Dynon IFR
When doing my initial system configuration designs for both Garmin and Dynon wish list I looked at the installation documentation quality and detail. Garmin was detailed and professional and what would be expected for a TSO?d system. Dynon mostly adequate but lacking in detail about interface definitions -particularly the GP and EGP interfaces for the EMS-220. Calling Dynon and asking for the interface characteristics in two port format or equivalent circuit format got nowhere with the tech support guys and they wouldn?t refer me to their engineering department. The Garmin documentation has the necessary information in the TSO?d version of the documentation. Additionally, and more importantly the Dynon system architecture has a number of single point failures for a two display system. They may be unlikely failures but they are built into the system architecture and impossible to work around unless you build two completely separate display systems isolated from each other. Two examples - GPS- 2020 - HDX requires both displays to be tied to the same GPS - putting a second GPS - 2020 or the older GPS-250 on the second display is not permitted and will result in system malfunction according to Dynon Tech support. The other significant single point failure is in the ADAHRS primary and secondary being tied through the same bus connection. A shorted bus line or babbling bus from one ADAHRS will result in loss of ADAHRS data to both displays. These failures may be unlikely but they would result in loss of important data during IFR flight for a single failure. I haven't looked at the Garmin system in enough detail to convince myself that there are no single point failures that would be as significant in IMC flight. I would be suprised if there were - but I dont know for sure. So- if you are putting together a configuration for serious IFR Dynon is probably not the answer.
KT
When doing my initial system configuration designs for both Garmin and Dynon wish list I looked at the installation documentation quality and detail. Garmin was detailed and professional and what would be expected for a TSO?d system. Dynon mostly adequate but lacking in detail about interface definitions -particularly the GP and EGP interfaces for the EMS-220. Calling Dynon and asking for the interface characteristics in two port format or equivalent circuit format got nowhere with the tech support guys and they wouldn?t refer me to their engineering department. The Garmin documentation has the necessary information in the TSO?d version of the documentation. Additionally, and more importantly the Dynon system architecture has a number of single point failures for a two display system. They may be unlikely failures but they are built into the system architecture and impossible to work around unless you build two completely separate display systems isolated from each other. Two examples - GPS- 2020 - HDX requires both displays to be tied to the same GPS - putting a second GPS - 2020 or the older GPS-250 on the second display is not permitted and will result in system malfunction according to Dynon Tech support. The other significant single point failure is in the ADAHRS primary and secondary being tied through the same bus connection. A shorted bus line or babbling bus from one ADAHRS will result in loss of ADAHRS data to both displays. These failures may be unlikely but they would result in loss of important data during IFR flight for a single failure. I haven't looked at the Garmin system in enough detail to convince myself that there are no single point failures that would be as significant in IMC flight. I would be suprised if there were - but I dont know for sure. So- if you are putting together a configuration for serious IFR Dynon is probably not the answer.
KT