Aileron to flap alignment

[Doug G.]

Yes, I never use aileron for control near stall because it has lotto effect except to add drag on the wing you are trying to lift. Opposite rudder in effect speeds up the low wing and slows the high wing with more authority ( because of prop wash) than you can get from this ailerons. (Yes, I know they are flaperons.)

Look at me talking like I am a CFI...

[Runtoeat]

My experience doing stalls with all flap and power settings indicates that rudder input by itself provides adequate recovery, This is predicated on me going into the stall in a coordinated condition. As I approach stall, I seem able to fully control direction with rudder, fully capable of doing 360 degree turns, etc. As the stall finally progresses to a point that a wing might start to drop, opposite rudder stops entry into a spin. Based on the good response using rudder, I would anticipate that there would be good recovery using rudder even if I wasn't coordinated but I haven't pushed the envelope. I don't enjoy flying under these conditions and will try to have an experienced pilot sitting next to me.

[Jim Meade]

Airplane Flying Handbook page 4-5 to 4-6. USE OF AILERONS/RUDDER IN STALL

RECOVERY.

 

Here's the discussion later on about power on stalls:

 

FULL STALLS POWER-ON

Power-on stall recoveries are practiced from straight

climbs, and climbing turns with 15 to 20° banks, to

simulate an accidental stall occurring during takeoffs

and climbs. Airplanes equipped with flaps and/or

retractable landing gear should normally be in the

takeoff configuration; however, power-on stalls should

also be practiced with the airplane in a clean

configuration (flaps and/or gear retracted) as in

departure and normal climbs.

After establishing the takeoff or climb configuration,

the airplane should be slowed to the normal lift-off

speed while clearing the area for other air traffic.

When the desired speed is attained, the power should

be set at takeoff power for the takeoff stall or the

recommended climb power for the departure stall

while establishing a climb attitude. The purpose of

reducing the airspeed to lift-off airspeed before the

throttle is advanced to the recommended setting is to

avoid an excessively steep nose-up attitude for a long

period before the airplane stalls.

After the climb attitude is established, the nose is then

brought smoothly upward to an attitude obviously

impossible for the airplane to maintain and is held at

that attitude until the full stall occurs. In most

airplanes, after attaining the stalling attitude, the

elevator control must be moved progressively further

back as the airspeed decreases until, at the full stall, it

will have reached its limit and cannot be moved back

any farther.

[FastEddieB]

Note that full power combined with full flaps is not mentioned.

 

I did one unintentionally as a student. I think I went into a departure stall after an approach to a landing stall where I forgot to raise the flaps. The roll to the left at the break scared the poop out of me at the time.

 

Anyway, this is not a normal configuration or training exercise.

 

I did teach aerobatics, so full power combined with a stall and rotation is not new to me, as in a snap roll.

 

I'd just approach the full power, full flap configuration VERY cautiously and with a LOT of altitude, especially in a plane not authorized for spins.

[Tom Baker]

Jim and Eddie, he was not practicing stalls he was doing what is required to calibrate the AOA on the Dynon. I have done this before and it is different from any kind of stalls that we teach. I think he was foolish for doing this at night without good outside references for pitch, heading, and roll. I also think fixating on the ball was not a good thing either.

 

Also he says his application of aileron was prior to the stall and not during the recovery.

[FastEddieB]

Jim and Eddie, he was not practicing stalls he was doing what is required to calibrate the AOA on the Dynon.

 

Thanks for the reminder - I had forgotten that.

 

Still, I'm not surprised that combining full power with full flaps can give rather drastic results - I would approach them with a LOT of caution.

[Anticept]

I think he was foolish for doing this at night without good outside references for pitch, heading, and roll. I also think fixating on the ball was not a good thing either.

 

Indeed, hence why I only did it once when I realized how incredibly unpredictable it was!

[Doug G.]

OK, I don't see where he said FULL power, I only see " power on." I have done power on full flap stalls, but not full power. It would seem that at full power you would have to be at a very high angle to keep below the 62kt max. Vfe

[Tom Baker]

OK, I don't see where he said FULL power, I only see " power on." I have done power on full flap stalls, but not full power. It would seem that at full power you would have to be at a very high angle to keep below the 62kt max. Vfe

 

Doug, you are correct he didn't use the term full power, but based on what he was doing and knowing the procedure I figure he was. Here are the 4 stall configurations Dynon wants for calibration of the AOA.

1. With full power, no flaps
   
2. With no power, no flaps
   
3. With full power, full flaps
   
4. With no power, full flaps
   

[Tom Baker]

Staying below 62 kts prior to the stall shouldn't be much of a problem, just get the airplane slow before going full power. I would bet that he exceded it before he got recovered.

[Jim Meade]

Jim and Eddie, he was not practicing stalls he was doing what is required to calibrate the AOA on the Dynon. I have done this before and it is different from any kind of stalls that we teach. I think he was foolish for doing this at night without good outside references for pitch, heading, and roll. I also think fixating on the ball was not a good thing either.

 

Also he says his application of aileron was prior to the stall and not during the recovery.

 

I know he was doing calibration stalls. The discussion got to addressing power on stalls in general, I thought, thus my response.

 

I've done the calibration stall and do pretty much like a FAA power on stall, except that I'm at 40° flaps rather than take off flaps.

 

To me, the way to keep power on stalls from getting too radical is to slow the plane down as much as you can, apply flaps as needed/desired for the maneuver, add full power smoothly and quickly and pull back on the stick smoothly and quickly. Use rudder as needed and ignore the ball - look at the horizon. You'll have ot add rudder quickly. That is the way I've done my calibration stalls.

[Anticept]

OK, I don't see where he said FULL power, I only see " power on." I have done power on full flap stalls, but not full power. It would seem that at full power you would have to be at a very high angle to keep below the 62kt max. Vfe

 

Actually the flaps add so much drag at max setting, that you can almost be horizon level. I fly in and out of a lot of grass fields, and it's really weird how my CTLS takes off with short field takeoff with obstacle clearance (MAX Vx configuration), it will get up to speed, just start to get off the ground and ride ground effect, then suddenly shoot upwards while the nose is still level with the horizon through the maneuver. It's like she jumped on an escalator and is riding it into the sky. If I am not careful and don't drop the nose to the horizon after wheels leave the ground, I can risk stalling. None of the other planes that I have flown do this.

 

I haven't done it post-re-calibration though. Might have been the fact the AoA was off.

[sandpiper]

Did you ever watch a single engine DHC-3 Otter climb. Slightly nose down attitude while going up. Kinda like a helicopter.

[Doug G.]

Yes my CTLS is the same. I assume you are talking about flaps at 15°. For you CTSW folks 35° is max on the CTLS. I believe the Si is limited to 30°.

[Anticept]

Yes my CTLS is the same. I assume you are talking about flaps at 15°. For you CTSW folks 35° is max on the CTLS. I believe the Si is limited to 30°.

 

Flaps 35. I just noticed the manual doesnt list using 35. wonder if 15 gets off the ground a little faster? Something more to test!

 

EDIT: oops. I said short field. I have been meaning soft field.

[Runtoeat]

Anticept, you might find this former thread interesting.

http://ctflier.com/index.php?/topic/1657-rough-field-take-off/

[Anticept]

Anticept, you might find this former thread interesting.

http://ctflier.com/index.php?/topic/1657-rough-field-take-off/

 

Check the thread. I put in my two cents!

[Ed Cesnalis]

How does a calibration stall become a stall / spin entry?

1. Rotation had to be permitted and it likely was by focusing on the ball and not paying attention to your heading. You were rotating left. Proof is the need for full right rudder to recover.
   
2. You were in the process of stalling the wing.
   
3. Full right aileron to pick up the left wing countered the left rotation and snapped into the spin. Your controls end up positioned for a snap roll, full flaperon and full stabilator opposed by enough rudder till it finally broke.
   

To prevent do the calibration stall strait ahead and use rudder to (prevent rotation and pick up the dropping wing).

[Anticept]

My plane is flying a lot right now, so i haven't been able to get a slot to take her up to try again. 6FD is EXTREMELY popular.

[Tom Baker]

How does a calibration stall become a stall / spin entry?

1. Rotation had to be permitted and it likely was by focusing on the ball and not paying attention to your heading. You were rotating left. Proof is the need for full right rudder to recover.
    
   
2. You were in the process of stalling the wing.
    
   
3. Full right aileron to pick up the left wing countered the left rotation and snapped into the spin. Your controls end up positioned for a snap roll, full flaperon and full stabilator opposed by enough rudder till it finally broke.
   

To prevent do the calibration stall strait ahead and use rudder to (prevent rotation and pick up the dropping wing).

 

Full right aileron might have picked up the left wing, but it would have enhanced the left rotation because of the increased drag on the left side of the airplane.

[coppercity]

I had to go try full flap power on stalls this morning after following this thread and I have to say it was a non event.

 

The first several I performed at full flaps using the following technique. First slowed into the flap operating ranges maintaining level flight until full flaps 35 deg in my LS was set. I then maintained altitude and reduced power to get to around 40kias. I then pitched up smoothly then added full power while smoothly increasing pitch and right rudder for coordination, maybe slight right aileron to counter act the rolling torque. Stall was easy to see with mild buffeting followed by a Uncommanded drop in pitch followed by slight pitch up again ( what I would call nose bobble). IAS at this point was around 29kias with increasing rate of descent, no noticeable wing drop even holding it in the stall condition. Recovery was instant with a slight pitch down stick command. I did this several times at each flap setting from 0-35. The only time I got a mild wing drop was when I was intentionally uncoordinated and aggressive with the pitch up command to stall, again recovery was instant with a pitch down to break the stall then a roll back to wings level.

 

 

[Tom Baker]

For the calibration process you only have 45 seconds to complete the stall. Otherwise you have to start the stall sequence again. When you start the timer things can feel a little rushed.

[Doug G.]

Try 15, I think you will notice a real difference. I have never tried a full flap takeoff. You get a lot of drag and not much (if any) lift.

One thing I like about this plane is that going full throttle with any flap setting will let you climb.

[Anticept]

Got back from my tests. Feel free to check the other thread about Runtoeat's and my testing of 15 vs max flaps for soft field takeoffs.

 

ON TO BUSINESS:

 

Full Flaps (35 degrees), Full power stalling. 3 tests.

 

Pitch has to be over 20 degrees positive

29 kts reading on the airspeed indicator before the plane will stall (I held 30-31 for 10 seconds to verify).

Right rudder, even when maxed, is NOT enough to stop the left roll tendency. It's just too strong, aileron must be used.

Ball is reading correctly, my string confirmed.

 

First, I tried to hold the ball in the center, held heading, and used aileron to correct. On stall, left wing drops, nose pulls towards ground. I react more quickly and prevent anything from developing. After the maneuver was complete, I was at 50ish kts and 30 degrees left.

 

Next, I tried instinct and feel. Kept the ball centered until it stopped feeling right. Then strictly by observation outside and the feel of things, I ended up with much greater right rudder with the ball significantly left. Left wing still drops a little bit, but the nose doesn't pull left much, and maneuver recovers very quickly.

 

Finally, tried max right rudder to see if I can get the right wing to stall. Left wind drops slightly, but nose stays on course, and just sorta mushes. Difference in rudder from previous maneuver above is not much though.

 

I can't seem to prevent the left wing drop out before the right wing does through this. However, the max right rudder does help. I think the ball just can't be trusted at such extreme pitch angle and slow speed due to p-factor pullting the plane left from the slow speed and high pitch, and when I do this with cruise power or no power, it is very controllable. Also, I had a double take when I saw the 30 kts!

 

I'll check rigging sometime to make sure it's not a rig issue. Thanks coppercity for the comparison notes!