90-23-03: Main Rotor Servo Control

90-23-03 AEROSPATIALE (SOCIETE NATIONALE INDUSTRIELLE AEROSPATIALE): Amendment 39-6777. Docket No. 89-ASW-66. Applicability: Model AS 350 and AS 355 series helicopters, with Dunlop main rotor servo controls, part numbers (P/N) AC 64182, AC 67030, AC 66442, and AC 67034 installed. Compliance: Required as indicated, unless already accomplished. To prevent failure or malfunction of the main rotor servo controls due to icing, which could result in loss of control of the helicopter, accomplish the following: (a) Within the next 300 hours' time in service, install a protective cover on each main rotor servo control in accordance with the Accomplishment Instructions of Aerospatiale Service Bulletin No. 67.11, dated March 23, 1989, or 67.14, dated April 18, 1990, as applicable. (b) An alternate method of compliance or adjustment of the compliance times, which provides an equivalent level of safety, may be used if approved by the Manager, Rotorcraft Standards Staff, ASW-110, Rotorcraft Directorate, Aircraft Certification Service, Fort Worth, Texas 76193-0110. The installation procedures shall be done in accordance with Aerospatiale Service Bulletin No. 67.11, dated March 23, 1989, or 67.14, dated April 18, 1990, as applicable. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Aerospatiale Helicopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 75053-4005. Copies may be inspected at the Rules Docket in the Office of the Assistant Chief Counsel, FAA, 4400 Blue Mound Road, Bldg. 3B, Room 158, Fort Worth, Texas, or at the Office of the Federal Register, 1100 L Street, N.W., Room 8301, Washington, DC. This amendment (39-6777, AD 90-23-03) becomes effective on December 3, 1990.