Position relative to the glideslope. The range is -1 to +1, where -1 and +1 are full scale deflections of the needle to either side. Positive values indicate too high, and negative values indicate too low. Returns 0 if no glideslope is available. Signed fractions. Read-only.
Example
IF VOR_1_GS_DEVIATION < -0.1 THEN
PRINT "You are getting low on the glideslope."
ENDIF