Learn to hold level flight and constant speed with attitude, power and trim, plus practical fixes for porpoising, drift and control problems.
To hold level flight and constant speed in a general flight simulator, level the wings, set a normal cruise attitude and power, then trim until the aircraft flies almost hands-off. Monitor indicated airspeed and altitude with a steady scan, make one small correction at a time, and wait for it to take effect.
This technique applies across general-purpose flight simulators. Level flight means no sustained climb or descent; it does not mean the nose must sit at zero degrees on the attitude indicator. The required pitch attitude changes with aircraft type, weight, speed and configuration.
What actually holds level flight and speed steady?
Stable level flight comes from balancing pitch attitude, power, trim and bank rather than controlling any one of them in isolation.
- Pitch attitude establishes the aircraft's flight path and stops a climb or descent.
- Power supplies the thrust needed to balance drag at the chosen speed.
- Trim removes sustained elevator input; it does not lock the aircraft to an altitude.
- Bank and coordination keep the lift acting vertically. In a bank, some lift is directed sideways, so an uncorrected turn can lead to altitude loss.
Any change in power, speed, flap, landing gear, propeller setting or weight distribution can disturb that balance. Adding power may also produce a pitch or yaw change, especially in a single-engine propeller aircraft, so hold the desired attitude while the aircraft settles and then retrim.
How do I hold level flight and constant speed step by step?
The most reliable method is to establish a stable configuration, set attitude and power, remove the control pressure with trim, and then correct only developing trends.
- Choose easy practice conditions. Start with a light trainer in calm weather, at a safe altitude and comfortably above stall speed. Disengage the autopilot and disable any piloting assistance that moves the controls for you.
- Set the cruise configuration. Retract gear, flaps and spoilers as appropriate, then use a sensible cruise power setting from the aircraft's checklist or documentation. There is no single throttle percentage that works for every aeroplane.
- Level the wings. Use the outside horizon or attitude indicator, and keep the slip-skid indication reasonably centred. Fix an unintended bank before chasing altitude or speed.
- Establish the level-flight attitude. Note where the nose sits against the horizon. Many aircraft fly level with the nose slightly above the horizon; forcing the attitude indicator to exactly zero can produce a descent.
- Stop the altitude trend. If altitude is steadily changing, make a very small pitch correction and then neutralise the control. Use the altimeter to confirm altitude and the vertical speed indication to detect the trend.
- Correct the speed with power. Once the flight path is stable, add a little power for a sustained speed loss or reduce it for a sustained speed gain. Hold the level-flight attitude while the new power takes effect.
- Trim away the pressure. If you are holding back pressure, apply nose-up trim in small increments; if you are holding forward pressure, apply nose-down trim. Gradually relax the controller and see whether the aircraft keeps the desired attitude.
- Scan and wait. Recheck attitude, altitude, vertical speed, airspeed, heading and power. Make one correction, allow the aircraft to respond, and only then decide whether another is needed.
A mistake we see constantly is adding a correction before the previous one has taken effect. This creates the familiar up-and-down porpoise. Simmers still learning coordinated, small control inputs can use our beginner guidance for controlling a flight simulator before returning to precision level-flight practice.
Which instruments should I scan in level flight?
Use the horizon or attitude indicator to control the aircraft, then cross-check performance instruments to confirm the result.
- Outside horizon or attitude indicator: immediate pitch and bank information.
- Altimeter: actual altitude, but not always the earliest warning of a developing deviation.
- Vertical speed indicator: climb or descent trend. A traditional VSI lags, while glass-cockpit trend displays may react more quickly.
- Airspeed indicator: whether speed is stable, increasing or decreasing.
- Heading indicator: unintended turns that may reveal a slight bank.
- Engine instruments: RPM, manifold pressure, torque, N1 or another indication appropriate to the aircraft.
Do not stare at the altimeter or airspeed indicator and react to every small movement. If the aircraft is 30 feet from the target but no longer climbing or descending, it needs a gentle return rather than a large pitch input. When there is no visible horizon, building a disciplined IFR instrument scan is the skill that prevents fixation on one gauge.
Should I hold indicated airspeed or groundspeed?
Hold indicated airspeed, or the appropriate Mach number in a faster jet at altitude, rather than GPS groundspeed.
Headwinds and tailwinds change groundspeed without necessarily changing the aerodynamic condition of the aircraft. True airspeed also increases relative to indicated airspeed as air density falls, so a higher true airspeed at altitude does not by itself mean the aircraft is accelerating.
Does pitch or power control speed in level flight?
For ordinary cruise flight, use pitch attitude to arrest the vertical trend and power to remove a sustained speed error while holding altitude.
All the controls remain coupled. Raising the nose initially reduces speed, lowering it increases speed, and a power change can alter pitch. The practical objective is to restore equilibrium: lift balances weight, thrust balances drag, altitude stops changing and airspeed settles.
Slow flight and approaches can require a different emphasis, particularly on the back side of the drag curve. There, pilots often use pitch primarily for airspeed and power primarily for flight path. Follow the technique specified for that aircraft and phase of flight rather than trying to apply one slogan everywhere.
Why does my aircraft keep climbing, descending or porpoising?
Repeated deviations usually come from an incorrect attitude or power setting, poor trim, overcontrol, turbulence or unwanted controller input.
| Symptom | Likely cause | Practical fix |
|---|---|---|
| Altitude slowly increases | Nose slightly high, excess power or nose-up trim | Lower the nose enough to stop the trend, check power and retrim after the speed stabilises |
| Altitude slowly decreases | Nose slightly low, an unnoticed bank or insufficient power as speed decays | Level the wings, restore the correct attitude, adjust power if needed and retrim |
| Airspeed falls in level flight | Too little power or extra drag | Add a small amount of power and check gear, flaps and spoilers |
| Airspeed rises in level flight | Excess power | Reduce power slightly while holding altitude, then wait for the new speed |
| Repeating climb and descent | Chasing the instruments or making large inputs | Use a smaller pitch correction, neutralise the control and wait |
| Constant push or pull required | Aircraft not trimmed for its present speed and power | Hold the required attitude first, then trim away the pressure |
| Roll or pitch movement with hands off | Axis noise, duplicate bindings, an assist or active automation | Inspect every controller assignment and watch the simulator's input display for movement |
| Difficult to hold in gusts | Turbulence rather than poor trim | Correct sustained trends, not every short-lived displacement |
If the controls feel twitchy, add only enough dead zone to remove genuine axis noise. Excessive dead zone creates a large inactive area followed by an abrupt response. A gentler response near the centre can help, but it should not conceal a faulty controller or duplicated assignment.
Why will trim not hold the aircraft steady?
Trim will only produce stable flight after attitude, power, speed and configuration have settled.
On a real aircraft, trim removes physical control pressure. Most spring-centred joysticks and yokes do not move to a new position as trim changes, so the simulation instead shifts the virtual elevator neutral point. Hold the desired attitude, add trim in small increments and progressively relax the controller towards its physical centre.
- Trim changes by too much: shorten the button press or reduce trim response where the simulator provides that adjustment.
- Trim appears to move by itself: look for autopilot operation, auto-trim assistance, a stuck switch or duplicate trim bindings.
- The aircraft was stable but drifts after a change: retrim after changing power, speed, flap, gear or propeller setting.
- The nose jumps as the control is released: you may be trimming while still holding too much joystick or yoke displacement.
Fine trim is difficult when one button press produces a large pitch change. Our guide to tuning trim sensitivity and control response explains how to make precise inputs without masking other control problems.
Does the technique change between light aircraft and jets?
The same attitude-power-trim relationship applies to every aircraft, but response time, control sensitivity and the appropriate speed reference change.
| Aircraft type | What changes | Best technique |
|---|---|---|
| Light trainer | Quick response, noticeable propeller effects and sensitivity to rough inputs | Use fingertip-sized control movements and trim frequently after power changes |
| Turboprop | Strong power response and additional propeller controls | Use the aircraft's recommended cruise torque and propeller setting, then allow it to settle before retrimming |
| Jet | Greater inertia and delayed thrust response | Make small thrust changes and wait; use the scheduled indicated airspeed or Mach target rather than chasing groundspeed |
Can autopilot hold both altitude and speed?
An autopilot can hold altitude with pitch, but it will not necessarily hold speed unless the aircraft also has an active autothrottle or a mode specifically controlling speed.
In many light aircraft, altitude hold controls pitch while the pilot still moves the throttle to maintain airspeed. In an aircraft with autothrottle, the system can usually manage thrust for a selected speed when the correct mode is engaged. Do not fight an engaged autopilot with manual trim; disconnect it, stabilise the aircraft and retrim before resuming hand flight.
The exact behaviour depends on the selected vertical and thrust modes, particularly during climbs and descents. Our explanation of how autopilot altitude hold, power and airspeed work together covers the distinction without replacing the need to understand manual trim.
The useful memory rule is level the wings, set attitude, set power, trim, scan and wait. If the aircraft is still moving away from the target, correct the trend with one small input rather than chasing the displayed number.