Astra / Westwind Fall 1999

• New SPX STCs Are On The Way
• Watch Out For Flap/Slat Flex Cable Cracks
• Some Tips About AD 99-17-05
• Always Preload Your Torque Wench

New SPX STCs Are On The Way

STCs are being developed by Duncan for SPX aircraft in response to recent JAR requirements which go into effect in the year 2002. They will cover: The installation of a Universal Cockpit Voice Recorder, and installation of an AlliedSignal Digital Flight Data Recorder for the Astra SPX.

Although the STCs are being developed to accommodate European aircraft, they will also be applicable for domestic aircraft.

Also of interest to SPX owners, Duncan has received approval on an STC for installation of an AlliedSignal Enhanced Ground Proximity Warning System with Windshear.

For more info, contact Gary Harpster in LNK at 800.228.4277 or contact Bob Stickler in BTL at 800.525.2376.

Watch Out For Flap / Slat Flex Cable Cracks

During an Astra C check inspection Duncan techniciansfound the flap and slat flex drive cable ferrule ends cracked. The latest revision of the maintenance manual now has limits for cracks and damages. After discussion with Galaxy Tech Services it was determined the old style cable could not be replaced with the new style SPX cable, even though the IPC lists it as a superseded part.

For more info, contact Tim Garity in LNK at 800.228.4277 or contact Jim Overheul in BTL at 800.525.2376.

Some Tips About AD 99-17-05

AD 99-17-05 deals with inspecting the engine main fuel lines where the fuel pressure transmitters are mounted on SPX aircraft S/Ns 089-115. Astra Alert Service Bulletin 1125-73A-191 R1, details the inspection/replacement of the fuel line. Astra Service Bulletin 1125-73-221 details replacing the fuel lines and relocating the fuel pressure switches. The AD has no mention of Service Bulletin 221 or any terminating action. A letter from the FAA to Galaxy Aerospace, dated September 19, 1999, approves Service Bulletin 1125-73-221 as an acceptable alternative method of compliance and terminating action for AD 99-17-05 and eliminates the repetitive 25 hour penetrant inspection.

For more info, contact Tim Garity in LNK at 800.228.4277 or contact Jim Overheul in BTL at 800.525.2376.

Always Preload Your Torque Wench

Preloading a torque wrench is an important process in overall accuracy of these tools. It must be performed each time the torque wrench is used after periods of non-use or whenever torque direction is changed.

There are several reasons for preloading your torque wrench. First, it will set internal components so that when force is applied, torque begins immediately with no internal settling. Second, it distributes lubrication to moving internal parts. The final reason is the hysteresis characteristic of the steel, initial stress should be applied to the steel in order to moderate the hysteresis presence.

How to do it:

1. Set torque wrench between 50% & 100% of full scale.
2. Mount torque drive in a stationary fixture (i.e. socket welded to bench, vise).
3. Exercise the torque wrench 3-5 times in the direction you will be verifying.
4. Perform torque measurement.

Remember to store torque wrenches (Click-type) in the low setting. Otherwise calibration will be needed at shorter intervals.

Contact Duncan’s Calibrations Lab for additional info at 800.228.4277.

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