Text in force at 29-59: from 29-30, effective 5 Apr 1990.
The rotorcraft must be designed for--
[(a) A limit maneuvering load factor ranging from a positive limit of 3.5 to a negative limit of -1.0; or
(b) Any positive limit maneuvering load factor not less than 2.0 and any negative limit maneuvering load factor of not less than -0.5 for which--]
(1) The probability of being exceeded is shown by analysis and flight tests to be extremely remote; and
(2) The selected values are appropriate to each weight condition between the design maximum and design minimum weights.
55 FR 8003 · Source