Service Difficulty Advisory

AV 1999-05
11 August 1999

Piper PA34

Tunnel Bracket

There have been three reported failures of the tunnel bracket, P/N 95554-00, which is located in the fuselage lower forward cockpit area. These failures have prompted the present Advisory to determine if this difficulty is fleet wide.

In the latest case, found as a result of an article in Feed-Back magazine issue 1/98, the operator noted that the attach point and firewall moved when force was applied. Further investigation showed that, similar to the other reported cases, the stabilizer pulley bracket was cracked and the rivets were sheared. These rivets attach the bracket and nose gear mount fitting. This failure weakens the gear drag link considerably. Airframe hours on this aircraft were 3329 TSN.

In a previous case in 1990 (3194 hr TSN) the nose gear collapsed on takeoff; in another case in 1997 (5737 hr TSN) the nose gear collapsed on landing. All three cases were found on the PA34-200T model, however this bracket is also on the -200 & -220T Models.

Schematic of the fuselage lower forward cockpit area

All the submitters indicated that this is a very difficult area to inspect unless the stabilizer pulley is removed. In addition, the nut for the gear attach bolt must be removed to see if the gear mount moves. It is possible that towing the aircraft with mechanized equipment could be the main reason for the failure.

This part can be found in the IPC at figure 12, item 14.

Discussion with Piper Aircraft indicated they were not aware of this problem, however they had sold 15 brackets with this part number over the past four years.

Any defects or further occurrences should be reported by sending a Service Difficulty Report to Transport Canada, Continuing Airworthiness, Ottawa

For more information please contact a Transport Canada Centre, or Mr. Robert Dixon, Continuing Airworthiness, Ottawa, telephone (613) 952-4308, facsimile (613) 996-9178 or e-mail dixonro@tc.gc.ca.

For Director, National Aircraft Certification

B. Goyaniuk
Chief, Continuing Airworthiness