Nosewheel truss damage warning device

[DonMuncy]

I was reading the nosewheel damage thread, but did not want to hijack it.

I know that in a perfect world, we would check for this damage before every flight, but I can't seem to make myself do it. Then if/when you do find damage, how do you convince the FBO their line guy did it.

I designed a device to alert you to potential damage, so one can check it when necessary.

It has two electronic buzzers. A quite loud one that sounds when the tow limit is reached (although perhaps not loud enough to be heard over the noise of a tug), that stops when the mechanism is moved back to the safe range.

However, once the tow limit is reached, it also triggers a relay which operates a much less noisy buzzer and an indicator light in the cabin, which stay on until you reset it.

So hopefully, if a lineman overdoes it, he will hear the buzzer and stop. And when you come back and find the light glowing and the buzzer going off in the plane, you know its time to carefully check for damage and report to the FBO, before you reset it and move the plane.

The unit requires mounting a small box in the cabin and a piezo buzzer under the cowl. I must admit the sensors are a real PITA to adjust. There is not a whole lot of angular movement involved. If you mis-adjust one way, it will go off anytime you turn the nose wheel at all. Too much the other way and it won't go off until damage is done.

As usual,if anyone has any interest, I'm glad to share the plans.

[jetdriven]

One thing that David McGee told us that savvy Mooney owners do is make a piece that fits in the nose gear (where the towbar goes) that locks with a padlock to prevent unauthorized towing. You could only tow it with a Lektro cart which likely wont over stress the nose gear.

[Mcstealth]

all parts available at Radio Shack?

[DonMuncy]

I'm not certain about Radio shack availability. The two piezzo buzzers and the teeny switches to trigger the alert I got from an online source, but RS may have them also.

[John Pleisse]

A few years back, I saw a gentleman who actually had a sign attached to the nose bar holes/truss. You had to look at it and remove it to tow the a/c. I can't recall the exact wording of the signage, but it was a stern civil/legal warning in bold print re: the turn limits. My truss stops have been sheared several times, all by large airport FBO's, one in particular in the NYC area. I stopped flying there over it.

[Seth]

That is a great idea. Have you come back to your aicraft with the buzzer on and the light illumniated? Does it use the ships battery? Separate power source?

I forget who it was, but there was a Mooney pilot who used to tape ketchup packets to his nose truss. If the ketchup was spattered when he got back, he'd go right to the manager of the FBO and show the proof. I have not done this, but do think about it.

-Seth

[Seth]

..

[fantom]

The ketchup packet idea is attributable to the late Norm Smith in one of his "Mooney Miser" columns in the MAPA Log back in the 80s, I believe.

Jim

Yeah, and I witnessed him using it. I think he also offered a PVC tube for the front truss with a lock on it. He, and his products, were one of a kind. RIP, Norm.

[DonMuncy]

No. Naturally, since I installed the device, no one has exceeded the limit. As far as that goes, no one ever bent the tube on my plane before I did it. We are dealing on a problem which seldom happens; but when it does, it sure ruins someone's day.

[garytex]

love the ketchup packet idea

[fantom]

Some of Norm's money saving ideas were unique, to say the least.

A tight wallet, even by Mooney standards.

But generous with everything else, and a BIG heart.