What does the Alt Desc setting in the approach editor mean? I figure PLUS and MINUS mean at or below the altitude setting under Alt1 and Alt2 Feet, which is what the ADE manual says, but what the heck does A, B, C, G, H, I, J, V and Space mean??? How would you know what to set there? It seems no one on the FSDeveloper website has made reference to this setting, but it does something I assume.I'm just trying to understand the appraoch code better so I can maybe tweak a few incorrect approaches in FS9.Thanks,Chris

What does the Alt Desc setting in the approach editor mean? I figure PLUS and MINUS mean at or below the altitude setting under Alt1 and Alt2 Feet, which is what the ADE manual says, but what the heck does A, B, C, G, H, I, J, V and Space mean??? How would you know what to set there? It seems no one on the FSDeveloper website has made reference to this setting, but it does something I assume.I'm just trying to understand the appraoch code better so I can maybe tweak a few incorrect approaches in FS9.Thanks,Chris

Have you read the relevent Microsoft SDKs? Mine, for FS9, describes these variables.

Oh, no I don't even have the SDK on this HDD. I'll look for it and do a search in the docs. I thought perhaps this was an ADE specific parameter. Thanks.

Oh, no I don't even have the SDK on this HDD. I'll look for it and do a search in the docs. I thought perhaps this was an ADE specific parameter. Thanks.

As far as I am aware, ADE provides a "front-end" to standard Microsoft values for apperoaches which are in XML .

I don't think those variables actually do anything in the sim. The GPS will use the Alt1 value to compute the VSR reading, but that's about it.scott s..

I don't think those variables actually do anything in the sim. The GPS will use the Alt1 value to compute the VSR reading, but that's about it.scott s..

You make a good point. I think Microsoft made provision for most of the ARINC approach variables but didn't implement all of them. I'm not enough of an expert to know which.

Well, I'm playing with the settings to see. In some cases they're too low or completely incorrect. I was given an instruction to descend to 3000 at KMCI when I should've been "At or Above" 4000 according to the charts. MSFS was using Alt2 as the altitude in gave me even though the 4000 was in the approach profile at Alt1.What I wish I knew is why, when selecting an approach and transition, ATC waits so long to clear you to the required altitude. It tells me to fly direct to the transition but then waits way too long to let me get down in time. I'm only 10 miles from a transition point at 12000 feet when I need to be at 5000 and I'm stuck extending my approach on HSG mode or using a hold to get down in time.

Normally, for AI and the default ATC IFR approach for user aircraft, ATC will look at the ILS approach header (if the approach exists) and get the fixIdent, altitude, and heading from it to get the data for the AI or user. The aircraft will be vectored to intercept the "heading" course outside of the "fixIdent" position and at the "altitude". After crossing the "fixIdent" position, AI will turn to runway heading and land. I don't think ATC ever considers alt1 or alt2 in a leg. It looks like MS has the IF leg of an approach set so alt1 is the procedure listed min alt for the leg, and alt2 is the alt at the FAF but I don't think that data is used by ATC (not sure on this though).scott s..

What does the Alt Desc setting in the approach editor mean? I figure PLUS and MINUS mean at or below the altitude setting under Alt1 and Alt2 Feet, which is what the ADE manual says, but what the heck does A, B, C, G, H, I, J, V and Space mean??? How would you know what to set there? It seems no one on the FSDeveloper website has made reference to this setting, but it does something I assume.I'm just trying to understand the appraoch code better so I can maybe tweak a few incorrect approaches in FS9.Thanks,Chris

I answered this question at the following linkhttp://www.fsdeveloper.com/forum/showthread.php?t=17369