By Zac Noble
Not too long ago, I was taking off in an airplane, turning avgas into fun. I had the propeller pointing to the sky, climbing away from the ground and the airport below, when smoke began to roll out from under the instrument panel.
It was a nice clear day with blue skies and no other traffic in the area of the nontowered airport, so I just leveled off and did a 180-degree turn to return to the airport. I turned off the avionics master switch and landed back at the airport without further incident. A couple of days of troubleshooting ensued to find the instigator of my smoky encounter.
As it turns out, a nut from years past had fallen from someplace behind the instrument panel, perhaps lodged in a wire bundle or maybe wedged in a spot on a mounting flange, and landed right smack in between two poles of the master switch. The nut welded itself in place and caused the wires attached to the master switch to burn through, producing the smoke in the cockpit.
I searched for where it could have come, but nothing was missing a nut. The threads showed no sign of recent use. My guess is that during some maintenance or avionics upgrade, the technician dropped or lost the nut and, after a brief search with no success, simply replaced it with another one.
Years later, during my brief flight, I had found it. Lucky me. Two weeks earlier, I was flying that same aircraft in instrument meteorological conditions on a cross-country flight. Imagine what my situation would have been if that nut had fallen into the same position during that flight. As a minimum, it would have been high excitement.
Lucky me indeed.
This story isn’t unique or unusual. I think lost hardware is high on the list of things we try to avoid. It happens though, especially if the conditions are not as good as we would like. Maybe we are working on the ramp or at night, or both. Maybe it’s cold or wet, or both. And what if there is a time constraint we are trying to meet? What’s the fine line between moving quickly and moving too quickly?
A fellow pilot was attempting to start a helicopter at a hospital to transport a patient when he had a hot start on one of the engines. That seemed odd — a good pilot in a well-maintained machine — but the result was that the engine had to be inspected before subsequent starts could be performed.
A close examination found a couple of large paper towels had been ingested into the intake, choking off the cooling air needed for a nice start sequence. The patient didn’t get the necessary flight and had to be transported by ground, increasing the time of transport by a factor of three.
In 1975, while inspecting the Spirit of St. Louis, the airplane that Charles Lindbergh flew on the first solo transatlantic flight in 1927, technicians at the National Air and Space Museum discovered a set of pliers laying under the floor fabric behind an instrument panel. The tool appeared to be part of the original aircraft toolkit and is presumed to have been there since the airplane left the Ryan Aircraft Company factory in 1927.
We have gotten much better over the years, but tool control has long been a cause for concern in many operations. Unaccounted-for tools have contributed to many accidents or incidents in years past. As an industry, we have gotten the message on tool control and it’s likely if you visit a hangar, you will see that your maintenance technician has a nice set of expensive tools laid out in a handsome toolbox, with each tool having its own shadow spot.
Statistics show that few accidents are caused by maintenance errors these days, and the machines we are working on and maintaining are well-designed and manufactured. Even the older aircraft are retrofitted with new and improved components.
We have the perfect opportunity to turn this remarkable maintenance status into a phenomenal record of no accidents or incidents attributed to technician error. Let’s work together to reduce our input to accidents by keeping accountability of all things we touch in the maintenance process — including stray hardware and paper towels.