AD/B767/72 - Static Inverter Replacement (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

Boeing 767 Series Aeroplanes

AD/B767/72 Static Inverter Replacement 10/93

Applicability: All model 767 series aircraft identified in Boeing Alert Service Bulletin 767-24A0085 dated 17 September 1992.

Requirement: 1. Inspect the static inverter to determine the part number in accordance with Boeing Alert Service Bulletin 767-24A0085 dated 17 September 1992.

If Boeing Part Number S282T004-7 appears on the static inverter, then prior to further flight, replace the static inverter with an improved model and perform an operational test in accordance with the Boeing alert service bulletin.

2. Static inverters, part number S282T004-7, may not be fitted as replacements in Boeing 767 series aircraft. Existing installations of part number S282T004-7 may remain in service until Requirement 1 is accomplished.

Note: FAA AD 93-13-01 Amdt 39-8614 refers.

Compliance: Requirement 1 - Unless previously accomplished, prior to 16 September 1994.

Requirement 2 - With effect 16 September 1993.

Background: The FAA has received several reports of the loss of 115 volt AC electrical power to the standby bus during ground power transfer operations. Laboratory tests have confirmed that the static inverter S282T004-7 can shutdown during power transfer.

Compliance with this Directive is intended to prevent shutdown of the static inverter during power transfer, which could result in the inability to restart the engines in the event of a dual engine flameout. The FAA compliance time is extended by approximately one month.