(a) Each airspeed indicator must be marked as specified in paragraph (b) of this section, with the marks located at the corresponding indicated airspeeds.
(b) The following markings must be made:
(1) A red radial line--
(i) For rotocraft other than helicopters, at VNE; and
(ii) For helicopters at VNE (power-on).
(2) A red cross-hatched radial line at VNE (power-off) for helicopters, if VNE (power-off) is less than VNE (power-on).
(3) For the caution range, a yellow arc.
(4) For the safe operating range, a green arc. (Secs. 313(a), 601, 603, 604, and 605 of the Federal Aviation Act of 1958 (49 U.S.C. 1354(a), 1421, 1423, 1424, and 1425); and sec. 6(c) of the Dept. of Transportation Act (49 U.S.C. 1655(c))) [Doc. No. 5074, 29 FR 15695, Nov. 24, 1964, as amended by Amdt. 27-14, 43 FR 2325, Jan. 16, 1978; 43 FR 3900, Jan. 30, 1978; Amdt. 27-16, 43 FR 50599, Oct. 30, 1978]