SAIB SW-06-55 —

1 SPECIAL AIRWORTHINESS INFORMATION BULLETIN

Aircraft Certification Service Washington, DC

U.S. Department of Transportation Federal Aviation Administration

SW-06-55 July 13, 2006 http://www.faa.gov/aircraft/safety/alerts/SAIB This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) alerts you, owners and operators of Robinson Helicopter Company (RHC) Models R22 and R44 helicopters, that a small disbond may occur between the tip of the inboard doublers and the skin on the stainless steel type main rotor blades. RHC has issued two service letters that pertain to this condition. Both are available on the company web site at www.robinsonheli.com. This SAIB applies to all RHC Model R22 and R44 helicopters with main rotor blades, part number (P/N) A016-4, C016-2 or C016-5.

Background

The current Model R22 helicopter’s main rotor blade, P/N A016-4, has been changed from an aluminum skin to a stainless steel skin similar to those on the Model R44 helicopters. Several of the Model R22 A016-4 blades have been found disbonded at the outboard tips of the inboard doubler. Similar disbonds are also occurring on the Model R44 blades, P/Ns C016-2 and C016-5. This disbonded condition, when it is within the limits specified in the Service Letters, does not pose a hazard to safe flight. Recommendations

The service information should be followed to prevent the disbonds from growing beyond limits.

For the Model R22 helicopter, we recommend performing a tap inspection on the A016-4 main rotor blade at the outboard tips of the A934 doubler as described in R22 Robinson Service Letter SL-55. Repeat the inspection at each 100-hour inspection of the helicopter. If disbond is found beyond the limits, notify RHC per the Service Letter.

For the Model R44 helicopter, we recommend performance of a tap inspection on the C016-2 or C016-5 main rotor blade at the outboard tips of the C934 doubler as described in R44 Robinson Service Letter SL-31. Repeat the inspection at each 100-hour inspection of the helicopter. If disbond is found beyond the limits, notify RHC per the Service Letter.

For Further Information Contact

Mr. Fred Guerin, Aerospace Engineer Los Angeles Aircraft Certification Office 3960 Paramount Boulevard Lakewood, California 90712; phone: (562) 627-5232; fax: (562) 627-5210; email: [email protected].