Astra / Westwind Winter 2007

• Astra Central Tank Upper Attach Hardware
• New GPS Leading You Astray?
• Intelli-Conference May 15 in Battle Creek, Michigan

Astra Central Tank Upper Attach Hardware

• Tim Garity

Recently, it has been discovered that the hardware for access doors 56 and 56A, on some aircraft, are being corroded by moisture intrusion. If the screws corrode, the screw heads can depart the aircraft and enter the engine inlet. These eight doors provide access to the central tank upper attach points and are located on the side of the fuselage at approximately station 283.0. Until a Service Bulletin is released, Gulfstream has provided repair guidelines as follows:

Repair instructions:

• After removing (4 + 4) covers, 25W316111-021:
  • Drill out existing Nut-Plates, MS21075-08.
  • Abrade inner side of structure from remains of paint/corrosion and faying surface on the outer side to remove dirt and remains of paint, use abrasive paper #280 grit, without damaging parent material.
  • Clean with acetone and wipe dry by forced air.
  • Clean inner side of Bracket, 25W316112- 003, from debris, metal burrs and sealant that have been stuck on its lower corners next to forward and aft frames, sta. Y=276.55 & Y=287.75. (Don't drill any new drainage holes, not damaging fuel tank!)
  • Slightly clean corrosion from nuts and studs (supporting inner pipes) using a fine rotated metal brush. Apply corrosion protective compound per Mil-C-16173 Grade 1, or equivalent.
  • Touch up aluminum exposed areas with conversion coating per Mil-C-5541 and epoxy primer per Mil-P-23377.
• Install from inner side new nut-plates, MS21076L08 (cres), 3 places, with rivets blind CCR264CS-3-(*) (cres), wet with epoxy primer.
• Apply "from in place gasket" on skin doubler with PR1750 per P.S. 313100. Re-install covers with new bolts NAS1992C1T (cres).

Note: For nuts and studs (see para. "A" ), they should stay as is until a new fuel bag would be installed.

New GPS Leading You Astray?

• Trent Fuller

Within our avionics repair team, our HSI specialists have fielded several calls from customers whom, after installing a repaired (or new) panel-mounted GPS, received consistently inaccurate HSI course readings. These GPS units functioned properly on our bench. And the HSIs functioned properly prior to the GPS (re)installation, but troubleshooting pointed to the HSI and unit-swapping reduced the errors. So what caused the errors? One critical step: the “initial alignment” or “test set-up.” For help with this process, contact us at 800.LOANERS.

Intelli-Conference May 15 in Battle Creek, Michigan

• Beth Humble

Our Intelli-Conferences will continue this year as we unveil our expansion in Battle Creek. These symposiums are a natural extension of the Duncan Intelligence publications and are your chance to discuss aviation issues with knowledgeable industry professionals in a face-to-face forum. The May 15, 2007, event will feature six unique sessions, four of which are approved for IA renewal credit. We will be giving tours of the remodeled and expanded facility and will wrap up the event with our signature dinner experience. Look for more information on our website and in the mail soon!

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