Subscriber question:
"I always do a thorough preflight after an annual inspection and have never found anything amiss. Is there anything special I should do in addition to a really careful preflight?" — Sarah W.
Dean:
“During an annual inspection, all kinds of things get taken apart, and it’s more common than we’d like that something will not be put back together perfectly. There might be loose screws, something might be improperly assembled, or there might be a panel hanging loose under the airplane.
A friend told me about a disturbing noise in flight on a Cessna 172 on the first flight after an inspection. After landing, he discovered the round panel for accessing the elevator trim actuator was hanging loose and was flopping in the airstream. One time, I had finished an annual inspection and I thought I had things closed up. I asked another A&P to look things over and he was satisfied as well. Later, I decided to do one last final check—and that’s when I noticed some loose and missing screws under the airplane.
For a check like this, a creeper is your best friend. Here’s what I’d recommend: Grab a Phillips screwdriver and a creeper; roll around under the airplane, front to back, left to right looking for loose or missing screws. One way to detect loose screws is to lightly move your fingers across the panel screws. A loose screw will often make just enough sound when you bump it to detect it’s not tight.
Don’t just walk around the airplane when you preflight after an annual inspection. Be sure to take a close look under the airplane as well.”
Have you ever found something wrong right after an aircraft came back from an annual inspection?
