SAIB CE-05-22 —

CE-05-22 December 17, 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 Raytheon Aircraft Company Model 390 Premier 1 airplanes (serial numbers RB-1, RB-4 through RB-15, RB-17 through RB-80, RB-82 or RB-84), of the need to inspect the elevator trim tab jack screw assembly.

Background

A condition may exist on Model 390 airplanes that could lead to loss of elevator tab function or excessive elevator tab freeplay. Raytheon discovered the condition and reported an occurrence of an untorqued cap screw in the elevator tab jack screw assembly. There are two elevator trim tab actuator screws (P/N NAS1351C4LL24) per actuator. Failures on one jack screw would likely cause a jam, which could cause a pin in the elevator trim tab system to shear. This jam would result in a loss of the elevator trim tabs with the tabs remaining in whatever position they were in when the pin sheared. The loss of one or both elevator trim tabs would not cause loss of control of the airplane but would reduce the total amount of vertical trim capability. As a result of our investigation, we suspect that the same condition may exist on other airplanes of the same type design.

Recommendation

Raytheon has released Service Bulletin (SB) 27-3646, which contains the procedures to inspect the two elevator trim tab actuator screws and to verify they are torqued to 50-70 in-lbs. We recommend that you perform the actions in the SB.

For Further Information Contact

Anthony Flores, Aerospace Engineer, FAA Wichita Aircraft Certification Office, 1801 Airport Rd, Room 100, Wichita, KS, 67209; phone: (316) 946-4174; email: [email protected]

For SB information, contact Raytheon Aircraft Company, 9709 E. Central, Wichita, Kansas 67201- 0085; telephone: (800) 429-5372 or (316) 676-3140.