SAIB SW-12-23

FAA Aviation Safety

SPECIAL AIRWORTHINESS

INFORMATION BULLETIN SAIB: SW-12-23 SUBJ: Sikorsky Aircraft Corporation Model S92A Fuselage – Cabin Airframe Inspection Date: March 29, 2012 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) alerts owners and operators of Sikorsky Aircraft Corporation (Sikorsky) S-92A helicopters to follow the current Sikorsky Alert Service Bulletin (ASB) No. 92-53-007. At this time, the airworthiness concern is not an unsafe condition that would warrant airworthiness directive (AD) action under Title 14 of the Code of Federal Aviation Regulations (14 CFR) part 39.

Background

Sikorsky issued Sikorsky ASB No. 92-53-007, dated March 30, 2011 (ASB No. 92-53-007) and Temporary Revision (T-Rev) No. 53-11, dated April 4, 2011. This ASB for the Sikorsky S92A helicopters (S92A) with greater than 2,500 flight hours implements a recurring visual inspection of cabin structure at STA 328 and STA 361 for cracks. To date, two cracks have been found at cabin structure location STA 361. Sikorsky has determined that similar cabin structure at STA328 should be examined for cracks as well. The T-Rev adds a corrected inspection procedure for cabin frame assemblies to the S92A Aircraft Maintenance Manual (AMM).

Sikorsky has also issued Special Service Instructions SSI No. 92-037B, dated January 5, 2011, which modifies certain cabin frame assemblies. Accomplishing these modifications per SSI No. 92-037B eliminates the need for the recurring visual inspection identified in ASB No. 92-53-007.

Recommendations

For all S-92A model helicopters with 2,500 flight hours or more prior to March 30, 2011 that have not complied with Sikorsky Special Service Instructions (SSI) 92-037 (latest revision), which provides instructions for modifying the cabin structure at STA 328 and STA 361, we recommend performing the 100 hour recurring visual inspection of cabin structure at STA 328 and STA 361 for cracks per Sikorsky ASB No. 92-53-007. Performance of Sikorsky Special Service Instructions (SSI) 92-037 (latest revision) eliminates the need for this recurring visual inspection identified in ASB No. 92-53-

007.

For Further Information Contact

Nicholas Faust, Aerospace Engineer, Boston Aircraft Certification Office, ANE-150; phone: (781) 238-7763; fax: (781) 238-7170; e-mail: nicholas.faust@faa.gov.

For Related Service Information Contact

Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical Support, mailstop s581a, 6900 Main Street, Stratford, CT, telephone (203) 383-4866, e-mail address tsslibrary@sikorsky.com, or at http://www.sikorsky.com.