| AD Number | 79-25-08 | Status | Active |
| Effective Date | Not specified | Issue Date | Not specified |
| Docket Number | Unknown | Amendment | 39-3635 |
| Product Type | ["Aircraft"] | Product Subtype | ["Rotorcraft"] |
| CFR Part | --- - Part 39 | CFR Section | N/A |
| Citation | This information is not available. | ||
| Manufacturer(s) | Sikorsky Aircraft Corporation |
| Model(s) | S-76A |
79-25-08 SIKORSKY AIRCRAFT DIVISION: Amendment 39-3635. Applies to all Model S-76A helicopters equipped with Sikorsky Models 76650-09802-101 and 76650-09802-102 hydraulic pumps.
Compliance required as indicated, unless previously accomplished.
To check the operation of existing installed pumps and to replace all defective pumps, accomplish the following:
1. If a hydraulic pump is known to have operated after fluid had been lost from the system, it is likely that the pump has run dry and it must be replaced prior to further flight.
2. If hydraulic fluid has been lost from a hydraulic reservoir, but the system has not run dry, perform servicing and bleeding procedures in accordance with the S-76A maintenance manual prior to further flight.
3. During each rotor startup, check for hydraulic pressure indication in the green arc range at 60% NR. The check required by the aforementioned sentence may be performed by the pilot. If hydraulic pressure is not in thisrange, conduct trouble shooting procedures and replace any malfunctioning component prior to further flight.
4 (A). Replace all hydraulic pumps, Sikorsky P/Ns 76650-09802-101 and 76650-09802-102, with Sikorsky P/N 76650-09802-103, in accordance with Paragraphs 4(B) and 4(C) below. These approved replacement pumps may also be identified by the suffix "C" after the serial number.
(B). For pumps with 250 or more hours time in service on the effective date of this AD, compliance with paragraph 4(A) is required within the next 100 hours time in service.
(C). For pumps with less than 250 hours time in service on the effective date of this AD, compliance with Paragraph 4(A) is required before the accumulation of 350 hours time in service.
NOTE: Sikorsky Commercial Customer Service Notice 76-16, dated November 14, 1979, applies to this AD.
The manufacturer's Customer Service Notice and Maintenance Manual identified and described in this directive are incorporatedherein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to S-76A Product Manager, Commercial Customer Service Department, Sikorsky Aircraft Division, North Main Street, Stratford, Connecticut 06602. These documents may also be examined at Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803 and FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. 20591.
This amendment becomes effective upon publication in the Federal Register, except for recipients of the Emergency AD, dated November 16, 1979, for whom it became effective upon receipt.