Citation Winter 2002

• Warning: Garmin GNS- 430/530 Incompatibility With Older Jet Aircraft Flight Management Systems
• Electric Heated Leading Edges
• Speed Brake Light Flicker
• Citation Troubleshooting Class
• RVSM Service Bulletins

Warning: Garmin GNS- 430/530 Incompatibility With Older Jet Aircraft Flight Management Systems

— Curt Campbell

Duncan Aviation technicians have discovered that an incompatibility issue exists between Garmin GNS-430/530 units and most Collins and Honeywell Flight Control Systems (FMS). In most cases, when GNS-430/530 units are coupled to a Collins or Honeywell FMS, the system will remain in NAV ARM and will not capture. This problem appears to be caused by the method in which the Garmin units provide navigation information to the FMS.

Operators should be reminded that these Garmin units were designed for the light twin and turboprop market. Recently, Duncan Aviation has fielded numerous calls from operators who have installed the GNS- 430/530 in older jet-powered aircraft and who are now experiencing these incompatibility problems.

Duncan Aviation recommends that only systems which are compatible with your current FMS should be installed in older jetpowered aircraft. Duncan Aviation is currently unaware of a solution for this incompatibility issue, although Garmin has been informed of its existence.

Electric Heated Leading Edges

— Joe Austin

On the 500 and 550s, Cessna installed an electric heating edge to keep ice off of the wing in front of the engine during anti-ice system operation.

During operation, you may get a light flicker. Such a flicker indicates that a capacitor within the anti-ice J-box is worn out. Replacing the capacitor will correct the problem. The capacitor is designed to help hold the warning light relay closed and avoid a flickering annunciator light.

If you have any other abnormal annunciator light indications when operating the system, you should have it repaired immediately.

For more information, contact Joe Austin at 800.525.2376 or Ed Johnson at 800.228.4277.

Speed Brake Light Flicker

— Joe Austin

On models 500, 550, S550, 560 and 560XL the actuator does not have an internal locking device to hold the speed brakes closed. Cessna uses studs and clips to hold them closed, but they wear out. When they start to wear, you will get a quick flicker of the HYDRAULIC PRESSURE ON light on the annunciator panel. Usually it is very quick, and unless you look directly at the panel, you will miss the flicker. The system is operating as designed but the intermittent flickering light can be annoying. There are several solutions available to correct the problem. These items can be corrected at your next scheduled maintenance visit.

For more information, contact Joe Austin at 800.525.2376 or Ed Johnson at 800.228.4277.

Citation Troubleshooting Class

— Joe Austin

In the tradition of our Intelligence Faxes, Duncan Aviation will be hosting a 2-day symposium in Battle Creek in May of 2002. The event will offer a four hour course on Citation troubleshooting, as well as many other customer-requested topics, including a session on the JT15D engine. Many of the classes will be offered for IA renewal credit. Log on to www.duncanaviation.com/conference for more information.

RVSM Service Bulletins

— Dennis DeCook

Did you know that Duncan Aviation can complete Cessna factory RVSM service bulletins on your Citation? Duncan Aviation can also guide you through the entire RVSM process in an easy to understand format.

Call Dennis DeCook for more information at 616.969.8418.

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