Garmin GTN v3 firmware - sensor data disabled

I have just come across the following on a US site, which if I read it correctly sounds like the GPS would no longer be able to calculate the Landing Fuel on Board, because the interface to the fuel totaliser was disabled. They reinstated that functionality in v4.10. This may have some impact on EASA-reg users who have/have had to wait a long time for this firmware update.

Hello everyone,

I need to correct a post that I had made on this subject after some research on the 3.0 S/W GTN release. My apologies on this as I misunderstood the software engineering document on this function as I had to do some additional testing on it and communication with our team on it.

As you all may or may not know with the new 3.0 GTN software we had to remove the "Use Sensor Data" button off of the winds and fuel planning pages at the request of the FAA as this was possibly adding confusion to the operation of these pages. I had originally understood that with this button removed the GTN would default to the fuel data source if the system was configured for such, regrettably this was incorrect.

If you have a fuel data source that is approved for the GTN on the STC it will show you field data on the initial boot up screen for the GTN on the self test page, it will not show on the fuel planning page any longer as this is now purely a manual entry page. Below is a list of the winds and fuel page and what each field will default to and it's function:

For the DALT/TAS/Winds page, this includes the following data: (____ means dashed lines or blank)

1. Indicated altitude (defaults to ____, must be manually entered by the user)
   
2. Baro (defaults to 29.92, must be manually entered by the user if actual conditions are other than 29.92)
   
3. CAS (defaults to ____, must be manually entered by the user)
   
4. TAT (defaults to 15, must be manually entered by the user if actual conditions are other than 15)
   
5. TRK (defaults to ____, must be manually entered by the user)
   
6. HDG (defaults to ____, must be manually entered by the user)
   
7. GS (defaults to ____, must be manually entered by the user)
   

Once this data is entered, it is ‘saved’ for the power cycle. The unit will revert to the defaults after a power cycle.

For the fuel planning page:

1. Fuel on board (see below for the default, must be manually entered by the user if other than the default)
   a. Once the Fuel Planning page is viewed, fuel on board only decrements by the fuel flow when viewing the page. It does not continue to decrement once the page is viewed and the user goes to a different page. This is being fixed in 4.00.
   
2. Fuel Flow (see below for the default, must be manually entered by the user if other than the default)
   
3. GS (defaults to 120, must be manually entered by the user)

For the trip planning page:

1. GS (defaults to 120, must be manually entered by the user)
   

Again my apologies if there was any misunderstanding on this feature.

Feel free to contact me with any questions,

Trek A. Lawler Supervisor, Garmin Aviation Field Service Engineering Aviation Product Support