AD NUMBER: 2006-17-07
MANUFACTURER: Pratt & Whitney
SUBJECT: Airworthiness Directive 2006-17-07
SUMMARY: The FAA is superseding an existing airworthiness directive (AD) for Pratt & Whitney (PW) JT8D-209, -217, -217A, -217C, and -219 turbofan engines. That AD currently requires initial and repetitive visual inspections for fretting and fluorescent magnetic particle inspections (FMPI) for cracking in the area of the tie rod holes on 8th stage high pressure compressor (HPC) front hubs (from here on, referred to as HPC front hubs) that have operated at any time with PWA 110-21 coating. This AD requires either replacing HPC front hubs and HPC disks that have operated at any time with PWA 110-21 coating and that operated in certain engine models, or, visually inspecting and FMPI for cracking of those parts and re-plating them if they pass inspection. This AD also requires adding JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R,and -17AR engines to the applicability. This AD results from an investigation by PW, which concluded that any HPC front hub or HPC disk coated with PWA 110- 21 that ever operated on JT8D-15, -15A, -17, -17A, -17R, -17AR, -209, -217, -217A, -217C, and -219 turbofan engines, could crack before reaching their published life limit. We are issuing this AD to prevent a rupture of an HPC front hub or an HPC disk that could result in an uncontained engine failure and damage to the airplane.

FMI: www.faa.gov/regulations_policies/airworthiness_directives/