That all-important clock

That all-important clock - 086 - Davtron M803

That all-important clock - 086 - Davtron M803

To be legal when flying under Instrument Flight Rules (IFR) you need to have an operating clock installed on your instrument panel. It can have an analog presentation with a sweep-second hand, or be a digital clock. This sounds simple enough. But some pilots seem a bit blase about this.

The Crossover Classic’s previous owner was one such pilot. He had a clock on the panel, all right. But it had given up the ghost long ago. “Ah, that doesn’t matter. I use my wristwatch,” he kept saying. Sorry, not good enough. The regs say a clock  must be mounted on the panel. To correct the situation, the owner had an “inop” sticker placed under the clock. But that’s no good unless the airplane has an approved minimum equipment list (MEL), which it didn’t. “What’s an MEL?” the owner wanted to know.

To remedy all this, renowned aviation chronometer manufacturer Davtron kicked in with its M803 digital clock. This useful–and did I say required?–unit shows time galore. We located it at the top left of the pilot’s instrument panel, where it has served us well. I mainly use it to keep track of elapsed time between legs. Just push the right button once, and the clock starts counting up. Push it again, and it stops. Easy.

The M803 shows Zulu time, local time, flight time, and elapsed time. It also shows the electrical system voltage and outside air temperature. You use the M803’s lower two buttons to initially set your times, and the ship’s power then keeps the unit running. A backup internal battery keeps the unit running should there be a complete loss of electrical power. In this case, you’d be down to the ship’s battery for powering a (load-shedded) panel, plus the M803’s and L-3 Trilogy’s own internal battery supply (worth up to two hours of flying time, I’ve been told) if everything goes dark.

Davtron is perhaps the largest supplier of general aviation panel-mount timepieces, and for good reason: They’re durable and intuitive to use. You probably have one in the airplane you fly! And what if the M803, by some ill stroke of luck, kick the bucket? Well, there are digital clocks in the Garmin 430s abaord the Crossover Classic, as well as a clock in the Garmin GTX-330 transponder. So we have time covered in spades on this unique airplane.

  • Mark Jones Jr.

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  • Philip Smith

    So if you have a gps with a clock in the panel, would that not meet the FAA requirement?

    • brettinlj

      Wondering the same thing. So many club airplanes have a broken clock, but a Garmin 430 so want to make sure this is legal for IFR.

  • Philip Smith

    So if you have a gps with a clock in it instead of the panel, would that not meet the FAA requirement?

  • Guy Pigg

    Wow….surprise for the previous owner. Would like to know the web site for the manufacturer’s web site… guess will google and see what happens… would like to get a yoke mounted one for the various planes I fly.

  • QRP

    Might be a slight typo in the last paragraph. “…in the Garmin 430s abaord the Crossover Classic,..”
    I think the author meant “aboard”

    • thorne


      I hate laptop keybaords….


  • Mike Troici

    I will be sure to explain these features to my new flight students as soon as Craig hands me over the keys.

    • thorne

      No problemo. I’ll be there


  • Helen

    I presume you are putting a Garmin panel mount GPS in this plane? If that is the case, you don’t need this clock as the 430/530 series has a legal clock built in.

    • thorne


      It has a bunch of clocks! None of them analog I have to add

      Tom (an analog fan)

  • Mike Walsh

    Was it necessary to make the previous owner look bad? Golly, the guy provided us a good ship. Be a little more diplomatic.

    • thorne


      Point taken. But he did not maintain it to “meticulous” standards as he so often boasted


  • http://AOPAePilot Ted Sigtenhorst

    I have a Davtron digital clock in my airplane, but it is NOT mounted in the “INSTRUMENT PANEL”, it is mounted in the middle of the yoke. Is this considered to be an “INSTRUMENT PANEL MOUNTED” clock as required by the FARs???

    • thorne


      Good question. I think you’re OK but better re-read the regs…..

  • Carl Klaiber

    Interesting information presented here. So does the 430 and/or the GTX-330 serve to comply with the FAR/FAA?



    • thorne


      Oh yes. The 430 is WAAS approved and the 330 works with ATC and the 800 for traffic


  • Time me

    The reason pilot’s are blase’ about a clock is because this requirement is completely irrelevant today. We have digital timers (clocks) in how many devices on our cabin?
    – wrist watch
    – Cell phone
    – panel mount GPS
    – carry-on GPS
    – FAA Approved panel mount clock.

    Of these the panel mount GPS and handheld GPS are proven working if the GPS works, as this is how gps derives it’s location (comm time delays to/fro satellites). So these are empirically accurate and are in a sense, constantly calibrated by proof of the owrking gps reciever.

    The other sources (wrist/phone) work when the battery in the plane dies or the A/C system has a problem. And of course are unbelievably accurate.

    Thus this regulation is completely irrelevant today. It would make much more sense for the FAA to adjust the reg to “must possess a working accurate clock”. This regulation came about when wrist watches used mechanical movement to time, which can be out of calibration. The idea that a digital watch could do this is obviously ridiculous. Digital watches either work or don’t.

    • thorne

      The regs are the regs. A clock (doesn’t say what kind) must be installed…. wrist watch is a no-no


  • Allen Inks

    In my former airplane, my WX-900 Stormscope had a digital clock feature. It wasn’t as convenient to use as the clip on yoke-mounted multi-mode digital timer from Sporty’s that I actually used for flying instrument approaches, but it made me legal.

  • YK

    This blog identified the previous owner by name in one of the first posts which described the purchase. This post seems to now mock the previous owner about the clock and his knowledge of MEL.

    The previous owner was clearly wrong any way you look at it. However, this post didn’t have to embarrass him to make the point. This was a bit graceless in my opinion. One expects better from AOPA.

  • Matt

    The requirement of the clock to be panel mounted is news to me and contrary to everything every instructor or ground school has taught and my instrument examiner quizzed me on. 91.205.d.6 indicates the need for the clock with a second hand or digital representation but says nothing about being mounted to the airframe. I polled 3 instructors at our airport and they all indicated that a watch with a second hand adequately complies with the regs. Now I don’t know what to believe but this blog entry is the only thing I’ve ever read that is contrary to what everyone else in my aviation life has indicated….
    It’s a moot point to me at the moment as both aircraft that I fly have panel mounted clocks. And they work.


  • Gary

    There seems to be enough ambiguity around 92.205(d)6 that they’re just erring on the side of caution here. However, when I took my instrument oral exam, my DPE asked that question (is a panel-mounted clock required), and when I said “yes”, his response was “correct, it is required. But those things are so often inaccurate, the pilot will just use another clock, but it does have to be installed and functioning”. It does seem that the GPS-supplied clock will suffice, though.

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