Engine failure due to main bearings failure? - Page 2 - ED Forums
 


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Old 12-03-2019, 12:31 PM   #11
Yo-Yo
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Originally Posted by grafspee View Post
If engine is equipped with prop reduction gear box i think reversed thrust will not affect engine crank shaft it self but only the gear box. I think main bearings fail is due to what Yo-Yo said.
Yo-Yo will we get fatal gearbox case fail in extreme dives so we can loose prop some day ? Last i checked i climbed to 40k ft and dived straight down nothing happened
No, the main damage is exactly for the cranck shaft bearings for the reason that the plain bearings are very sensitive to the local pressure. And, by the way, for some radial engines the power-on pressure was very close to the maximal for the allowed for bearings alloy. So, any, power-off disbalance leads to overstressing.
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Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів
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Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me
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Old 12-03-2019, 12:38 PM   #12
grafspee
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Originally Posted by Yo-Yo View Post
No, the main damage is exactly for the cranck shaft bearings for the reason that the plain bearings are very sensitive to the local pressure. And, by the way, for some radial engines the power-on pressure was very close to the maximal for the allowed for bearings alloy. So, any, power-off disbalance leads to overstressing.
I was talking about forces on shaft created by prop drag, when gear box is present and prop no longer pulling or pushing crank shaft in engine case, so how this can affect crank shaft in any way.(forces parallel to crank shaft axis)
I though that main crank shaft is mounted on the rolling bearings in radial engines not plain bearings, probably im wrong about it.
German planes are the best if you cut throttle Control unit will reduce rpm problem solved
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Last edited by grafspee; 12-03-2019 at 04:27 PM.
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