As a student pilot, it amazed me how many nooks and crannies there were on the training airplanes I flew, plus the number of openings, doors, covers and access panels. I don’t know what I was expecting, but the fact all this is designed to be opened up for inspection and put back together took some getting used to.
As I progressed through training, certification, an instrument rating and, finally, ownership of a previously owned Beech A36 Bonanza, I got used to it. I even helped my A&P-IA with the annual inspection a few times. That just exposed me to even more nooks, crannies and access panels, of course. I made it a habit to closely inspect them after any maintenance was performed and during my preflight preparations.
The A36 has one access panel the Cessnas I used to fly didn’t: a hinged door under the left wing, covering the fuel drain at the bottom of the cockpit-mounted fuel selector. It has one of those quarter-turn fasteners with a funny-shaped flat portion that allows the pilot to twist it to lock the fastener in place and keep the door closed. Sumping the fuel-selector’s drain and checking the airplane for open panels and doors is one of the last things I do during preflight before climbing aboard.
And that’s what I did on the flight I’m writing about. Taxi, run-up and takeoff were normal, and soon I was climbing out of Grand Rapids, Michigan, on my way to Madison, Wisconsin, for a business meeting. Yes, across Lake Michigan. It was summer, and I had flotation devices aboard. I’d made the trip before, climbed up to 10,000 feet each time I crossed and knew that there was only a few minutes of the flight where I was out of gliding distance to land.
As I leveled off at altitude and let the A36 accelerate, I noticed an unusual noise. I considered turning back, but was pretty much halfway to the Wisconsin shoreline, so I continued. Once settled into cruise, the noise seemed louder, but all the aircraft gauges reported normalcy.
Nearing Madison, I started to descend, and the noise got louder. I debated telling Air Traffic Control and requesting priority handling, but I didn’t know how to describe the problem. I soon landed uneventfully, taxied to parking and shut down. Before unloading, I walked around the airplane and…there it was. The small door covering the fuel selector drain was hanging open. I don’t know if I missed it on the preflight, or if it opened on its own. I later had my A&P mechanic replace the fastener, to prevent it from happening again.