by Zach Grant L1011jock » Mon Jun 21, 2010 2:30 am
John,
It could be the horn, but I doubt it. The horn is under the panel, most likely attached to the firewall (looks like a round grey box with a circular cover on the end held on with a single center screw, like a small scale air cleaner housing from a golden era muscle car...). This horn is actuated when one or both throttles are reduced below the second micro switch in the throttle quadrent (first flashes the gear up light) and that throttle position should equate to about 14" mp if set up right.
The important part here is that the nose gear down limit switch is the only one that the horn looks at. All three limit switches must make to turn on the green, but only the nose must make to keep the horn from blowing, a fail safe of sorts incase you don't get a green, if the nose is down, by default all the rest are down or you are having a very bad day.
I would bet dollars to doughnuts that the nose gear switch is bad, or you have a bad wire harness, and the horn and gear down circuit thinks the nose gear is down all the time. Start there. The wireing diagrams are in the service manual under technical on the main Comancheflyer.com page. Good luck.
-Zach
"Keep it above 5 feet and don't do nuthin dumb!"