JT8D SIR Article – Page 4: Turbine Rear (LPT) Case Wall Thickness – JT8D-200

A JT8D operator reported occasionally finding LPT cases with wall thickness below the Engine Manual (EM) limit at the rear of the case in the vicinity of the rear flange. Upon investigation P&W found an omission in the EM that is critical to measuring the flange area taper. This SIR article details how the LPT case wall thickness is to be measured and provides an illustration of the changes that may be used in advance of the publication of the EM revision.

JT9D SIR Article – Page 4: JT9D Fuel Pumps – “Large” vs. “Small”

Periodically the question is asked concerning what is meant by the terms “large fuel pump” vs. ‘small fuel pump” when describing the JT9D Fuel Pump configuration. Three of these four descriptive terms cannot be used when describing the “large pump” configuration. This SIR article describes the fuel pump configurations used on the various JT9D engine models.

PW2000 SIR Article – Page 4: Fan Hub Inspection
(SB 72-695) Quarterly Survey To End

The last fan hub inspection quarterly survey was reported to the Federal Aviation Administration (FAA) in February 2009. Customer Technical Service (CTS) has been collecting important data on the completion of PW2000 Service Bulletin (SB) 72-695 since 2006. This data was compiled and then reported at the request of the FAA. This SIR article provides background information regarding the Fan Hub Inspection survey, current compliance results, and the remaining requirements associated with this Service Bulletin.

PW4000 SIR Article – Page 4: The Significance of a Properly Painted Engine Cowl Latch — PW4000-100 Engine Series

Repeated opening and closing of the engine cowls wears the paint that is used to help mechanics and inspectors identify if a cowl is not properly latched. This SIR article provides pictures to review some basic engine cowling latch safety precautions for wing mounted engines.