Training and Safety Tip: Prepare your passengers
I recently flew with a first-time single-engine piston aircraft passenger. My plan was to do an hourlong local sightseeing flight, a route that I had done numerous times before and knew well.
When I started my aircraft and the avionics powered up, I was met by a big red X on the primary flight display. Over on the multifunction display the worrying message appeared: “ADAHRS hardware fault.”
My passenger shifted in his seat, nervously.
I told him that I wasn’t sure what was going on, but that I’d shut down the aircraft and call a CFI friend. If I couldn’t solve the issue, we would not go. I made the call and my friend told me, “Maybe just try to reboot it, like a computer. Shut it off and turn it on again.”
I started the aircraft up again, and both screens immediately powered up to look normal, as if nothing had ever been amiss. My passenger’s discomfort did not abate.
“Hey, can we maybe do a little shorter flight than we had planned,” he asked.
Absolutely, I answered, and I also suggested we do a lap around the pattern at our home airport before heading out, just to make sure everything was working properly. We took off into a beautiful morning. The uneventful lap in the pattern gave me some landing practice, and then we proceeded on our way.
About 20 minutes into our flight, my passenger was obviously enjoying the ride.
“I know we’re not supposed to change plans in the air, but I’d love to go a bit further,” he said. I smiled and told him, of course we can do that.
Later that day, I learned that an ADAHRS (air data attitude and heading reference system) hardware fault indicates “a critical failure in sensors, wiring, or power.” It makes itself noticeable by displaying as a big, ominous red X on screen. Common causes can include loose connectors, wiring issues, magnetic interference, or inadequate power during engine start. It’s a pesky, temperamental glitch, but one worth troubleshooting before leaving the ground. You don’t want to venture far with wonky avionics, and you definitely don’t want to do it with someone making their first flight in a small airplane.
The moral of the story? Prime your passengers for any eventualities, up to and including canceling the flight completely if something is wrong. Setting expectations early and keeping them informed about progress is the best way for both of you to enjoy your flight. Your personal minimums should be a guide for dealing with any unexpected events like my hardware issue, and erring on the side of caution is always the best idea.
