Airworthiness Directive 2006-17-08
one-timeAirworthiness Directives; Pratt & Whitney PW4077D, PW4084D, PW4090, and PW4090-3 Turbofan Engines
What this AD requires
The FAA is adopting a new airworthiness directive (AD) for Pratt & Whitney (PW) PW4077D, PW4084D, PW4090, and PW4090-3 turbofan engines that were reassembled with certain previously used high pressure compressor (HPC) exit brush seal assembly parts and certain new or refurbished HPC exit diffuser air seal inner lands. This AD requires replacing the HPC exit inner and outer brush seal packs with new brush seal packs, or replacing the HPC exit brush seal assembly with a new HPC exit brush seal assembly. This AD results from a report of oil leaking into the high pressure turbine (HPT) interstage cavity and igniting, leading to an engine case penetration and engine in- flight shutdown. Although liberated engine parts did not penetrate the engine nacelle, we are issuing this AD to prevent uncontained engine failure, damage to the airplane, and injury to passengers.
Which aircraft AD 2006-17-08 applies to
Applies only to engines reassembled with a previously used HPC exit inner brush seal pack (P/N 50J894-01) and a new or refurbished HPC exit diffuser air seal inner land (P/N 55H869).
Whether AD 2006-17-08 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.
How AD compliance is recorded
A valid compliance record (14 CFR 43.9) states:
Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.
Look up a tail number →Read the full directive (Federal Register)Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.