Jammed Elevator/Stabilizer Scenario

[HPNPilot1200]

We ran this scenario today in the CitationJet sim and it was quite an eye opening experience. Since the elevator is jammed and the elevator trim tab deflects opposite the elevator position you have to apply reverse logic manual trim deflection (nose down trim to go up and vice versa). Definitely a scenario to take a minute and think about how it would affect you in your airplane.

 

[BurtM]

We ran this scenario today in the CitationJet sim and it was quite an eye opening experience. Since the elevator is jammed and the elevator trim tab deflects opposite the elevator position you have to apply reverse logic manual trim deflection (nose down trim to go up and vice versa). Definitely a scenario to take a minute and think about how it would affect you in your airplane.

I have no idea how or what I'd do given that situation. Probably crash and get the red or blue screen. But 10 or 15 years ago AOPA had a Barry Schiff video where he demonstrated how to deal with jammed controls in a 172 and it was really neat. He opened the left cabin door to turn to the right, etc . I guess the gist of the video was use what you've got. Food for thought. Sorry to hijack your thread, I don't think there's a left door in a CitationJet.

 

[jnmeade]

I don't think there's a left door in a CitationJet.

There is ONLY a left door on the Citations I'm familiar with.

Good to practice the trim problem. One of the things, like a trim stall, that are not really all that much fun to do but are potential life savers.

 

[BurtM]

There is ONLY a left door on the Citations I'm familiar with.

Good to practice the trim problem. One of the things, like a trim stall, that are not really all that much fun to do but are potential life savers.

I meant a pilot's door on the left side like the old Commander twins had. Sorry for the confusion. Anyway, how does one practice a trim stall? I'll defer to your expertise on things like trim/tail stalls because that's something I never learned about, hopefully with good reason.

 

[Dan Thomas]

You can use power, too, for pitch. More power lifts the nose, less drops it. Makes for a fast landing, though, but better than no control.

Not sure that a Citation would respond the same as a 172 that way. Would it?

Dan

 

[Everskyward]

What? No pitch/roll disconnect?

 

[gcd89]

We ran this scenario today in the CitationJet sim and it was quite an eye opening experience. Since the elevator is jammed and the elevator trim tab deflects opposite the elevator position you have to apply reverse logic manual trim deflection (nose down trim to go up and vice versa). Definitely a scenario to take a minute and think about how it would affect you in your airplane.

Wait, how's that?

The trim tab moves the elevator??

 

[BurtM]

Wait, how's that?

The trim tab moves the elevator??

Depends on the trim tab size, the elevator/stabilator size and how fast you're going, dunnit?

 

[rottydaddy]

Wait, how's that?

The trim tab moves the elevator??

Not if the elevator's jammed, it doesn't. :wink2:
In that scenario, the trim tab becomes the closest thing you have to a working elevator. Not a whole lot to pitch the airplane with, but better than nothing.
But since moving the trim control for "up" makes the trim tab move down, and vice-versa, you have to use the trim control counter-intuitively.

 

[gcd89]

Not if the elevator's jammed, it doesn't. :wink2:
In that scenario, the trim tab becomes the closest thing you have to a working elevator. Not a whole lot to pitch the airplane with, but better than nothing.
But since moving the trim control for "up" makes the trim tab move down, and vice-versa, you have to use the trim control counter-intuitively.

Oh OK, I see what you're saying. Derp.

 

[Dean]

You can use power, too, for pitch. More power lifts the nose, less drops it. Makes for a fast landing, though, but better than no control.

Not sure that a Citation would respond the same as a 172 that way. Would it?

Dan

I would think it would be the opposite, with the engines in the back, reducing power would cause the nose to lift and adding power would push the nose down.

 

[HPNPilot1200]

What? No pitch/roll disconnect?

I can tell you're a Sovereign driver at heart!

 

[maddog52]

We trained for a rudder/elevator out scenario in the B-52. It called for a flaps up approach using the speed brakes for primary pitch control since they caused the nose to pitch up when you pulled the lever back. The technique was to slow to approach speed with the speed brakes in position three (mid way) and trim the stab. The AC would use the yoke for roll contol and the speed brake lever for pitch adjustments. Pull the lever back for up and push forward for down. He would actually stow his control column to counter the temptation to use it for pitch. The CP would work the throttles and adjust the stab trim due to the underslung engines. It was a very good exercise in crew coordination. I know of at least one crew that actually used it to get an aircraft on the ground.

 

[Skylane81E]

I would think it would be the opposite, with the engines in the back, reducing power would cause the nose to lift and adding power would push the nose down.

Speed increase will cause a climb and vice versa

 

[HPNPilot1200]

Not if the elevator's jammed, it doesn't. :wink2:
In that scenario, the trim tab becomes the closest thing you have to a working elevator. Not a whole lot to pitch the airplane with, but better than nothing.
But since moving the trim control for "up" makes the trim tab move down, and vice-versa, you have to use the trim control counter-intuitively.

Precisely. Very counter-intuitive.

 

[Velocity173]

Does the trim tab on a citation have enough authority to flare the aircraft for landing?

 

[Traveler0471]

in my J3, I'd open the door on the right side and lock the window in the hinged up position and slide the left window down. With the cub trimmed I could extend both arms out the sides of the aircraft and by changing the aerodynamics of my hands, I could cause the aircraft to roll left or right, also I could lean forward to lower the nose and lean back to raise the nose.

 

[HPNPilot1200]

Does the trim tab on a citation have enough authority to flare the aircraft for landing?

It should, but your control inputs have to be very very small. Even inputs more than slight up or down cause extreme pitch oscillations which can become so large that you can't recover the airplane before impact.