Not to say there aren’t issues with some glide slopes being wrong in the sim. But It’s not unusual for an ILS GS to not match up with a visual glide slope indicator (VGSI), either VASI or PAPI, even if they have the same slope gradient. I’ve seen IFR GS’s both above and below the VGSI. That’s because the GS signal is not always broadcast to guide to the same touchdown point at the VGSI. The only way to see that ahead of time is to look at the IFR approach chart.
Most of the IFR charts I have are PDF’s, so I can’t post them here. But you can go to the FlightAware site and pull down the IFR charts for almost all airports in the U.S. (and some others). As an example, pull down the chart for KSEA, ILS/LOC 16R. You’ll see a comment on the profile view that says “VGSI and ILS glidepath not coincident. VGSI angle 3.00/TCH 69”, and below the profile view of the approach it says “GS 3.00/TCH 55”. TCH is Threshold Crossing Height. If you’re in a position to watch the VGSI on an IFR approach, you’ll find The difference in crossing height becomes more and more obvious as you approach the runway and the VGSI will show high, and sometimes low, depending on the difference in crossing height and whether the ILS TCH is higher or lower than the visual TCH.
Regards
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