The Nights Can Still Be Cold: The Avionics Warm-up

You’ve probably already read my call to watch your tires and preheat your engine when the temperature gets cold. Now I’m going to remind you about another important part of your flying that needs a little time to warm up on those spring mornings (and most any other day) – namely, your Avionics! The key here is to remember that aircraft are generally built for transportation over large distances. (Translation: just because the nights are warm where you came from, that doesn’t mean they’ll be warm where you’re going.) As a pilot you must be very aware of your surroundings — more so than you are attached to your expectations.

Truth to be told, most of the time they will – avionics are designed to work in a wide array of temperatures, that range from the almost insanely high to the terribly cold. BUT… That said, your avionics could use a little time to warm up before you launch skyward. Here’s why…

Have you every seen your avionics “glitch” when it is cold? Whether it is your fuel computer cycling back to the “power up” mode after you press the button to make it ready, or your new MFD screen seeming to go in slow motion. More and more modern avionics need decent cabin temperatures to operate at their peak level of efficiency. This may take only a few minutes of engine time, but will work wonders toward making your avionics “behave” as you expect them to — providing accurate time-sensitive information.

Not much at all. But there is a better method than turning the key and turning skyward.

  1. Start your engine, and (if the cabin is cold) make sure you turn the heat on.
  2. Check out all your engine gauges for a minute – is the oil pressure okay? How about the ammeter – has it returned to where you expect it to reside?
  3. THEN, flip the avionics master.

In the winter, when it’s 20 degrees outside give your engine a chance to warm up, and in doing so, drive some warmer air into the cockpit. Have the avionics turned on while everything else warms up, since the avionics typically generate some heat, and will help to “auto-warm” to a degree. But in the spring, you can still experience a night frost in many areas of the country — and especially in higher elevations.

Cockpit Preheat. This takes a good space heater, but while you preflight your plane, you can have the space heater preheating your cockpit. This approach has two advantages: first, it makes the cockpit more comfortable to sit and fly in, and second, it makes the avionics work much better. If you use this approach, take care to point the heater’s discharge away from any plastics (windows, avionics, interior panels) … THEY MAY MELT!

Suspicious Observation. As you taxi out to the holding area for your runup, watch your avionics. Are they responding as you would expect, or are they still a bit behind? If the avionics are slow to respond, give them a few more minutes, which is even more important if you are thinking of departing IFR! Finally, if your avionics refuse to play nice, play it safe and either wait longer for them to warm up, or call it a day!

THE BOTTOM LINE: There is no rocket science to this, but by allowing your avionics to warm up, or even preheating your cockpit you will make sure that all of the parts of your airplane are ready and able to participate in your planned flight. While this may seem like an inconvenience, it is nowhere near as inconvenient as having one of your avionics take an unannounced trip to the land of dysfunctional instrumentation while you are launching into the morning fog. Take the time to warm up your gear!