Glen Davis Posted August 28, 2023 Report Posted August 28, 2023 My J has flat spots on both mains. AP says they are airworthy. Will the flat spot go away? Will it thump while taxing? Quote
KSMooniac Posted August 28, 2023 Report Posted August 28, 2023 if by flat you mean there are spots abraded so much that that any groove in the tread is gone for a portion of the tire, then no, they will not go away. They might compromise traction on a wet runway, and there is of course less material to absorb the forces from landing. I don't know what the official guidance relative to replacing them might be just for a flat spot. Quote
1980Mooney Posted August 29, 2023 Report Posted August 29, 2023 17 minutes ago, Glen Davis said: My J has flat spots on both mains. AP says they are airworthy. Will the flat spot go away? Will it thump while taxing? If you occasionally land fast, land on short runways and/or are heavy on the brakes, you may have a tendency to occasionally lock the brakes. This can also happen if you are landing hot, bounce just a little but keep the brakes applied while you pop up into the air - they could be momentarily locked as you touch down on the runway the second time. These can all cause a flat spot. In this case, you will be adding new "flat spots" over time. They will randomly be in different places and you will just wear the tire down faster than normal. Until you wear down and lose the water/rain grooves or see bare cord, don't worry about it. BTW - you will never feel it. Quote
Ragsf15e Posted August 29, 2023 Report Posted August 29, 2023 (edited) A while back, @PT20J posted Goodyears aircraft tire guidance. It was very detailed with pictures and tires not showing coords were fine. Might want to take a look at it if you can find it. Edited August 29, 2023 by Ragsf15e 1 Quote
EricJ Posted August 29, 2023 Report Posted August 29, 2023 41 minutes ago, Glen Davis said: My J has flat spots on both mains. AP says they are airworthy. Will the flat spot go away? Will it thump while taxing? They generally won't go away. Whether or not they thump or vibrate seems to depend on the construction of the tire. I've had a big flat spot on one of my Goodyear Flight Custom III main gear tires for a long time and you'd never know it if you didn't see it. Some tire constructions seem susceptible to vibration with flat spots, though, so it seems to depend on that. 2 Quote
PT20J Posted August 29, 2023 Report Posted August 29, 2023 Lots of good info here https://www.goodyearaviation.com/resources/tiredatabook.html 3 1 Quote
Pinecone Posted August 29, 2023 Report Posted August 29, 2023 11 hours ago, 1980Mooney said: They will randomly be in different places and you will just wear the tire down faster than normal. Actually they typically are not random. If you are braking near the limit, when the flat spot rotates to be in contact with the pavement, it takes more force to rotate the flat spot away. So the tire will tend to lock and make the flat spot bigger. If the flat spot gets big enough (newer tire), it can thump when taxiing, but I am not sure you will notice. As long as there are no cords showing, the tire is usable. 1 Quote
A64Pilot Posted August 29, 2023 Report Posted August 29, 2023 My Mooney came with two flat spots on each main, they of course come from someone over braking determined to make a turn off. I ignored them, they will sort of go away as the tire wears down to the level of the flat spot, if you don’t over brake again anyway. I didn’t replace the tires until they were worn pretty much out. The flat spot didn’t seem to wear or if the did not as much as the rest of the tire. If they thump taxiing then you need to decide if the thump is annoying enough to replace them, I don’t think other than being annoying the thump does any harm. Mooney’s are way more susceptible than say Cessna’s, so don’t feel bad, your not the first and won’t be the last. 1 Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.