SAIB SW-05-20 —

1 SPECIAL AIRWORTHINESS INFORMATION BULLETIN

Aircraft Certification Service Washington, DC

U.S. Department of Transportation Federal Aviation Administration

SW-05-20 December 2, 2004 www.faa.gov/certification/aircraft This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin alerts you, owners and operators of all Eurocopter France models AS-350 and AS 355 rotorcraft that have after market center console panels installed, that preliminary investigations reveal a potentially hazardous situation in which the collective lock strip inadvertently engages during flight maneuvers, locking the collective in the down position.

Background

There were two accidents involving the AS- 350 series rotorcraft where the pilots reported that during training, when the collective was lowered, the collective lock, P/N 350A27- 3107-26, inadvertently engaged. This prevented the collective from being raised to arrest the descent, resulting in subsequent impact with the terrain. The impact resulted in both rotorcraft being destroyed. Examination of other rotorcraft with the after market center console panel installed revealed the position of the collective lock strip, P/N 350A27-3107-26, and the collective lock knob, P/N 350A77- 1309-24, were extremely close, approximately 2 mm. Additional information on the two accidents can be provided by Patrick Jones, Air Safety Investigator, National Transportation Safety Board, email: [email protected], phone: 310-380- 5657.

Recommendations

• Inspect the condition of the collective locking strip, P/N 350A27-3107-26, to ensure the strip has a positive spring force to hold it away from the collective knob and firmly against the center console. Inspect and ensure the rubber grommet, P/N 85007-130-015, is resting against the center console.

• To ensure proper rigging of the collective, review AS-350 collective lock rigging procedures, Work Card 67.10.00.501 without autopilot and Work Card 67.10.00.502 with autopilot.

• Ensure that there is a positive clearance (nominally 7mm) between the collective lock knob, P/N 350A77-1309-24, and the collective strip.

• Ensure the aftermarket installation is installed as to allow proper clearance for the collective lock at all times.

• We believe that there may be other non- reported incidents of this occurrence from the field, so, in order to determine the scope of this issue, if you have experienced this inadvertent locking of the collective and recovered without incident PLEASE report it to the FAA Contact listed below.

• Ensure the collective lock spring mounting bolts are secure and torque properly, 35-44 in. lb.

2 For Further Information Contact

Gary Roach, Aerospace Engineer, FAA Rotorcraft Directorate, ASW-111 Rotorcraft Standards Staff, Fort Worth, Texas 76193- 0110; phone: (817) 222-5130; fax: (817) 222- 5961; E-mail: [email protected].