Here's an update on this issue. It has been confirmed by Dynon support that I cannot restore my firmware backup because you cannot go from a later version (5.4) to an earlier version (4.2). I also cannot do a clean installation of 4.2 in the field. This would "brick" the unit. My only option to get back to 4.2 is to ship it, and remote compass, back to Dynon for disassembly, manual programming of various chips, reassembly and recalibration. I’m in New York. When you factor in the removal of the unit, round trip shipping, two week turn around, reinstallation and recalibration, I’m looking to be down for almost a month. This would also invalidate my 91.411 IFR cert and ensure that I would never want to update the firmware again.
Is there any chance that Dynon would consider a software fix? I can think of a few possible solutions:
1. Provide an option in the setup to define the resolver type. If an external resolver is defined, then the unit would always follow the OBS setting being output by the SL-30. This would be the way it operated up to 5.0.
2. From this thread: “The SL-30 will tell us that it's on an ILS, but only when the ILS is active and not flagged. We use this to ignore the fact the OBS is being sent to us and let the user adjust it themselves. However, we can't do this until the ILS is alive.” The SL-30 uses the selected frequency to determine if a localizer has been selected. The SL-30 passes the selected frequency to the D-10A at all times. Why can’t the soft keys to set the inbound course be available once the Dynon sees that a localizer frequency has been selected, instead of when the localizer is alive? Granted the D-10A would still not follow the external resolver for an ILS, but it would allow all users to set the inbound course early in the approach.
3. Provide a setup option that tells the D-10A to always ignore the SL-30 OBS and always provide the soft keys. While this would be the least desirable option, I would rather be in a position where I always had to set the inbound on the Dynon, as long as I wasn’t forced to wait until late in the approach. Think about it, at about the same time the soft keys become available, ATC is turning you, giving your approach clearance, hand off to tower, etc. This is not the time to be bringing up soft keys and slewing the inbound.
If you were to implement 1 and 2, then I believe you would completely solve this issue for all end users.
I’m not faulting Dynon. What is truly frustrating is all that I’m asking for is the restoration of the functionality that I’ve had since the day I purchased the unit, five years ago. I read the release notes prior to updating and there was no mention of this issue. As stated above, I use the D-10A primarily as an EHSI. The EFIS screen is only a backup to a vacuum attitude indicator.
Please fix this.
Thank you,
Scott