Aircraft Maintenance: Aircraft clock repairs

A functional clock must be mounted in the aircraft for instrument flight per the federal aviation regulations (14 CFR 91.205).

In many aircraft, the clock may be one of the last remaining original instruments, grouped along with other “classic instruments” such as fuel gauges and oil temperature gauges. The fact is that, with the modern reliance on GPS approaches, the use of a clock for instrument flight is fairly passé, but it still matters and is a critical part of your fallback options if your GPS system were to fail.

In a time when even disposable kitchen timers seem to be outdated by the clock on your phone, paying hundreds of dollars for a new certified aircraft clock can seem absurd. And so I began digging for options. There was the usual option of “Velcro a kitchen timer over the broken clock,” but I'm not really a fan of patchwork repairs after all of the blood, sweat, and tears (literally) that I’ve put into my panel. So, I looked into repairing my existing clock and was pleasantly surprised.

Davtron has been around since the 1960s and is the brainchild of Dave Torresdal. Torresdal’s first foray into avionics was the creation of a digital ADF indicator in his 1958 Comanche, but he soon moved into certifying digital clocks to replace the mechanical wind-up clocks that were the mainstay of aircraft panels at the time. His first clock, the 811B digital clock, has sold over 40,000 units worldwide and is still in production today.

I knew that Davtron was the proverbial granddaddy of aircraft clocks, but I didn’t know how personally they take their business. When I contacted them about my failing MB800 clock, they were quick to recommend that I send it in to them for a complete repair/overhaul to like-new condition. With a flat labor rate of only $70 for all repairs and fairly inexpensive parts (if needed), most repairs are well under $100. You can’t do much of anything for less than $100 in aviation these days, so I quickly boxed up the clock and shipped it out.

I asked them to take a few photos of the repair process, so I could see what was involved. It was an interesting throwback in time getting to see the manual solder repairs to the through-hole PC board, but I was really impressed with the quality of the repairs and the attention to detail along the way. They even took the time to replace the wire harness and the faceplate. The result, I’m sure you will agree, is that the clock looks and works like new. It’s one of those repairs that you do and think: “Why didn’t I do that sooner?”

Aircraft clocks aren’t something that normally garner much attention. But, if you’re planning on instrument training or actively flying IFR today, it pays to give that little instrument some attention. After all, if those big moving map screens were to go dark, it would be back to the compass and the clock for all of us to get home through the clouds.

Until next time, happy flying!