Gear alignment question (toe-in, camber, etc)

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Gear alignment question (toe-in, camber, etc)

Post by 8451 »

I was out flying yesterday and landed at an airport where I saw another 120 parked in a shade hangar. I of course wandered over to inspect it and I noticed the gear was aligned differently than my airplane; the most noticeable was significantly different camber angle on the wheels.

It gets me to wondering - is something wrong with either my wheel alignment or gear legs? Do I need shims on my axles? Anything else I’m not considering?

I’ve attached pictures of the airplane I saw as well as mine.
The other airplane
The other airplane
D0114AB6-376E-461C-8D98-547E9DAEC15E.jpeg (245.93 KiB) Viewed 3715 times
My airplane
My airplane
9179C709-EFBD-4248-992F-6350D2DF82C8.jpeg (254.64 KiB) Viewed 3715 times
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Re: Gear alignment question (toe-in, camber, etc)

Post by 2356 »

My plane looks like the upper photo.
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6643
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Re: Gear alignment question (toe-in, camber, etc)

Post by 6643 »

I think if you lay a straightedge along your gear legs you'll find they are slightly bowed. I'm not sure it's anything to be concerned about, though. However, it looks like your tires are wearing a little on the outside. If so, you might want to reduce the toe-in slightly.
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Re: Gear alignment question (toe-in, camber, etc)

Post by 6277 »

Sometimes tire pressures, gross weight at the time, can influence gear leg and perceived angles?
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Re: Gear alignment question (toe-in, camber, etc)

Post by 8424 »

Did you roll your plane backward just prior to taking the photo?

With a little toe in, rolling the plane backwards would spread your gear and could bow the gear a little. On a really smooth hangar floor you can hear the tires scrubbing/squealing real quietly when doing this. (I'd have to turn up the volume on my hearing aids these days to hear it!)

Roll your plane forward several feet and see if the bow disappears.

Just a thought!

Steve H
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Re: Gear alignment question (toe-in, camber, etc)

Post by 6643 »

Here's what mine looked like yesterday. We had some 50+mph winds a while back , right on its nose, and I suspect it lifted up enough to let the gear come together then dropped back down like this. Need to dig it out, untie it, and roll it around a little... (Actually, need to get the plane I'm working on out of my hangar!)
KIMG4418.jpg
KIMG4418.jpg (306.9 KiB) Viewed 3610 times
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Re: Gear alignment question (toe-in, camber, etc)

Post by 8451 »

Thanks for the input. I’ll roll it around and see if that alleviates the perceived issue. If not I was planning to jack it up during annual in March anyway so that would be a good opportunity to play with the shims and compensate for any bowing of the legs if necessary.
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Re: Gear alignment question (toe-in, camber, etc)

Post by 6643 »

If, as it appears from your tire wear, your tires are toed in, then, if you roll it backwards your gear will splay outwards like in the photo. So, did you push the plane backwards before you took the photo?
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Re: Gear alignment question (toe-in, camber, etc)

Post by 8451 »

I went out to the hangar after the posts here and rolled the plane forward and observed the gear. It does appear the gear is slightly bowed still. The left wheel did exhibit a slight camber with the top of the wheel pointing out, while the right appeared to be straight up and down.
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Re: Gear alignment question (toe-in, camber, etc)

Post by 8342 »

If you are not having any issues with take off and landings, I am of the mind to leave it alone.

If it aint broke don't fix it.

If the tires are wearing one side more than the other. Rotate them on the rim to even it out.
We did that for year at the FBO I turned wrenches at.

Rick
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