Trim Failure

[pelmet]

Looks like well handled by the crew and perhaps some good lessons to learn. It reminded me of the only trim failure I ever had which was on a turboprop quite a long time ago. It was noticed in the descent that the trim was not working one winter day. There was an alternate system with a separate motor but it didn't work either, so we ended up landing without the use of the trim. But then it was working fine on the ground. Seemed OK for the return flight. Some time later, another crew had the same issue and it seemed to be appearing intermittently. Crews were wondering what it could be. Then the theories started, such as it only happening on eastbound flights but not westbound flights. But, perhaps there was some accuracy to it as the altitudes could be different along with the OAT in one particular direction. Then maintenance figured it out and a different grease(or perhaps proper grease) capable of handling colder outside temperatures was used.

.....or so I was told.


The Sunwest Aviation Ltd. Bombardier BD-100-1A10 (CL35), C-FMIX, was operating as CNK350
on a flight from Edmonton (CYEG), AB to Calgary (CYYC), AB with 2 flight crew and 1 passenger
on board. During the initial climb, the flight crew experienced a horizontal trim malfunction. Power
to the horizontal trim was shut down and the STAB TRIM FAIL checklist was run. After all QRH
procedures were carried out a PAN PAN was broadcast and ATS was made aware of the situation.
Adjustments to loading were made in the cabin and the decision was made to continue the flight to
CYYC. As the aircraft approached CYYC a request was made for a long downwind to configure the
aircraft. A flaps 10, Vref plus 30 approach was carried out to an uneventful landing. ARFF met the
aircraft and confirmed there was no issues with the brakes and the aircraft was taxied to the
hangar.

Maintenance findings: Maintenance determined that the Copilot trim was stuck in the nosed down
position internally. They are still working with Bombardier to resolve the issue. AW300-27-0388
Rev 1 addresses a similar situation.

[PilotDAR]

If you have a trim failure such that you cannot trim nose down adequately (which happened to me in a Cessna 206), you can buy yourself some time, and relieve the pitch forces by allowing the plane to stabilize in a turn of an angle of bank which balances out the pitch force. Is you can then relax the downforce required to maintain level flight, you can begin to manage the problem.

[L39Guy]

Too bad the Indonesian and Ethiopian pilots didn’t know how to manage a trim failure like these guys did.