Problem With ILS DA Callout

[Jetstar2 1]

Hello, I recently did a flight into KGSO using the Cat I ILS app into runway 5. According to my jepp chart, the DA is 1101. I set the red bug on the altimeter to 100 feet, since the manual states anything in the 1000's is automatically added. However I received no callout for minimums (or 100 feet within minimums) when I flew the app and again for the go around app (the AI planes give me headaches :) I'm curious as to what happened. Does it make a big difference if there was a small discrepancy between my Jepp chart and the databases touchdown threshold altitude (TDZE)? Also, does the radar altimeter callout setting matter? I'm assuming it doesn't affect the FO's callouts in any way. I had it set to 400 feet because I didn't want it to interfere with the FO's callouts and according to an earlier post, the FO complains if the radar altimeter isn't set at all. Robert Williamson

[byork 2,260]

Hello Robert,Typically on a CAT1 approach you can set the RA to 200 feet. It's a bit pointless though because the terrain in front of the runway may not be perfectly flat or even with the runway, but some people like to do it that way. DA at KGSO: There is an anomaly with the DA when the runway elevation is in the 800 to 999 feet range. FS2Crew's internal math gets confused when the rwy elev is in this range. What happens is that when the runway is in that range, FS2Crew does "not" add 1000 feet to the bugged setting. So if the bug is set to 101 feet and the runway elev is 900 feet for example, FS2Crew computes the DA as being 101 feet.It's a known issue that will likely be corrected when the FSX update is available.(You could always set the approach mode to an NP and then add 1000 feet to the additive... it's not a perfect work around obviously, but you should still get your Decide call at the mins).Bryan

[Jetstar2 1]

Roger, thanks for the info! Robert Williamson