iPad Loose Causes Pilot’s Trim Wheel Jam, Leading to Emergency Landing

During descent, between four thousand and ten thousand feet, an announcement “Master Caution” lit up along with “AP Mistrim” illuminated. After the Master Caution switch was pressed, the announcement promptly extinguished. The Captain (the flying pilot) pressed and held down the AP disconnect button, thus disconnecting the AP. He then attempted to manually trim the aircraft, only to find that the elevator trim wheel was stuck and wouldn’t budge.

At that point, he asked me (the first officer; the non-flying pilot) to declare an emergency and request ground equipment to be ready. He then instructed me to run the checklist. I proceeded to carry out the checklist for both the AP Mistrim annunciation and then the jammed trim controls. The Captain skillfully landed the aircraft safely and we taxied to the FBO. After deplaning the aircraft, the Captain went back inside to troubleshoot the problem with the power ON. First with the electronic trim and then manually. Upon doing so, the Captain noticed something was moving beneath the trim wheel. During the descent, an iPad had somehow gotten lodged beneath the trim wheel and jammed it. To prevent such an occurrence in the future, I suggest that pilots utilize the pilot’s side pockets for iPads and the pilots’ rear pockets for the checklist. This way, an iPad won’t be able to slide beneath the trim wheel and cause a jam to the trim controls.

Flying With Jammed Trim

So, what should you do if your trim gets jammed? Firstly, transfer the flight controls to another pilot (if possible) and try to locate any foreign object debris (FOD) in the cockpit. Before proceeding to test the trim, follow your emergency/abnormal checklist. Continuing to trim might inadvertently stick the controls in a progressively worse and unrecoverable state.

You’ll have to exert more manual force than you’re accustomed to. If you’re stuck with too much nose-up trim, the flaps can help lower the nose as the aircraft flies at a smaller angle of attack. On the other hand, with too much nose-down trim, adding flaps could have the opposite effect.

Danger Of FOD In The Cockpit

We’ve all heard about the dangers of FOD on the runway. The posters warning of FOD debris and damage are a common sight in FBOs and flight schools across the country. But what about inside the cockpit? Do you always securely strap down all your luggage? What about your flight bag and your iPad?

There are numerous things that can come loose and interfere with flight controls, even your electronic flight bag (EFB). Thankfully, in this case, the iPad didn’t manage to disable something as critical as the elevator or ailerons. If you can use a solid mount or a kneeboard, it’s a much safer alternative than holding your iPad freely.