Safety Advisory Notice SAN19960157

Safety Advisory Notice issued to: Civil Aviation Safety Authority

Recommendation details
Output No: SAN19960157
Date issued: 03 October 1997
Safety action status: Closed

Appropriate Maintenance Release procedures for the continuing airworthiness of class A aircraft.

The class A aircraft was engaged in a night training exercise at Tamworth with three pilots on board. After takeoff from runway 12L, the aircraft diverged left and struck trees and powerlines before impacting the ground in a semi-inverted attitude. The crew had simulated the failure of the left engine shortly after reaching the take-off decision speed (V1).

A defect with the nosewheel steering may have added to the pilot's work load on the final takeoff. This defect was entered on the Maintenance Release by a pilot 13 days before the accident flight. The pilot cleared the endorsement on the Maintenance Release as "not a major defect", and transferred the defect to the Deferred Defect List.

The Civil Aviation Safety Authority approves Maintenance Control Manuals that allow pilots of class A aircraft to:

(a) endorse a Maintenance Release clearing a defect as not major without certification; and

(b) transfer those defects to the Deferred Defect List.

These actions can result in a defect being inappropriately assessed and left unactioned.

The operator's approved procedures in the Maintenance Control Manual state, "To transfer an endorsement, where facilities are not available to rectify the damage or defect, the pilot in command or an appropriate Licensed Aircraft Maintenance Engineer engaged in the maintenance of the aircraft shall:

(a) consult the operators Minimum Equipment List for the aircraft to determine that the damage or defect can be transferred to the Deferred Defect List;

(b) if not included in the applicable operators Minimum Equipment List, determine that the damage or defect is not of such a kind that it may affect the safety of the aircraft or cause the aircraft to become a danger to persons or property and therefore is not major damage / defect (NMD), and is not an instrument or equipment required by Civil Aviation Order 20-18 subsection 10.

NOTE : The Pilot-in-command may need to consult with an appropriately Licensed Aircraft Maintenance Engineer to make determination (b) above."

Currently the regulatory requirement applicable to defects and the endorsement of the Maintenance Release, is as follows: Civil Aviation Regulation 50 requires defects to be endorsed on a Maintenance Release and, if the defect or damage is considered to be "major", then a Civil Aviation Regulation 47 endorsement declaring the aircraft to be unairworthy may be required. In contrast, "not-major" defects may be carried for the duration of the Maintenance Release as open defects. These defects are entered on the Maintenance Release for the pilot's notification and decision as to whether or not to fly with the open defect. However, in this occurrence, the pilot transferred the defect to the Deferred Defect List as "not a major defect".

This Deferred Defect list is approved as part of the Maintenance Release, and the defect was still open at the time of the accident. There was no indication that any pilot had re-assessed the defect, or required corrective action be taken in the intervening period.

A survey of some regional operators has confirmed that this procedure is not isolated. Many regional operators have approved Maintenance Control Manuals which incorporate similar procedures.

With the complexities of the modern high-technology transport category aircraft, all defects cleared on the maintenance release as "not a major defect" should be certified by an appropriate licensed aircraft maintenance engineer before transfer to the Deferred Defect list. This is the approved procedure of the major domestic airlines.

Output text

The Civil Aviation Safety Authority should take note of this deficiency, and take appropriate action.

Initial response
Date issued:
Response from: Civil Aviation Safety Authority
Action status: Not Required
Response text:
Last update 01 April 2011