SAIB SW-06-36 —

SW-06-36 April 4, 2006 http://www.faa.gov/aircraft/safety/alerts/SAIB This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin alerts you, owners and operators of Sikorsky Aircraft Corporation, Model S-70 series rotorcraft, to inspect the Access Doors and Quick Release Hinge Assemblies used in several component assemblies.

Background

There have been several occurrences of the APU access door detaching and causing damage to the aircraft. Investigations on failed access door hinges have found fatigue cracks. Most of these incidents occurred on the U.S. Army UH-60, which the S-70 is based on. The Army issued new sections in TM 1-1520- 237-PMD to provide daily inspections to prevent these detachments. Also, Sikorsky has issued an Alert Service Bulletin (ASB) No. 70- 02-32, to inspect the Hartwell Quick Release Hinge Assembly to prevent an alternate failure mode that can lead to access door detachment.

Recommendation

We recommend the following daily inspections:

• Inspect oil cooler access doors for loose or missing fasteners, particularly at the door hinges. Inspect hinges on airframe and door for cracks, wear, and security. Inspect latch mechanisms for worn or loose pins. • Inspect APU access doors for loose and missing fasteners, particularly at the door hinges and the center beam. Inspect latch mechanisms for cracks, wear, and security. Inspect latch mechanisms for worn or loose pins. Inspect hinges on airframe and door for cracks, wear, and security.

• Replace any cracked or worn parts.

We recommend the following one-time inspection:

• Inspect the Hartwell Quick Release Hinge Assembly and replace any failed parts per the instructions provided in Sikorsky ASB 70-02-32.

For Further Information Contact

Jeffrey Lee, Aviation Safety Engineer, FAA Boston Aircraft Certification Office, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238-7161; fax: (781) 238-7170; email: [email protected]

For Service Information Contact

Sikorsky Aircraft Corporation, 6900 Main Street, P.O. Box 9729, Stratford, CT 06615; phone: (800) 946-4337 or (203) 416-4299; fax: (860) 998-7556; email: [email protected]