StacksVerified U.S. regulatory reference

14 CFR §29.659

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
  1. (a)The rotor and blades must be mass balanced as necessary to—
    1. (1)Prevent excessive vibration; and
    2. (2)Prevent flutter at any speed up to the maximum forward speed.
  2. (b)The structural integrity of the mass balance installation must be substantiated.