Spit IIA Speed in game test

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Look under METAR and be advised it changes with conditions. It will vary from 597-600 depending on which site you check.

What I said....

The field elevation is under the METAR tab on the link.....

http://www.checkwx.com/wxmain/fullsite/EGKB

be advised it changes with conditions.

Of course it changes with conditions, wow!!

Your altimeter is just an aneroid barometer.

Readings are taken periodically. That reading is converted to sea level. To do that requires putting the raw data through some formula's that are not dead on accurate.

The actual pressure is generally not static for very long either and changes with the passage of time. Lapse rate is also not standard either.

If you read FAR 91.121, it plainly states the order of precedence you take in setting your altimeter. The station pressure takes precedence over the field elevation.

(1) Below 18,000 feet MSL, to—

(i) The current reported altimeter setting of a station along the route and within 100 nautical miles of the aircraft;

(ii) If there is no station within the area prescribed in paragraph (a)(1)(i) of this section, the current reported altimeter setting of an appropriate available station; or

(iii) In the case of an aircraft not equipped with a radio, the elevation of the departure airport or an appropriate altimeter setting available before departure; or

(2) At or above 18,000 feet MSL, to 29.92″ Hg.

http://www.gleim.com/aviation/faraim...afNum%3D91.121

Why? If everyone is at the same altimeter setting then you are on the same scale.

Setting the atimeter to field elevation is close to the altitude scale everyone is using but it is not dead on accurate.

The elevation will vary depending on when the readings were taken, where, and which formula's were used to and the standard of accuracy for all but the most busiest and largest of airports is within 10 feet.

If you set your altimeter to the pressure given on ATIS/ADIS then it will rarely be the exact same as the field elevation.