Set the altimeter in FS2004 using the B key or panel knob, choose QNH or 29.92 correctly, and fix wrong altitude or pressure-unit readings.
In Microsoft Flight Simulator 2004, press B to reset the altimeter to the simulator’s local altimeter setting. For a realistic manual setup, obtain QNH from ATIS or ATC, then turn the panel’s barometric-pressure knob until that value appears in the Kollsman window. Use 29.92 inHg or 1013.2 hPa above transition altitude.
How to set the FS2004 altimeter
The default B command is the quickest method, while the cockpit knob lets you enter a reported pressure exactly.
- Obtain the pressure setting. Tune the airport’s ATIS, AWOS or ASOS where available, or use the altimeter setting given by FS2004 ATC.
- Set it automatically. Press
B. FS2004 adjusts the standard altimeter variable to the local weather pressure. - Set it manually. Find the small adjustment knob on an analogue altimeter, or the control labelled
BAROon a glass or airliner panel. Use its mouse hotspots until the reported value appears. - Check the indication. On the ground, an altimeter set to local QNH should read close to the airport’s published elevation.
If B has been reassigned, use our reference for checking FS2004’s default keyboard assignments and locate the altimeter reset or set command.
Which pressure setting should you use?
Use the reported local QNH or altimeter setting below transition altitude, and standard pressure when flying at flight levels.
| Flight phase | Setting | Expected indication |
|---|---|---|
| On the ground or below transition altitude | Local QNH or reported altimeter setting | Altitude above mean sea level |
| Above transition altitude | 29.92 inHg or 1013.2 hPa | Flight level based on standard pressure |
| Descending through the transition level | Destination or regional QNH | Altitude above mean sea level |
American ATC usually calls the value an altimeter setting, while QNH is the common term elsewhere. For practical simulator use they serve the same purpose: setting the altimeter so it indicates elevation above mean sea level when on the ground.
When should you set 29.92 in FS2004?
Set 29.92 inHg, equivalent to 1013.2 hPa, after climbing through the applicable transition altitude and return to local pressure when descending through the transition level.
Do not assume the transition altitude is 18,000 feet everywhere. That applies in the United States, but other countries use different published altitudes. FS2004’s built-in ATC is simplified and does not reproduce every regional procedure reliably, so follow the procedure for the flight you are simulating.
Pressing B sets local weather pressure; it is not a substitute for selecting standard pressure at cruise. Above transition altitude, verify that the display actually reads 29.92, 1013 or STD, depending on the panel.
What if the panel uses hPa instead of inHg?
Make sure the pressure value and instrument use the same units. Standard pressure is 29.92 inHg or 1013.2 hPa, and the general conversion is hPa = inHg × 33.8639. A unit mismatch is one of the most common causes of a wildly incorrect altitude.
Why does the B key not set the altimeter correctly?
The B key can appear ineffective when its assignment has changed, a custom gauge ignores FS2004’s normal command, or the weather pressure has updated since the ATIS report.
- Changed assignment: Check the control assignments and restore the altimeter set command.
- Custom add-on panel: Use the panel’s own BARO or STD control. Complex aircraft may intercept or replace the standard simulator event; for that cockpit type, see how the Boeing 777’s BARO and standard-pressure controls work.
- Keyboard focus: Click inside the simulator window before pressing
B, particularly after using another program or pop-up window. - Changing weather: Obtain a fresh ATIS report and reset the altimeter after a weather update.
- Standard-pressure flight: Enter 29.92 or 1013 manually rather than allowing
Bto restore local QNH.
Why does the altimeter not match the airport elevation?
With local QNH selected, the altimeter should be close to the published field elevation, but small differences can result from rounded pressure reports, weather-station distance or add-on scenery elevation.
A large discrepancy usually means the wrong pressure or units have been entered. As a useful diagnostic, an error of 0.10 inHg produces roughly 100 feet of altitude error near sea level, while 1 hPa is about 27 feet. Also check that the instrument is not still set to standard pressure after descent.
The barometric altimeter is not a radio altimeter: it does not show height above the runway or terrain. On approach, it continues to indicate altitude above mean sea level when correctly set to QNH.