Entering a spin from a power-off stall???

[WestHouston]

I'm in a 152 with a student doing stalls. I have them do a power-off stall, dirty, and the plane drops the left wing an starts to roll into a spin to the left. I take the controls and recover. I tell the student "how the hell do you get into a spin from a power off stall?" So I take the controls to demonstrate the proper technique. IT HAPPENS AGAIN! Spin to the left, with 30 degrees flaps. When I was approaching stall, the warning horn was going off, but no buffet no shudder, and no sudden drop in the nose.

I decided to investigate. I put it in slow flight and backed off the power just enough to teeter on the verge of a stall, as it stalls all that happens is an EXTREMELY slow pitch-forward moment, like in a rocking chair, and then the bottom drops out and it spins.

Has anyone experienced anything like this in a C152 before? I thought maybe we had a far aft CG, but the W&B is good, even forward a bit as the student I was with is a short female with the seat all the way forward and sitting on two pads.

I'd like to find out why this is happening. I don't want any of my pre-private students to fly the aircraft until I do. Thanks!

 

[ekuflyer]

Have the flaps checked. Maybe they are not symmetrically deploying. Is it doing the same thing clean? Maybe the plane has been damaged/twisted somehow. Were you coordinated when it happened? Maybe the rudder is out of rig.

Just my 2 cents

 

[pblind]

Sounds like the flaps are out of rig. Happened to me before.

 

[Amish RakeFight]

Squawk the mechanic.

 

[socal_pilot]

We just had the same exact problem in one of our 152's. The flaps were out of rig a little and they replaced the flap motor, it fixed the problem.

 

[nosehair]

Thank you for your EverDay Real-Life Instructing Report.

Any readers here still opposed to spin training for students?

 

[ALIMBO]

I wish they would train us in them but I guess once I get my CFI ill get to do it.

 

[CFIcare]

Likely the rudder/flaps are slightly asymmetrical. Any time you are uncoordinated at the critical AOA, you'll initiate a spin regardless of power off/on.

I always demo-ed spins power off at first, as the entry was slightly less abrupt. It spins easier to the left in a 152 because the spinning prop helps in that direction.

To the right it's impossible as far as I know, to get it in a steady state spin (as in more that 3 turns) I went out repeatedly, with different fuel configurations, in attempt to get established to the right, and it always goes steep spiral whether you cross control, choke the crap out of it, etc. The prop counters the rightward rotation in this case and it literally will recover itself if you just let go. Fat guy on the right doesn't even seem to matter. Too close to the spin axis.

Good to see that you are actually doing spins with students. I used to show them, enforce that they are not to take flight school airplanes out to to this unsupervised, and then I'd set them up with an aerobatic instructor in a Citabria if they wanted to explore further...

 

[pilotx86]

uhm....the answer is simple..its a freakin 152....lol! J/K

the plane is probably twisted, too many hard student landings, excessive G loads from botched maneuvers bending the wings, flaps are not extended symmetrically, inclinometer not perfectly centered, rudder out of rig, etc..good luck

 

[WestHouston]

the plane is probably twisted

Always good words to hear...