A CE560XL elevator trim could not be moved using electric trim or manually on approach; so an emergency was declared. After landing the elevator and trim control was returned to normal operation.
Synopsis
A CE560XL elevator trim could not be moved using electric trim or manually on approach; so an emergency was declared. After landing the elevator and trim control was returned to normal operation.
Narrative
On our descent/approach; we had the elevator trim seize. It could not be moved electrically or manually. There was slight forward pressure on the flight controls; which the autopilot could not overcome. We declared an emergency; ran the appropriate checklist; and continued the visual approach to landing without further incident. I was acting PIC; but was not the pilot flying. I asked my partner if he was having trouble with the controls; which he confirmed. I then asked him that if he needed anything; to advise me to what extent he needed help and tell me how he felt about the situation and the controls. As we slowed; the forward pressure on the controls became more obvious; so at that point we decided to declare an emergency. My partner flew and talked on the radio telling ATC what he wanted while I ran the checklist. After running the checklist; I resumed communication with ATC while my partner and I discussed different possible scenarios of landing outcomes. After that; we felt confident with our decisions and the outcome as well as our preparation. We did not have time to brief the passengers and were too busy with immediate task at hand. After landing we regained full control of the plane and had normal taxi to the ramp. We had a similar situation on the preceding flight; but it wasn't noticed until on short final. However; the plane was in trim and it didn't affect the controls; but might have if we would have had to go around. Once on the ground the trim worked almost immediately then; so at that point I didn't feel a further discrepancy existed anymore. It has been my experience here at this company that when issues like this are discussed with Maintenance Control; it is usually shrugged off and we are told to continue on since the problem doesn't exist anymore. A maintenance issue for me had existed previously a few months earlier and I felt I was being strong armed by the company to fly and was told that I was 'not cooperating with the company.' I feel that this treatment and intimidation by the company lead me to believe that calling the company would not do anything about this issue. Next time when I have an issue I will call and stand my ground and rely on my own personal experience; not the company's inexperience or intimidation tactics to pressure me to fly when a possible maintenance issue exist that should be 'at least examined by a Mechanic before flight.' The bottom line this holiday/winter season; don't fly a broken airplane; even if you are pressured by the company or threaten to be brought to the crew base for retraining.
Second reporter narrative
I was the pilot flying in the right seat of this flight. Upon departure; I noticed the trim wheel was 'clicking' during use. Furthermore; it was slow to react. The aircraft was properly trimmed for cruise and trim was functioning; so we saw no reason to divert. Autopilot was able to trim itself correctly. Upon arrival; I disconnected the autopilot while on the arrival. At that point; the trim was completely unusable. Neither electric nor manual trim was available. We decided to declare an emergency due to the flight control malfunction and ran appropriate checklists. We had an uneventful landing. The next day I brought up the aircraft on the [maintenance computer]. The maintenance notes said; 'They have found that the elevator trim is [in] need of lube and is very dry.' This was very concerning to me as my first thoughts went to the flight that crashed due to a sheared jack screw because it had not been lubricated. This was my second declared emergency due to elevator trim failures inside of two months.
NASA callback
The reporter stated that on the previous flight on short final when the autopilot was disconnected; he noticed a slight pitch down which he was able to control with yoke input. When he attempted to input elevator trim to counter the pitch down he felt the trim wheel jerking as it was unable to move; affecting an elevator trim change. The next flight; described in this report; the frozen elevator had a much more serious pitch down after the yoke jumped forward when the autopilot was disconnected and pitch was barely controllable. The elevator trim was apparently binding because it could not move in order to affect an elevator position change and only great force resulted in any elevator control. ATC was advised that; 'We will not be going around;' when the emergency was declared. A short while after landing the yoke made an uncommanded movement and the crew was again able to move the elevator manually and the elevator trim became functional. The reporter had heard stories about ice binding control cables and is beginning to believe that ice was a factor in this event.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.