First in-flight emergency!

whitepines

Pre-Flight
Joined
Aug 21, 2020
Messages
40
Display Name

Display name:
whitepines
Just had my first real, live in-flight emergency today....and it wasn't the classic engine failure that gets so much emphasis. Thought I'd post here to see if there's anything I should have done better, but at least the airplane is on the ground in one piece and waiting for the mechanic to look at it.

Airplane is a Piper Arrow III, retractable gear. Preflight was normal, trim wheel was operable and placed into neutral per the checklist. Runup indicated no problems. First indication I had of a possible problem was that the nose seemed a bit light compared to normal, but as this was very subtle and right before the normal rotation speed I figured it was just a bit of wind or similar.

Immediately after rotation I could tell something was wrong, I had to push the nose over hard and hold just to keep a semi-normal attitude and keep the airspeed from decaying below 60KIAS. I instinctively reached for the trim wheel and found it frozen in place, wouldn't budge. The electric trim motor was not running holding it there, it was just jammed.

At that point my main focus was on preventing a departure stall, so I kept forcing the nose down and retracted the gear; at this point I was able to keep the plane in a normal climb with a lot of forward pressure. At 400' AGL I did a quick controllability check to make sure it was even possible to put the plane into a descent, and since it was (with a lot of force!) I chose not to try to force the trim since I didn't quite know what was wrong with the tail feathers and didn't want to make an already borderline control situation worse.

Called pan-pan and flew a tight pattern back in, putting the gear back down early and deploying flaps to try to relieve some of the control pressure. Landing was two handed (basically needed to keep the yoke forward until the flare) but otherwise uneventful.

I was informed on the ground that this is a fairly rare occurrence in Piper aircraft. I did report it to the NTSB as a flight control malfunction since it seems to fit the definition, and will see if they need any follow-up or are just tracking malfunction type etc.

0.3 on the Hobbs, and a lot more excitement than I anticipated, but now I know how I'll react in the "real deal"....
 
Thanks for the report. Sounds like you did great. I am curious if you tried pulling the circuit breaker for trim, or did you conclude it was a jammed control?
 
It's old and hasn't been revised that I know of, but the Piper Electric Pitch Trim manual might be helpful. As far as "old", so is your plane, so at least it's a matching set.

https://www.comancheflyers.com/publication/view/piper-pitch-trim/

The trim jamming in PA28s is more common than you'd think. That can be a control continuity issue or something in the electrical system like a servo or clutch problem. We didn't have an official step in the checklist, but I checked the trim could be moved at the step to verify it was in takeoff position - manual wheel and electric if equipped.
 
Thanks for the report. Sounds like you did great. I am curious if you tried pulling the circuit breaker for trim, or did you conclude it was a jammed control?

Honestly I didn't really consider the electric trim as a potential fault, partly because the amount of force I was applying should have been able to override it and partly because it felt jammed further down the line (a tiny bit of bidirectional "slop" still in the trim wheel).

If I couldn't regain proper control I would have moved on to more troubleshooting in the unwanted climb, but since I had just enough control to land I figured it was better to troubleshoot on the ground. :)

The advice to fiddle a bit with the trim wheel just before rotation (assuming that's what "at the step" means?) is pretty good. If there's enough runway left to reject the takeoff, it'd be a preferable option.
 
Glad you're safe and great job!

Is the plane a rental or new to you or???? I'm wondering how familiar you are with it. I had a similar incident where the plane didn't feel quite right and wish I had gone with my gut and rejected takeoff instead.
 
interesting that you had to push forward hard yet the trim was set to neutral.

Yes, once on the ground it became pretty obvious that the trim had moved to full ANU. I know for a fact it was set to neutral after the run up (I always check that, don't like unexpected mistrims at takeoff), and that the trim wheel was free at the time, so I'm a bit mystified as to what happened and plan to ask just what was wrong with it after it's fixed.

The trim wheel also remained jammed after shutdown, FWIW.

Glad you're safe and great job!

Is the plane a rental or new to you or???? I'm wondering how familiar you are with it. I had a similar incident where the plane didn't feel quite right and wish I had gone with
my gut and rejected takeoff instead.

Pretty familiar with the plane, it is a rental but I've been flying it and a Warrior for basically all of my instrument time. Honestly I've felt worse ground handling on the takeoff roll just from a momentary gust, it was pretty subtle.
 
What’s your decision-tree on pan-pan versus emergency?

If I have flight controls malfunctioning, it’s sure an emergency to me.

That was actually something I was looking for feedback on. I called immediately after I verified I had enough control to land, so I had figured that a.) I could technically could keep the aircraft in the air for as long as my arms held out against the yoke force and b.) as long as I didn't try to force anything in the trim system the situation was unlikely to deteriorate further. This was all a bit of a snap decision as I was quite busy with the unhappy airplane -- I felt the situation required priority but not as much priority as, say, someone on fire.

I did realize I didn't really have a good conceptual model of how the trim system works. There's a nice video of the stabilator trim system working here that helped fill a number of the gaps, though I still wonder how the trim could move on its own to full ANU:

Only thing I can think of is maybe the electric trim activated uncommanded on the takeoff roll, and then it mechanically jammed at the stop. Will be calling the shop this week to see what they found...
 
I know I'll get roasted for this - but here goes nothing.

Pan-pan is something that I wasn't even vaguely familiar with until I was nearly 50 years old.

I've been an Amateur Radio operator since the age of 13, and involved in aviation all my life from age 2 onward. So I haven't exactly been living under a rock.

I don't know if Pan-pan is enjoying a renaissance, or what, however I don't believe 100.0% of pilots know what it is/means, if my personal experience counts for anything at all. I think I'd cut to the chase to promote clarity.

If I have any issue where my ability to keep my aircraft controlled is involved, it's an emergency. I want everyone possible to be out of my way, and I want runway of my choice.

If available, sure... roll some equipment, too.
 
During preflight outside the plane did you move the stabilator up and down, did the trim tab look out of sync?
 
During preflight outside the plane did you move the stabilator up and down, did the trim tab look out of sync?

Trim tab was in the neutral position. I've been taught not to move the stabiliator up and down manually from the outside, just to check the security of the connection between it and the rest of the tail section / controls. After landing you could see the trim tab way out of the normal position, but that's because of the changes that happened in flight.

I'm going to get more details tomorrow, but it appears there were two failures. Nearest we can figure out, there was an intermittent short in the electric trim that must have driven it to full ANU on the takeoff roll. The short, being intermittent, didn't cause the trim to lock into place, but a failed pulley in the tail section jammed the trim system into place at that point. Essentially it was an intermittent electrical fault that exposed / created a mechanical fault -- one of those million-in-one chances I guess.

I may add a step to the checklist: prior to checking takeoff trim, disable the electric trim system. Rationale being that it's a lot easier to deal with an intermittent electrical trim problem in cruise than immediately after rotation... ;)

My review of the new Piper Anti-MCAS? 0/10, would not recommend. Arms hurt after using. :D
 
Trim tab was in the neutral position. I've been taught not to move the stabiliator up and down manually from the outside, just to check the security of the connection between it and the rest of the tail section / controls. After landing you could see the trim tab way out of the normal position, but that's because of the changes that happened in flight.

I'm going to get more details tomorrow, but it appears there were two failures. Nearest we can figure out, there was an intermittent short in the electric trim that must have driven it to full ANU on the takeoff roll. The short, being intermittent, didn't cause the trim to lock into place, but a failed pulley in the tail section jammed the trim system into place at that point. Essentially it was an intermittent electrical fault that exposed / created a mechanical fault -- one of those million-in-one chances I guess.

I may add a step to the checklist: prior to checking takeoff trim, disable the electric trim system. Rationale being that it's a lot easier to deal with an intermittent electrical trim problem in cruise than immediately after rotation... ;)

My review of the new Piper Anti-MCAS? 0/10, would not recommend. Arms hurt after using. :D

Yes, add the check electric trim prior to take off run up. And there is no harm in moving the stabilator while you are outside the plane. That gives a good visual that the trim tab is moving freely.
 
I know I'll get roasted for this - but here goes nothing.

Pan-pan is something that I wasn't even vaguely familiar with until I was nearly 50 years old.

I've been an Amateur Radio operator since the age of 13, and involved in aviation all my life from age 2 onward. So I haven't exactly been living under a rock.

I don't know if Pan-pan is enjoying a renaissance, or what, however I don't believe 100.0% of pilots know what it is/means, if my personal experience counts for anything at all. I think I'd cut to the chase to promote clarity.

If I have any issue where my ability to keep my aircraft controlled is involved, it's an emergency. I want everyone possible to be out of my way, and I want runway of my choice.

If available, sure... roll some equipment, too.

I would agree with this. Flight control failure is an emergency. Panpan is an urgency, such as, for example a sick passenger and need to land asap.
 
I’ve never seen an arrow III with a fixed gear.

Fair enough! I didn't know if it was an option, like on certain models of the 172.

Yes, add the check electric trim prior to take off run up. And there is no harm in moving the stabilator while you are outside the plane. That gives a good visual that the trim tab is moving freely.

Good to know. If anyone tells me not to, I'll just recount my trim story... :D

I would agree with this. Flight control failure is an emergency. Panpan is an urgency, such as, for example a sick passenger and need to land asap.

I've heard the trim system referred to by various people as either a flight control or a pilot assist device. On the "larger" aircraft (that is, compared to the Cub or 152) I tend to consider it more of a secondary flight control than an assist, which is why I made the NTSB report. Is this a proper way to look at it, or is the trim always considered a flight control?
 
Trim tab was in the neutral position. I've been taught not to move the stabiliator up and down manually from the outside, just to check the security of the connection between it and the rest of the tail section / controls.

There is no harm in moving the stabilator on a Cherokee. Its actually good practice because you can see the yoke and ensure it is moving correctly. A lot harder to see the tail from the pilot's seat. The only surface on the Cherokee that shouldn't be moved by hand is the rudder, because it is easy to damage the connection to the pedals and nose wheel.
 
There is no harm in moving the stabilator on a Cherokee. Its actually good practice because you can see the yoke and ensure it is moving correctly. A lot harder to see the tail from the pilot's seat. The only surface on the Cherokee that shouldn't be moved by hand is the rudder, because it is easy to damage the connection to the pedals and nose wheel.

That’s what I was taught too, always check all control surfaces apart from the rudder during preflight . Check the rudder while taxing . Also, OP, did you do a box control check? Wondering if that would have caught something?
 
That’s what I was taught too, always check all control surfaces apart from the rudder during preflight . Check the rudder while taxing . Also, OP, did you do a box control check? Wondering if that would have caught something?

Yep, always check controls free / correct (box and look, including looking out the rear window at the elevator). Can't really see the rudder though when taxiing?
 
Something to consider........... Don;t be afraid to declare an emergency. I find so many pilots reluctant to "admit defeat" and ask for help. So what does "emergency" do for you? Well it means you can do ANYTHING you deem necessary to survive. Basically a get out of jail free card. Now that said, it gives all the support that can be rendered at your total disposal.
There is NO reason to be reluctant to declare an emergency if you are having problems and ANY kind! Better to declare and not need the help than to need it and not ask. Thats why the its done that way. No jeopardy.

By the way, nice job. Aviate, navigate, communicate. Always fly the plane first, you did that, great job.
 
Yep, always check controls free / correct (box and look, including looking out the rear window at the elevator). Can't really see the rudder though when taxiing?

Right you can’t see the rudder, though with sun at the right spot behind you, you might be. But when you do the rudder check on the ground, if there are any problems it shouldn’t be too hard to figure out. At least I hope so
 
Old Thread: Hello . There have been no replies in this thread for 365 days.
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.
Back
Top