Pressure Changes

[Gnomus1]

Hi there,
a couple of days ago I was flying from EDDF to EGLL, real world weather turned on. I am also using FSUIPC. Well anyway, it was a bloody scary flight, too much turbulence for my taste ;-). When I was doing my ILS approach, ATC cleared me and I had to maintain 2100 until established on the localizer. I also calibrated my altimeter correctly to the value ATC gave me. When I intercepted the glideslope, I was wondering why I was so ##### low. Pressed "B", and suddenly I was at 1600 and not 2100 any more!!! What can you do against those huge pressure changes between two close regions, shouldn't FSUIPC smoothen them anyway? Or is there a way to make ATC give you the correct QNH value for the destination airport?

Gnomus

[Simon Evans]

Assuming you were using Real Weather, there are often gaps in the coverage and FS extends the radius of one reporting station to cover the gap. FS Meteo seems to offer a much better solution for the dedicated realweather flyer.

A better solution than successive extend would be to `average` the results between successive reporting stations as a gradual decline in pressure could become most marked (as here) which is extremely unlikely in the real world.

FSUIPC can slow the rate of change, but if the actual pressure differential is great then even Mighty FSUIPC can only turn a cliff into a very steep hill...

From a flying-in-FS point of view I s'pose you could try tuning into the ATIS from a long way out and pre-setting the pressure. As long as you're not flying in mountainous areas or under ATC control, the relative height of the aircraft AGL is pretty unimportant. NOTE: It's different in the real world!



Simon Evans