P&W Engines Summer 2007

• PW305A & 305B Engine Fan Blades
• PW500 Series On-Wing Low Utilization Engine Inspection (LUI)
• Foreign Object Damage (FOD)

PW305A & 305B Engine Fan Blades

— Ken Kuchenreuther

On May 16, 2007, Pratt & Whitney indicated through SIL PW300-086 (now revision 2) that a PW305A engine had experienced a fan blade fracture across the airfoil just above the platform that resulted in release of the fan blade. Though no other releases have occurred that I am aware of, Pratt & Whitney has aggressively pursued the detection of any further cracking through the release of SB PW300-72-24582. The bulletin was issued to orchestrate a step-by-step procedure for a Fluorescent Penetrant Inspection (FPI) to detect any cracks in the airfoil from the platform extending out the blade for two inches on the suction side. It is recommended that this inspection be done at the next IBR inspection (First Stage High Pressure Compressor Rotor Inspection) or the next time the fan is removed. As with the IBR, Pratt & Whitney is providing financial support for the FPI of the fan blades.

For more information about IBR and FPI inspections or to schedule yours, please contact me by phone at 269.969.8486.

PW500 Series On-Wing Low Utilization Engine Inspection (LUI)

— Ken Kuchenreuther

In the applicable Pratt & Whitney Maintenance Manual (PW500 series engines on the Bravo, Encore, 560Excel, and 560XLS) Chapter 05-20-00, section 4, Low Utilization Engine Inspection Program, Pratt & Whitney discusses the procedure for LUI. The program recommends that the engine be removed and sent to an approved overhaul facility, such as Duncan Aviation, for the LUI if engine has not been subjected to an overhaul type inspection within a period of ten years previous. Pratt & Whitney has recently released SIL PW500-027 indicating the Maintenance Manual will soon be revised to ease those requirements and allowing the inspection to be done “with a comprehensive and periodic field inspection” of the engine.

Foreign Object Damage (FOD)

— Dick Hyde

Aviation experts agree that FOD inside or outside your aircraft can be extremely serious. External FOD may be nothing more than a small rivet or other object on the ramp or runway. Tire punctures are common with runway FOD. FOD also comes from objects flying or floating in the air. “Bird strikes” are common around bird fly-way areas, rivers and lakes. Other examples are blowing sand, dust or volcanic ash and wildlife on or near runways.

Internal FOD may be an object left behind after maintenance. It may be trapped behind a panel or floorboard. It may even be part of the airplane that was not returned to its proper place. Duncan Aviation technicians have found items ranging from tie-raps, avionic control buttons, pencils and even an auxiliary gear handle. FOD trapped under floorboards could be a potential hazard to the safe operation of an aircraft. Sharp objects found lying on wire bundles, hydraulic lines, pitot / static lines, etc. are especially dangerous and can have a chafing potential which can lead to catastrophic failure. Recently, Duncan Aviation technicians have seen a rise in the level of internal FOD.

Carelessness with FOD should not be tolerated and strict procedures must be adhered to. Duncan Aviation is extremely serious about FOD, and has an inspection process in place to ensure that all foreign objects, regardless of area of origination, are secured prior to panel / floor close up. Duncan Aviation advises that operators review FOD procedures at any maintenance facility you might be considering to be sure FOD is taken seriously.

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