Date: November 11, 2004

Applies: to all Electronic Flight Information Systems, Model EFIS-D10A with operating program versions 02.03 and earlier. You can check your EFIS-D10A software version by bringing up the menu and selecting: MORE, SETUP, MORE, VRSION.

Please note that this service bulletin does not apply to Dynon's Model EFIS-D10.

Action Required: Download new operating software V 02.04 (or later) into the EFIS-D10A before next flight.

Instructions: The software, Dynon Support PC Program and loading instructions are all freely available at http://www.dynonavionics.com/docs/support_software.html . For best results, use the current Dynon Support PC program V 2.0.13.

Problem: Dynon has uncovered a potentially unsafe condition that is likely to exist or develop with software versions prior to V 02.04, where stored user parameters and certain internal data stored by algorithms are not maintained after 250 changes have occurred. Once this condition occurs, it is permanent, can potentially affect the overall performance of the instrument and can only be remedied by downloading V 02.04 or later.

The condition is easily detected by observing instrument operation while adjusting or changing a user-selectable parameter. For example, changing the BARO will show both the barometer and altimeter changing. However, when the BACK button is pressed, the EFIS will return to the previous value and not store the newly entered value.

The V 02.04 software additionally:

• Fixed: Problem resulting in erroneous serial altitude encoder output over 20,000 feet
• Added: Reporting "Attitude Indeterminate" to warn when started in flight
• Improved: Performance of algorithm when started in flight
• Improved: Attitude performance, including minimizing susceptibility to vibration
• Improved: G-Meter max and min are saved every time they change

Confirmation: Dynon requests confirmation of your receipt of this notice by sending a letter, fax or email to: Gillian D'Ancicco at This e-mail address is being protected from spambots. You need JavaScript enabled to view it or by calling (425) 402-0433. We consider this sufficiently important that we will continue to make contact until we know you have received this notice and taken appropriate action.