Thrust - Reverser In-Flight Lock


Well-Known Member
For you airline pilots(or anyone else):
Is it possible to have a thrust reverser lock in flight. If so, what are the procedures to overcome this? Just curious.
Lear Jet

Memory Items:

1. rudder & ailerons - as needed
2. Thrust Lever (affected engine) - idle
3. TR Controls - Off
4. Above V1, accelerate to Vr.
5. Rotate at Vr, climb V2
6. Positive rate - gear up
7. v2 +30 flaps up.
8. if the deploy light remains on, shut down engine


9. Fuel jettison - on
10. Fule jettison - off prior to touch down.
How hard is it to maintain directional control with one or both TRs deployed? Can you demo it on a training flight, or is it a purely hypothetical horror?
the squats prevent the TR from deploying unless there is weight on the wheels. I suppose it cold malfunction, never thought about it to tell you the truth.

But no You don't do anything like that in a training flight, next time I am at SIMCOM or FS I will ask the instructor if we can do it in the sim, see what happens.

I'd like to hear about it. When I did the Citation ride with ATP the instrucor made it sound like an in-flight deployment would spell our death, and asymm. ground deployment would mean a certain ride through the bushes.
I believe there was a 767 that crashed in Tailand a few yera ago because the TR's deployed inflight.
There was a MD-11 that had the thrust reversers deploy inflight up near Alaska. I dont remember the exact details but a lot off altitude was lost. At one point I think they said it was deployed by a flight crew member.
I've done it in the sim. The sim just shakes like crazy until you get your speed down, and then it just shakes a lot. The yaw wasn't much worse than a normal engine failure at low speeds. Yaw isn't a big deal in a 727.

I think we ran the checklist and got it stowed in our scenairo...but the plane has been flight tested and certified laning with one deployed, I think it's an FAA requirement.
One of my professors at Riddle had a reverser deploy after takeoff in a 717. They were at around 4000 ft when the reverser deployed and he said the plane almost instantly rolled into a steep bank. Fortunately they were able to gain control, shut down the engine, and come back in for a safe landing. He showed us some pictures they took after landing of the deployed reverser. Just looking at the huge clam shell doors you could see the problem it would cause.
Clamshells? On a 717?

Hello I thought it had diffusers. Anyone with "Sissy Whisperjet" experience on here?

Had an inadvertant TR deploy on the RJ right after lift off. We yawed right and started a very slow roll. It was quite easy to control and still climbed very well. But this is a diffuser plane, not clamshells.
How hard is it to maintain directional control with one or both TRs deployed? Can you demo it on a training flight, or is it a purely hypothetical horror?

[/ QUOTE ]

Gentlemen that is why God invented simulators. Cessna had an airplane take off and have both buckets deploy. The aircraft had been in maintenance and the breakers to the emergency stow system were pulled, in addition to that the clamshells had been broke over center to facilitate polishing them and when stowed neither over center lock was made. = Bent airplane. Cessna also shows the certification film for an inadvertant deployment ... at speed ... hang on you are going over on your back. Directional control is proportionate to the speed at which the buckets deploy. Also on the cessna's if a bucket deploys the snatch back cable pulls the corresponding throttle to idle, hope no hands are in the way. During departure briefing we agree that in the event of an inadvertant deployment who ever gets to the emergency stow switch first wins a free beer.
I read a report recently when an airline turboprop accidentally reversed the props in flight, the capt pulled the throttles back to slow down somehow not realising they were already at idle, the engines overreved big time and passengers reported seeing sparks and bits of turbine flying out of the engines, they made an otherwise uneventful emergency both engines failed landing at a nearby airport. Funny thing was the whole time neither pilot knew why the engines had 'flamed out' until the mechanics figured out what happened.

Heres a little trivia I once read for ya: NASA trains on a Gulfstream (Believe the GII) using TR for practice shuttle approaches. Read that in AOPA Monthly flying mag a few months back.
Recently, on a sim check on the CRJ-700, I had a TR deployment. Lots of vibration and noise. Yaw wasn't too bad. Of course it didn't wan't to climb very well. It was pretty nasty, but flyable. No telling if the real airplane would be the same. I imagine that you could fly it, but I reckon it wouldn't be a lot of fun.

TR deployment on takeoff in the old straight wing Citation was manageable in sim. In the real airplane however, I am fairly confident that you would be a gonner. Unless you were using a 65,000 foot runway.
I have a friend who flies night freight in an old Lear 25D at MDW. She said they were flying along and had a T/R unlock light, but it was still stowed. Since then, they aren't using T/R anymore... they pinned them closed. Interesting coming into MDW in a jet without reverse.

She also had a tail stall a while ago, on final for 4R in IMC. Broke out to see the train yards filling the windscreen. Was an interesting story, to say the least!
I've actually heard of a turboprop going into beta in the air. They lost about 7000 feet but managed to keep it flying.

We don't have an established procedure, but we did discuss the scenario in systems.

In the Jetstream, you should only get a beta light on the ground. A beta light means that there is pressure at the beta switch, so the engine can go into reverse.

Basically, if you get a beta light in the air, you just want to make sure that you go full forward with the power and condition levers. Pulling them back could put the engine into reverse.
How could it go beta unless they were at flight idle? You mean the entire prop assembly broke?

I think anyone who lost 7000' without feathering needs a 709 ride.