AD Amdt-39-10947

final rule
Data completeness: 70%

Airworthiness Directives; Rolls-Royce Limited, Bristol Engines Division, Viper Models Mk.521 and Mk.522 Turbojet Engines

AD Number
Amdt-39-10947
Status
final_rule
Effective Date
Product Category
engine
Docket
Docket No. 98-ANE-01-AD
FR Citation
63 FR 70001

Applicability

TypeManufacturerModelDetails
engine Rolls-Royce Limited Airworthiness Directives; Rolls-Royce Limited, Bristol Engines Division, Viper Models Mk.521 and Mk.522 Turbojet Engines

Unsafe Condition

Reports of high pressure (HP) fuel pump drive shaft failures resulting in in-flight engine shutdowns, attributed to reduced lubricity properties of fuel caused by water contamination.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Remove from service affected HP fuel pumps and replace with serviceable HP fuel pumps, as specified in Rolls-Royce Service Bulletins 73-A115 and 73-A118, depending on engine model and part number.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 18 months after the effective date of the AD, or earlier as specified.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Rolls-Royce Limited, Bristol Engines Division, Viper Models Mk.521 and Mk.522 turbojet engines with specific HP fuel pump part numbers (MGBB.167, MGBB.134, MGBB.137, MGBB.145, MGBB.168, MGBB.169).

AI-generated summary from the source AD text. Verify against the official source before acting.

Source: Official FAA Source ↗

Retrieved: Apr 6, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.