Learjet Spring 1999

• 8.33 Corn Radio Modifications Are Here!
• Nose Gear Door Attachment Bolt Problems?
• Constant Bleed Air Bewilderment?
• Take Care Of Your Aeronca Thrust Reverser’s
• Thinking About An N Number Change?

8.33 Corn Radio Modifications Are Here!

On October 7, 1999, all flights above FL245 in Austria, Belgium, Germany, Luxembourg, Switzerland, the United Kingdom and France (above FL195) will require radios operated between 118-136.975MHz to be capable of channeling frequencies with 8.33kHz spacing to ease overcrowding of the Corn frequencies in congested areas. The aircraft must be equipped with two 8.33 Corn radios to meet this requirement.

Rockwell Collins has recently released a service bulletin to upgrade the VHF-21/22/422 Corn Radios to include the European-mandated 8.33 frequencies. Modifications to the Collins CTL and RTU Controllers are also available.

For more information, please contact Dave Pleskac, Ron Hall or Gary Harpster in Lincoln at 1.800.2284277, or Bob Stickler or Dennis DeCook in Battle Creek at 1.800.525.2376.

Nose Gear Door Attachment Bolt Problems?

Learjet operators should be aware that Duncan Aviation continues to find occurrences where the Nose Gear Door actuating rod attachment bolt is improperly installed. This bolt is easy to install at the strut attach point with the head facing inboard and looks appropriate once it is installed. However, the bolt must be installed with the head facing outboard in order to maintain proper clearance and avoid gouging of the wheel well skin at frame 5 as the gear is extended and retracted.

Failure to install this bolt properly is resulting in costly and unecessary repair bills for many operators. Double check the installation and the possibility of previous damage to your aircraft at your earliest convenience.

For more information, please contact Skip Laney in LNK at 800.228.4277 or Pete Kilmartin in BTL at 800.525.2376.

Constant Bleed Air Bewilderment?

If your records indicate that you are overhauling your bleed air regulating and mixing valves approximately every 12 months, you are probably experiencing ITT Splits, pressurization bumps, and/or asymmetric thrust reverser deployment. A potential solution is Duncan’s bleed air mixing valve mod that can virtually eliminate these operational situations while also extending the service life of the mixing valves. Lear Model 35 and 55 operators who have incorporated this modification are having three to four years of trouble-free service and operation.

For more information, please contact Skip Laney or Chris Gress in LNK at 800.228.4277 or Pete Kilmartin in BTL at 800.525.2376.

Take Care Of Your Aeronca Thrust Reverser’s

In response to customer demand, Duncan Aviation’s Accessory shop now offers “send in” 1,400 hour inspection on L e ar 35/36/55 Aeronca Thrust Reverser’s.

For more information, please contact Skip Laney or Chris Gress in LNK at 800.228.4277 or Pete Kilmartin in BTL at 800.525.2376.

Thinking About An N Number Change?

If you plan on changing the registration number of your aircraft and you currently have an LOA (Letter of Authorization) to operate your aircraft in the North Atlantic Minimum Navigation Performance Specification airspace, then prior to changing the registration number, you must notify the Flight Standard District Office that issued your LOA of your intentions. They will contact the manager of the FAA RVSM database who will update the FAA RVSM records and notify the International Civil Aviation Organization about the change in your number.

For more information, please contact Dave Pleskac, Ron Hall or Gary Harpster in Lincoln at 1.800.228.4277, or Bob Stickler or Dennis DeCook in Battle Creek at 1.800.525.2376.

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