Service Difficulty Advisory

AV 2003-06
10 November 2003

Israel Industries Astra SPX

Nosewheel Steering Bracket Failure

Transport Canada has learned through the Service Difficulty Reporting System that an Israel Industries Astra SPX departed the runway while attempting to land.

As the aircraft nosewheel touched down, the flight crew experienced difficulty controlling the aircraft due to a severe nosewheel shimmy. During the nosewheel shimmy, an uncommanded full left steering input was experienced and the crew was unable to maintain directional control. The aircraft veered off the runway and settled in a grassy area, sustaining minor damage to the nose gear and slight damage to the wing tip when it had contact with the ground.

Initial findings indicate the nosewheel steering upper (P/N 22249.0110.001) and lower (P/N 2249.0120.001) attachment brackets, were broken. Testing of the brackets has shown the upper bracket had previously failed, and the lower failure happened at the time of this accident. Due to the location of the upper bracket, inspection is difficult without the aircraft on jacks and the defect was not detected on the aircraft preflight. Both of these parts may have been previously damaged during towing.

Schematic of a nosewheel steering bracket

Gulfstream has produced Service Bulletin 1125-11-181 and Service Information Letter 1125-09-096, on towing procedures and limitations for the Astra.

Nosewheel steering towing limitations are often exceeded on many aircraft resulting in potential damage. Transport Canada reminds maintenance personnel and pilots of the paramount importance of briefing tow operators of these limitations. This should be done prior to the movement of the aircraft.

Any further defects or occurrences should be reported to Transport Canada, Continuing Airworthiness, Ottawa via the Service Difficulty Reporting program.

For further information contact a Transport Canada Centre, or call Mr. Steve Dudka, Continuing Airworthiness, Ottawa, telephone (613) 952-4361, facsimile (613) 996-9178 or e-mail dudkas@tc.gc.ca.

For Director, Aircraft Certification

R. William Taylor
Acting Chief, Continuing Airworthiness