# Units for var "A:NAV1 GLIDE SLOPE" ??

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Hi,I'm trying to read the glideslope value for an ILS in NAV1.For a glideslope of 3 degrees it gives the number 6859For a glideslope of 3.5 degrees it give the number 8001Now, these numbers (6859/8001) must have a relation with the glideslope angle (it's the same ratio), but I haven't been able to figure out in what units this is.Anyone ?Rob

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>Hi,>>I'm trying to read the glideslope value for an ILS in NAV1.>>For a glideslope of 3 degrees it gives the number 6859>For a glideslope of 3.5 degrees it give the number 8001 They are in the correct ratio.>Now, these numbers (6859/8001) must have a relation with the>glideslope angle (it's the same ratio), but I haven't been>able to figure out in what units this is.>Rob It looks like value/(2*64K) is angle in radians. Multiply by 57.3 to get degrees. Ron

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Try "A:NAV GDI:1", you mean fs2004, right?It will return value in [-127, 127] range

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No, I did mean "A:NAV1 GLIDE SLOPE".And yes, I knew the values fir NAV GDI :-)But somehow the Subject line seems to be cutoff in the reply.And Ron was right (Thanks Ron !):8001 * (180 / 3.14) / 131072 = 2.99 degrees glideslope which is correct for that ILS.I just wonder where that funny measure (Radians*128K) comes from :-)Rob

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InterestingSo try "A:NAV1 GLIDE SLOPE,degrees" for avoiding conversion :)

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Tried every unit I could think of:degree, degrees, degrees angl16, degrees angl32, etc etc.All kinds of values, but not the right one :-)So dividing the unit "number" by (131072 / 180 * 3.1416) = 2287.6gives me the right value.Rob

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>..>And Ron was right (Thanks Ron !):>>8001 * (180 / 3.14) / 131072 = 2.99 degrees glideslope which>is correct for that ILS.>>I just wonder where that funny measure (Radians*128K) comes>from :-)>Rob There are a lot of units given in the SDK. 'gauges.h', I think. I also thought the scale factor was strange but didn't check gauges.h to see if it was shown anywhere. For all I know, there is an error in the FS DLL that requires that scale factor. I often have to experiment in XML test gauges to figure out a scale factor if the expected 'type' scale does't work. It turns out reciprocating engines yield Power in Watts (or kW), there doesn't appear to be any 'HP' factor. So, I had to convert 'Watts' to 'HP' myself. Ron

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