Microsoft KB Archive/264616

= FS2000: Differences Between True Air Speed and Indicated Air Speed =

Article ID: 264616

Article Last Modified on 10/6/2003

-

APPLIES TO


 * Microsoft Flight Simulator 2000 Standard Edition
 * Microsoft Flight Simulator 2000 Professional Edition

-



This article was previously published under Q264616



SUMMARY
This article describes true air speed, indicated air speed, and how to derive true air speed from indicated air speed based on altitude.



True Air Speed
True air speed is the actual speed at which an aircraft moves from one point to another. True air speed can be affected by the altitude of the aircraft, but in most cases the effect is minimal because most aircraft fly at a maximum altitude of seven to nine miles. Some large aircraft can fly at higher altitudes. For example, the Concorde can fly at a maximum altitude of approximately eleven miles.

Indicated Air Speed
The air speed displayed on the Air Speed Indicator on the instrument panel in your aircraft is the indicated air speed. Indicated air speed is the speed at which an aircraft moves through the air, and it can be affected significantly by altitude and wind direction.

The Air Speed Indicator works by comparing the air pressure inside the Pilot Tube to the air pressure inside the aircraft cabin. The Pilot Tube is a hollow probe that points directly forward into the oncoming air.

Changes in altitude can affect indicated air speed. As the altitude of the aircraft increases, the air pressure in the Pilot Tube decreases, causing the indicated air speed to decrease.

Assuming no effects from wind, the following table lists the true air speed in nautical miles-per-hour (knots) for an aircraft traveling at 400 knots at altitudes between 1000 feet and 25000 feet.

Additional query words: msgame fs2k flightsim fsim airspeed mph

Keywords: kbinfo kbref KB264616

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.