you set up your power-off stall?
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Well, the first attempt(me flying) was similar to what you describe-descent at approach speed, pick an altitude, then reaching that altitude simulate a landing flare, gradually raising the nose. I reached full up elevator and held it there, and the darn thing just sat there at about 55-60 MPH still flying nicely in a descent. Next attempt was the same, but instead of gradually raising the nose I abruptly brought it as far back as it would go when reaching my selected altitude. Again, no dice. I ran into a guy yesterday who took his ride with our local DPE in a Tri Pacer and he said for his ride he explained the stall behavior of the aircraft, demonstrated it to the DPE, and showed him the proper stall recovery procedure from the low-speed sinking condition and the DPE found that acceptable.
 
Interesting. I taught one of my students in a tri-pacer back in the day and I don't remember that problem. That is one safe plane to fly i'd say.
 
subpilot said:
Interesting. I taught one of my students in a tri-pacer back in the day and I don't remember that problem. That is one safe plane to fly i'd say.
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Yeah. Like I said, it WILL break power on, and that's something I'm emphasizing on our recoveries-don't let the nose come up like it wants to when you go full power, because I bet it WILL stall then. As for your TriPacer experience, it's hard to guess why the difference in handling... It could be as simple as weight and balance, but with an airplane that's more than 50 years old there are any number of other factors that could come into play as well.
 
Had the same problem. It was solved by putting weight in the back under a cargo net. Just make sure it doesn't exceed the weight per sq. ft. of the cargo floor.
 
I'll bet you anything someone along the line has messed with the stops. You're probably not getting full up elevator. I've seen this a number of times on Scouts & Citabrias with VG's installed. These airplanes have a really nasty break with a full stall. So someone, somewhere thought it would be a good idea to limit the up elevator travel to prevent the harsh break. The only problem is that it limits full aft elevator for landing & taxi.

This airplane could just be suffering from a little hangar talk, where everything happens to seem like a good idea....
 
I'll have to look, but most of the stops on the aircraft seem to be non-adjustable... Like on a cub, they are a welded steel bracket. Don't know off the top of my head about the elevator though, I'll have to pop my head into the tail and see.
 
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