CAA UK Decision not to adopt: FAA AB2023-02-02
Background
On 18 January 2023, the FAA issued AD 2023-02-02, applicable to Gulfstream Aerospace Corporation Model GV and GV-SP aeroplanes. This AD was prompted by the omission of the life limit for the main landing gear (MLG) trunnion pin, Part Number 1159SCL566-17, in the Airworthiness Limitations Section (ALS) of the Maintenance Manual.
FAA AD 2023-02-02 requires revising the ALS of the Gulfstream G550 Maintenance Manual to establish a life limit for the affected MLG trunnion pin.
Reason
During the European validation of the Gulfstream GV and GV-SP aeroplane types, a different fatigue life evaluation methodology was applied, in accordance with JAR 25.571 at that time. This resulted in some mandatory life limitations or Safe Life Limits (SLLs) for certain life limited landing gear components, which were lower than the SLLs required by FAA.
Application of the same fatigue life methodology as used during certification results in a lower SLL for the MLG pin, (P/N) 1159SCL566-17, for UK aircraft, than the life limit stated in FAA AD 2023-02-02.
Note: The CAA approved SLLs for UK registered GV and GV-SP aircraft are currently the same as the EASA SLLs published in the ALS. The intention is that the CAA approved SLL values will be incorporated into future amendments of the GV and GV-SP ALS documents.
Decision
Considering the reasons described above, the CAA has decided not to adopt FAA AD 2023- 02-02.
Comments
Enquiries regarding this decision should be referred to:
Continued.Airworthiness@caa.co.uk
