Use altitude hold in FS2004's default Boeing 737, 747 and 777 with the correct MCP sequence, vertical-speed settings, capture checks and fixes.
In FS2004’s default Boeing 737, 747 and 777, dial the required altitude into the MCP, stabilise at a safe airspeed, engage the autopilot master or CMD, then select ALT or ALT HOLD. Set a sensible vertical speed for the climb or descent; the autopilot should capture the selected altitude and reduce vertical speed to zero.
What is the correct FS2004 Boeing altitude-hold sequence?
The stock Boeing panels share the same basic FS2004 autopilot logic, although their controls look slightly different. They model a simplified system rather than a complete Boeing flight-management and VNAV installation.
- Stabilise the aircraft. Hand-fly away from the ground, establish a safe airspeed and trim out any strong pitch pressure. Do not engage the autopilot during the take-off roll.
- Select the target altitude. Turn the altitude selector until the required altitude appears in the MCP window. Turning this knob alone does not engage altitude hold.
- Set thrust and airspeed. Apply enough thrust for the intended climb, level flight or descent. If using autothrottle, arm it and engage the appropriate speed mode separately.
- Engage the autopilot. Press the AP master or CMD control. The flight director by itself only displays guidance and does not move the controls.
- Engage ALT or ALT HOLD. The aircraft should begin moving towards the selected altitude. Use the V/S control to choose a reasonable climb or descent rate rather than demanding more performance than the aircraft can provide.
- Check the capture. As the aircraft approaches the target, vertical speed should decrease and the aeroplane should level off. Confirm that ALT remains active and that the altitude has stabilised.
For the default assignments, Z toggles the autopilot master and Ctrl+Z toggles altitude hold. The keyboard command does not choose the correct altitude, thrust or climb rate for you; our FS2004 autopilot and flight-control shortcut list covers the other stock assignments.
What do the Boeing autopilot controls actually do?
The altitude selector, altitude mode and vertical-speed control have separate jobs. Confusing them is the main reason the aircraft either stays level or flies through the intended altitude.
| Control | Function in the default Boeing jets |
|---|---|
| Altitude selector | Sets the target altitude; it does not engage the autopilot. |
| ALT or ALT HOLD | Commands capture and then holds the selected altitude. |
| V/S | Sets the climb or descent rate. Used alone, it may carry the aircraft through the target. |
| AP master or CMD | Allows the autopilot to control the aircraft. |
| Flight director | Displays steering cues but does not fly the aircraft without CMD engaged. |
| A/T and speed mode | Control thrust and speed separately from altitude hold. |
Our explanation of altitude selection, capture and hold modes gives more detail on how these stages relate to one another.
How do I hold the altitude I am already flying?
Level the aircraft, set the altitude window to the present indicated altitude, engage the autopilot master and then select ALT HOLD. Reducing the climb or descent rate before engagement prevents an abrupt correction or overshoot.
Check the altitude window first. If it still contains an old cruise or approach altitude, the aircraft may immediately climb or descend towards that value instead of maintaining the altitude you expected.
Why does altitude hold climb, dive or miss the target?
Unexpected movement usually comes from an incorrect target, an inactive mode or insufficient aircraft performance. Check these common causes in order:
- It heads towards the wrong altitude: the altitude selector still contains an earlier setting.
- Nothing happens: CMD or the autopilot master is off, or only the flight director is active.
- It flies through the target: V/S is active but ALT capture is not selected. Recheck the ALT button or mode indication.
- A climb becomes a stall: the selected vertical speed is too high for the available thrust and airspeed. Reduce V/S, increase thrust as appropriate and disconnect the autopilot if a manual recovery is required.
- A descent causes overspeed: reduce the descent rate or manage thrust and drag; altitude hold provides no automatic overspeed protection.
- It oscillates or porpoises: return the simulator to normal time acceleration, stabilise the aircraft and make sure joystick noise or continuous control input is not fighting the autopilot.
If ALT still refuses to capture after the sequence is correct, work through our focused FS2004 altitude-hold troubleshooting checks.
Does altitude hold control airspeed and thrust?
No. Altitude hold primarily commands pitch, while thrust and airspeed remain separate responsibilities unless autothrottle and speed mode are engaged. A default Boeing can obey an excessive climb command until it loses too much airspeed, so always monitor the airspeed indicator and reduce vertical speed as performance falls at higher altitudes.