mikeash.com pyblog/friday-qa-2015-09-18-building-a-gear-warning-system.html comments

DustinDawind - 2026-03-31 04:24:11

Tue, 31 Mar 2026 04:24:11 GMT

I realize this is an old post, but I just came across it as I am working on getting a gear warning system installed in my glider. Having watched a YouTube video where the pilot's gear warning system was a lady's hair clip, I thought there has to be a better way. The YouTuber's system was quite janky and worked like this: clip it on the spoiler handle before take off. Then when getting ready to land put the gear up and move it from the spoiler handle to the gear handle. That way if you go to pull the spoilers and the hair clip is in the way that will alert you to check the gear.

Anyway I found a kit for a gear alarm on Wings and Wheels for about $50.00. I'm sure it could be done for cheaper, but I'm too lazy to go figure out what parts to buy and source them all when I can just buy it all at once. But your comment about a hardware failure is a really good point. I would not want to have to land because of a stupid buzzer that won't shut off. But I don't really want to figure out all that coding of a microcontroller. So I think I will just put a toggle switch in the panel. The idea would be just leave it in the on position as the default. The kit comes with a push button to be used to test the buzzer. So during the pre take off checklist you press the button to verify that the alarm is on and working. If the system would fail in flight causing the buzzer to turn on continuously, just flip the toggle switch to shut it off and worry about it after the flight. Of course the system would not be meant to replace checking the gear as part of the pre landing checklist.

Andrew Small - 2015-11-27 16:23:15

Fri, 27 Nov 2015 16:23:15 GMT

Do you leave it in for your co-shareholders to use?

mikeash - 2015-10-21 20:07:41

Wed, 21 Oct 2015 20:07:41 GMT

I forgot to add: I'll see if I can make a recording of the buzzer at the next opportunity, but it might be a few more weeks!

mikeash - 2015-10-21 16:00:18

Wed, 21 Oct 2015 16:00:18 GMT

You guys are funny. Just traveling, and I'm back now and hope to get back in the routine soon. Probably not this week, but aiming for next week.

I know you're joking, but just to take it seriously for a moment, this isn't really a safety system. Landing gear-up is slightly more dangerous, but it still takes a lot of effort to get yourself killed or seriously injured doing it. Plus, any safety impact is strictly zero or positive, since the default is not to have a warning system at all.

There is a slight risk from the hardware, since theoretically it could start an electrical fire. But microcontroller handles the power conversion and the stuff I hook up to is limited to something like 40mA, so not much can go wrong there. And of course I installed the unit with a fuse.

I don't trust myself to build anything actually safety-critical!

Henry Skoglund - 2015-10-20 18:24:00

Tue, 20 Oct 2015 18:24:00 GMT

@Simon: read the quick note at the end, no worries!

Simon - 2015-10-19 15:13:46

Mon, 19 Oct 2015 15:13:46 GMT

Is anyone else concerned that Mike's last post was over a month ago, was atypical of him, and was about DIY'ing a safety-critical system in a pushing-the-envelope unpowered, single-pilot aeroplane ? [grin]

Mike Akers - 2015-10-09 18:04:28

Fri, 09 Oct 2015 18:04:28 GMT

Got any recordings of the buzzer patterns?

Alan - 2015-10-09 08:54:51

Fri, 09 Oct 2015 08:54:51 GMT

This article made my day. It's always fun to read about other people's experiences when it comes to human creativity. Great article!

Matthew Elton - 2015-09-19 09:11:25

Sat, 19 Sep 2015 09:11:25 GMT

I very much enjoyed this article. It reminded me of building some hardware on veroboard and handwriting 6502 code to drive it so that my 1980s era home micro could talk to an inherited teletype. I had no idea you could buy something like this Digispark gizmo and for so little money. Thanks for the post.