Learjet Summer 1998

• Cockpit Temperature Control Operating Intermittently?
• Radar Window
• Aircraft Sales & Acquisitions
• Our Engine/Airframe Road Teams Know YOUR Aircraft
• TFE731-2 High Pressure Turbine Blade Separation Program

Cockpit Temperature Control Operating Intermittently?

Duncan’s Accessory Shop has recently received FAA approval to repair the housing bores on the commonly worn out Cockpit Temperature Modulating Control Valve P/N 979686-4 or P/N 6600423-11 found on the Lear 55. This repair restores smooth valve operation and saves the aircraft operator money on repair charges.

For more information, please contact Chris Gress in Lincoln at 800.228.4277 or Bob Stickler in Battle Creek at 800.525.2376.

Radar Window

The radome is your radar’s window to weather and needs to be kept clean to optimize radar performance. Some quick and easy things to keep in mind when considering radar performance are: Ensure that the static bonding strips are correctly “bonded” to the airframe and in good physical condition. The radome boot should be in good shape and correctly installed. The physical condition of the radome should be checked for soft spots or delamination. If any of these areas needs attention, a good avionics shop should be able to help you correct the problems.

For more info, contact Rick Whitesell in Lincoln at 800.228.4277 or Bob Stickler in Battle Creek at 800.525.2376.

Aircraft Sales & Acquisitions

Selling your Lear can be a stressful time, and what can be even more stressful is buying a pre-owned aircraft. Stress from both these situations can be greatly reduced at the pre-buy evaluation.

When selecting a facility for a pre-buy evaluation, look first for a company that can be recommended by other operators. The facility should be full service, complete with engine and avionics diagnostic capabilities. Other overlooked qualifications include import and export services and on-staff DAR services.

All of the above, with the right pre-buy evaluation checklist, developed through years of experience, will help you select a high-quality, pre-owned aircraft and a quality service facility.

For more info, contact Bob McCammon at 800.228.4277.

Our Engine/Airframe Road Teams Know YOUR Aircraft

Because of customer demand, Duncan technicians at both our facilities make dozens of “in the field’ road trips every year in order to help customers who cannot get their engines to a service facility.

For more information, please contact Skip Laney, Cecil Sloan or Jon Dodson in Lincoln at 800.228.4277 or Dan Arrick in Battle Creek at 800.525.2376.

TFE731-2 High Pressure Turbine Blade Separation Program

In July of 1991, AIliedSignal issued the “vaneless space” SB TFE 731-72-3434, which addressed high cycle fatigue blade separation on HPT blades P/N 3072712 for TFE731-2 engines. No high cycle life fatigue separations of HPT blades installed new since this SB was incorporated have been reported.

In February of 1994, SB TFE731- 72-3494 was issued which recommended turbine blade life tracking. Revision 1 identified turbine blade service lives and established a stress rupture life for the HPT blade at approximately 4,500 hours. Since that SB, a number of stress rupture blade separations have been reported with blade lives less than the limit.

To reduce the incidents of HPT blade separations, temperature exposure of the blade must be reduced. SB TFE731-72-3494 has been revised to a 3,000 hour HPT blade life. Because of the life reduction impact on cost ownership, the “TFE73 l-2 High Pressure Turbine Blade Separation Program” has been continued and amended.

For more info about the TFE731-2 High Pressure Turbine Blade Separation Program, call Cecil Sloan or Jon Dodson in Lincoln at 800.228.4277 or Dan Arrick in Battle Creek at 800.525.2376.

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