Pratt & Whitney recommends that the JT8D main oil filter/strainer (MOF) be removed for "routine inspection" at an interval between 250 and 400 hours. The primary reason for MOF inspection is to monitor the condition of the engine's oil system (including oil-wetted parts and compartment sealing). This article provides some insight into developing the best MOF inspection interval for any specific set of operating conditions. See the SIR for this important information.

Fan hub face skim cut repair 72-31-01 Repair-11 has been revised to enhance the details in JT9D-7R4 engine manuals. Recent repair anomalies have prompted Pratt & Whitney to review the procedure. To better serve 7R4 operators, Repair-11 has been revised to better clarify the skim machine area by adding additional views to Figure 901. See the SIR for the details.

The latest version (February 28, 2008) of the PW2000 Maintenance Planning Guide (MPG) is now available online. MPG's consolidate maintenance data in a single document and identify "best practices". The updated MPG incorporates fleet experiences into maintenance recommendations and has accessory component soft times and workscopes that have been reviewed and updated if required. A new section titled Highlights has been added that shows which sections of the MPG have been revised.

Two Borescope Inspection Reference Cards are now available in the Repetitive Maintenance section for the PW4000-94/-100 engine models. The first is PWA 107298 for PW4000-94/-100 HPT 1st and 2nd Stage Blade Internal Sulfidation. The second is PWA 107586 for PW4000-94/-100 HPT 1st Stage Vane Material Burn Through and Expanded Limits for Leading Edge Burn Through (All Vanes). See the cards online for more details.

The redesigned PW4090 2nd stage turbine blade task has been completed and SB PW4G-112-72-292 has been released with the new configuration blade, damper, seal and metering plates. The new blade incorporates design improvements that address various distress modes that the blade had been experiencing, the two most significant modes being under platform Stress Corrosion Cracking (SCC) and Thermal Mechanical Fatigue (TMF) cracking. See the SIR for the details.