Gulfstream Winter 2004

• Swapped Anti-Skid Hydraulic Lines In Main Landing Gear Wheel Wells
• Vertical Stabilizer Attach Fitting-Alternative Inspection
• ELT Situation Supports Solid RVSM Date

Swapped Anti-Skid Hydraulic Lines In Main Landing Gear Wheel Wells

— Jim Overheul

There have been several articles written on this issue over the years in the form of customer bulletins and breakfast minutes dating back to 1970. We have seen several aircraft with the brake lines swapped. Most were found during the Antiskid Control System- Functional Check for the GII and GIII. Several were found during our pre/post inspection process, including two aircraft where the lines were installed incorrectly and still passed the 'tweak test'. When the lines were routed correctly the aircraft failed the tweak test. Further investigation revealed the wires at the antiskid control box were swapped. (When the wires were installed per the Gulfstream Wiring Manual the aircraft passed the tweak test.)

For the GIV, you will have to rely on the visual inspection. The Antiskid Control System- Functional Test in the Gulfstream Maintenance Manual will not indicate a swapped line condition. Typical reasons for the lines being removed for maintenance are wing breather angle repair/change, boring of the main landing gear sponson rib aft lug, and upper sponson plate change. For more information, contact Jim at 800.525.2376.

Vertical Stabilizer Attach Fitting-Alternative Inspection

— Jim Overheul

While doing this inspection it is a good idea to dimensionally inspect the bushing housing holes for being oversized beyond standard tolerances. This is especially important for aircraft that may have had attach fitting holes oversized prior to the release of SE05455904 STD REPAIRVERTICAL FIN ATTACH FITTINGS.

A recent inspection revealed an aircraft with this situation. One of the attach fitting holes was oversized, but not to the increments called out in the repair drawing, which left it very close to the std. size. The customer elected to oversize the fitting per the SE05455904 drawing. Since the bushing housing hole can be so close to the standard hole size it may be possible for a standard bushing to be installed during this inspection, allowing it to be out of the bushing to fitting tolerance. Also there may be some additional downtime required to procure this specialized bushing or vertical stabilizer removal to repair.

Finally, it is a good idea to identify any oversized bushing, bolt, etc. for easy visual identification. We are still seeing some aircraft with the CRES bushings and hardware being installed where the low-alloy steel bushing and hardware should be installed.

ELT Situation Supports Solid RVSM Date

— Dave Pleskac

Just as the 01/01/2004 ELT mandate stood firm, we believe the FAA will not budge on the 01/20/2005 RVSM and 05/29/2005 TAWS mandates. Equipment shortages and mods shop schedules left many last minute ELT shoppers unprepared for the mandate, but many of them kept flying by installing a 121.5 MHz ELT until a 406 MHz installation date and equipment is available.

We believe RVSM and TAWS will make the ELT crunch look like small potatoes and there will be no short-term fixes. While many pilots assume they will simply "file for FL270 if the date sticks," there will be great demand for the highest non-RVSM altitudes from non-compliant jets and high-flying turboprops. This will result in even lower available altitudes which translate into more fuel consumption and refueling stops for passengers accustomed to nonstop flights.

Now is the time to gather the facts and take action toward meeting these mandates. If you have TAWS or RVSM questions, call us for a free copy of Straight Talk about TAWS or our recently released Straight Talk about RVSM: 2nd Edition or visit DRVSM.com.

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