StacksVerified U.S. regulatory reference

14 CFR §121.239

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov
  1. (a)Each oil valve must—
    1. (1)Comply with § 121.257;
    2. (2)Have positive stops or suitable index provisions in the “on” and “off” positions; and
    3. (3)Be supported so that loads resulting from its operation or from accelerated flight conditions are not transmitted to the lines attached to the valve.
  2. (b)The closing of an oil shutoff means must not prevent feathering the propeller, unless equivalent safety provisions are incorporated.