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What are these?? GRT EFIS

Marty G

I'm New Here
I'm getting to know my new GRT Horizon 10.1 and I can't figure out what these two figures are on the PFD. I can't find them in the manual either.

The one to the right of the altimeter tape seems to come and go, but I'm not exactly sure what triggers it to appear or what it is.

I circled them in orange on the attached photos.

Thanks in advance!

Marty
 

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I think this will answer the first question.

Screen Shot 2022-04-04 at 7.12.07 PM.png

Still looking for an answer on the second question.
 
As Dave says, I think it has to do with RAIM (Receiver Autonomous Integrity Monitoring) sequencing when you have something entered in your flight plan page, such as a destination, and possibly an approach. Becomes more accurate/sensitive when you get closer to destination or on final approach to a runway. I believe that 1.2 would indicate you are on an enroute segment of your flight plan, as in your example. In Dave’s example of .3, I think that he is on a final segment of his flight plan, probably final approach. In both cases, 2 dots in the examples indicate 2 dots off course, but the distance off course depends on the phase of flight. RAIM ensures available satellite signals meet the integrity requirements for a given phase of flight. This is an IFR requirement for GPS navigation, and something you should check when conducting GPS IFR flights, including approaches. RAIM coverage can be checked on the ground before you take off. It has to do with satellite coverage. If you get a positive RAIM check, you should be good to go, but you should check your RAIM number before completing a GPS approach if it is one requiring it, such as an LPV approach.
 
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Second photo: orange circle shows the difference between current barometric altitude and gps altitude (ref: pilot’s guide page 45).
 
I believe that 1.2 would indicate you are on an enroute segment of your flight plan, as in your example. In Dave’s example of .3, I think that he is on a final segment of his flight plan, probably final approach. .

Above is correct. When on an instrument approach the CDI will become more sensitive as you get close to the airport. This is to mimic an ILS which, because it is an angular deviation, automatically becomes more sensitive (in terms of a linear, or distance deviation) as you get close to the airport.

RAIM is automatic with WAAS boxes. If satelite coverage is forecast to be insufficient the gps box will warn you.
 
Above is correct. When on an instrument approach the CDI will become more sensitive as you get close to the airport. This is to mimic an ILS which, because it is an angular deviation, automatically becomes more sensitive (in terms of a linear, or distance deviation) as you get close to the airport.

RAIM is automatic with WAAS boxes. If satelite coverage is forecast to be insufficient the gps box will warn you.

There are three horizontal CDI scale sensitivities for GPS (WAAS or standard) - enroute, terminal area (within 30 miles of destination airport) and approach (I believe it is either when acquiring the final approach course or after passing the FAF).

Larry
 
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