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66-04-03: Main Rotor Blades

FAA order 66-04-03 is an airworthiness directive in force since April 27, 1976. The FAA's subject line: Main Rotor Blades. It names Sikorsky S-55: about 15 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: rotorcraft systems.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
Orlando Helicopter Airways, Inc.; Sikorsky Aircraft Corporation
Models
HRS-1/CH-19, HRS-3/H-19B, S-55, S-55B, S-55C, S62A
On this site
Sikorsky S-55 15 registered

Dates and paperwork

In force since
April 27, 1976
Docket
Unknown
Status
Current
The FAA's document
Read the order on the FAA's site

The order itself the regulatory text, as published

Show the full text (2,003 characters)
66-04-03 SIKORSKY: Amdt. 39-194 Part 39 Federal Register February 12, 1966, as amended by Amendment 39-1563 is further amended by Amendment 39-2577. Applies to Models S-55 Series and S-62A Helicopters. Compliance required as indicated. To prevent operation with fatigue cracks in the spar of a main rotor blade, accomplish the following: (a) Except as provided in (e), remove from service S14-10-2100 series main rotor blades with 2,225 or more hours' time in service on the effective date of this AD within the next 25 hours' time in service. (b) Except as provided in (e), remove from service S14-10-2100 series main rotor blades with less than 2,225 hours' time in service on the effective date of this AD before the accumulation of 2,250 hours' time in service. (c) Except as provided in (e), remove from service S14-10-2201 series main rotor blades with 2,100 or more hours' time in service on the effective date of this AD within the next 150 hours' time in service. (d) Except as provided in (e), remove from service S14-10-2201 series main rotor blades with less than 2,100 hours' time in service on the effective date of this AD before the accumulation of 2,250 hours' time in service. (e) The service life limits specified in (a), (b), (c), and (d) may be extended to 6,000 hours' total time in service for S14-10-2201-9 main rotor blades and S14-10-2100 series and S14- 10-2201 series blades modified to S14-10-2201-9 blades, provided the blades are inspected at the times and in the manner set forth in Sikorsky Service Bulletin No. 55B10-7E dated March 26, 1976 or No. 62B10-6E dated March 26, 1976 or later FAA approved revisions, as applicable, and, if low pressure is indicated, the cause is determined and corrected before further flight in accordance with the applicable service bulletin. Amendment 39-194 became effective February 12, 1966. Amendment 39-1563 became effective November 30, 1972. This Amendment 39-2577 becomeseffective April 27, 1976.

Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 9, 2026. Connections as data: /graph/directive/66-04-03.json · aircraft systems.