14 CFR · Part 27
14 CFR § 27.907
Engine vibration.
(a)
Each engine must be installed to prevent the harmful vibration of any part of the engine or rotorcraft.
(b)
The addition of the rotor and the rotor drive system to the engine may not subject the principal rotating parts of the engine to excessive vibration stresses. This must be shown by a vibration investigation.
(c)
No part of the rotor drive system may be subjected to excessive vibration stresses.
Reflects the eCFR edition current as of September 29, 2026. Retrieved from ecfr.gov on October 16, 2026.
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