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Tim Arnot

Altimeter in FSX

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What's the correct way to use the Altimeter in small aircraft in FSX?Say I'm inbound to a small airfield under VFR in a Cessna or suchlike. In the UK when you're entering the circuit (traffic pattern) as I understand it you use a QFE altimeter setting -- which effectively means the altimeter shows 0ft on the ground at the airport. This is important because I want to be turning finals at around 600feet above the runway. Now in FSX the world runs to US rules (!) so I don't get a QFE altimeter setting from the airfield -- and its not in millibars. Even so, what should I do to maximise realism. Should I add the airfield height to the altimeter as I approach, and when should I do this? Thoughts please. Also -- if they ever improve ATC could they please build in a read-over of the wind speeds on the runway when you get landing clearance. That's what happens in real life. Can never seem to spot the windsock from the circuit.

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Yes but here in the UK that's QFE when flying small aircraft VFR -- which FSX ATC being American, doesn't give you. This from Wikipedia:Student pilots sometimes think of QFE as "Q Field Elevation" to help them remember its meaning.ATC will update pilots with the QFE when necessary. A typical radio conversation might go:Pilot: Golf Whiskey Alpha Charlie Foxtrot, requesting taxi clearance for local VFR. ATC: Golf Charlie Foxtrot, taxi to Alpha for two-five right hand, QFE niner-niner-eight millibars. Pilot: To Alpha, two-five right, QFE niner-niner-eight, Golf Charlie Foxtrot. In most parts of the world, QFE is given in millibars (or hectopascals, which is the same-sized SI unit). Whilst the Royal Air Force (RAF) and some European private pilots still use QFE, it is largely obsolete in commercial aviation, where QNH is preferred for take off and landing (and where sophisticated radio aids can be used during landing). >>>>In general aviation, QFE is routinely used during take off and landing (where the eyeball tends to be used) and when flying in the circuit. The exception to this is in the USA and Canada, where QFE is rarely used, the most common practice being to use QNH (known simply as the "altimeter setting") for all operations below the transition altitude.

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"Forget you ever heard of QFE and use QNH. Internationally QFE is an anachronism and not used."Not here in the UK at small airfields it aint. QFE is well used by PPLs. I reckon the answer to my question is to set the alt. to zero on the ground, leaving it like that for taking off, flying circuits etc.When leaving the circuit and talking to enroute ATC, reset to the QNH given. When landing, simulate the QFE by turning the Alt. knob up by however many feet the airfield runway is at.

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Irrespective of local real world usage, in FS it is always QNH that is given by ATC... ;)

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In the US, you set it to the closest reporting station. At a class D or above, you can get the altimeter setting from ATIS. At a smaller airport, you could use ASOS/AWOS, or call up the FBO UNICOM and ask.It is set to the current pressure at sea level, not field elevation.So when I fly to Meriden for example, I get the altimeter from AWOS (usually I don't bother since I set it 15 miles back on takeoff- but anyway). Then I figure out pattern elevation (1000 feet above field elevation rounded down so 1000+103=1100). Then I figure out the altitudes I need. 600 feet would be 700 on the alt. 700 would be 800 (normally that is when I turnout after takeoff, but Meriden has noise abatement so I climb to 1000 AGL before turning, which is 1100).I hope that includes the answer you are looking for :) The babbling is for my own sake.*To clarify, on the ground at Meriden, the altimeter SHOULD read field elevation- i.e. 103 feet if set correctly.

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If you're just flying 'local', or doing circuits and will be returning to the same airfield, the easiest way to set QFE is simply to adjust the altimeter on the ground to read 0 feet. Otherwise set to the QNH. When approaching another airfield, either ADD the airfield elevation to your altitude (e.g. if the airfield is at 500ft, fly the circuit at 1500ft QNH), or turn the dial to SUBTRACT the airfield elevation and give you the QFE.Your suggestion to turn the knob UP will give you an incorrect reading. Think about it: QFE will always be lower (unless the airfield is at or below sea level!)

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