Unless otherwise specified, a factor of safety of 1.5 must be applied to the prescribed limit load which are considered external loads on the structure. When a loading condition is prescribed in terms of ultimate loads, a factor of safety need not be applied unless otherwise specified.
[Amdt. 25-23, 35 FR 5672, Apr. 8, 1970]
source: Docket No. 5066, 29 FR 18291, Dec. 24, 1964, unless otherwise noted.
cite as: 14 CFR 25.303