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Guest waterspout

QNH at destination

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Guest waterspout

In order to do an IFR letdown it is necessary to get the destination aerodrome QNH or QFE before starting the procedure. In fs2004, using dynamic RW weather, this information is available through the aerodrome ATIS if it has one. Some a/d's, however, do not have ATIS.I have found a way of getting the wind vector from the met map in fs, but not the pressure.The data must be available for it to appear in ATIS - is there any other way when commencing a let down to get hold of the a/d pressure?

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Guest RonB49

>In order to do an IFR letdown it is necessary to get the destination aerodrome QNH or QFE before starting the procedure.Actually, what you need is the local pressure where you are. This way, as you (and all other traffic) descend through the transition altitude, then you'll all be setting your altimeters to the same numbers. If each plane sets their altimeter to the barametric pressure at their various destinations, they'll all be different. Therefore, the first ATC facility (and all subsequent facilities) that you contact after descending below the transition altitude recites the local pressure to you.Now, if you're flying VFR and talking to no one, then you have another problem; you'll need to find an ATIS or an AWOS. R-

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Guest Traffic

Its not very realistic but you can also press 'B' which sets the current QNH, whatever it may be, as an altimeter setting for you.You should keep pressing 'B' occasionally as you move through areas with different surface pressures.

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Guest waterspout

I'm aware of transition altitude, regional QNH's etc. You still need the aerodrome pressure before making an approach. If you examine an IFR approach plate you will sometimes see heights given to the nearest foot*. The only way you can fly to that degree of accuracy is with the a/d QNH or QFE set. Even in VFR you need either the QFE or QNH before joining the circuit.I don't quite understand why so many simmers seem to be unaware of the need for this.*The procedure for LLZ/DME to r/w 09 at Liverpool, for example, requires a descent to 1609' on the outbound leg.

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Guest waterspout

Thanks Rob. That's the most useful reply I've had so far.

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