Hawker Fall 1999

• Always Preload Your Torque Wench
• Need Information About Your Cockpit Water Coalescer?
• Don't Let Your DEEC Annunciator Light Annoy You
• Watch Out For That Dreaded Corrosion

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.

Need Information About Your Cockpit Water Coalescer?

If your aircraft was outfitted by Ark Mod, you may have a cockpit water coalescer in the tailcone. You will not find information about this in the maintenance manual or Chapter 5, only in the addenda. This sock (P/N 800-8234-64) is required to be changed at 1,200 hours. Many operators are not aware they have this installed.

For more info, contact Roy Olsen in BTL at 800.525.2376 or contact Dick Hyde in LNK at 800.228.4277.

Don't Let Your DEEC Annunciator Light Annoy You

If the flight crew of your Hawker 800 reports a flashing DEEC annunciator light shortly after engine shutdown, and the light is extinguished after battery power is cycled off and on, a fault in the ITT circuit is suspect. To correct the problem, perform a DEEC bite check.

For more info, contact Doug Alleman in LNK at 800.228.4277 or Ken Kuchenreuther in BTL at 800.525.2376.

Watch Out For That Dreaded Corrosion

Hawker 800 structural inspection task code #530003, 12-year then 8- year requirement, which addresses the wing to fuselage attachment links, brackets and bolts, usually requires bolt and/or link replacement due to corrosion. If a bearing housing is found to be corroded, it can sometimes be properly dressed without replacement; however, if bearing replacement is required, Raytheon will supply an oversized bearing kit for the procedure.

Rear mounts can be drilled to the next size if found worn. Also, the forward mounts on the wing (aircraft jacking point) may need to be removed and sent to England for repair if worn beyond limits. Availability of the forward mounts for replacement may be difficult to obtain. Some operators have identified a “clunking” sound under the passenger deck.

The above inspections may add several days to your aircraft’s schedule if worn parts and/or corrosion is found.

For more info about corrosion, and what it can do to your aircraft & your schedule, please contact Jeff Manion in LNK at 800.228.4277 or contact Pete Kilmartin in BTL at 800.525.2376.

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