Why does an aircraft stall and lose altitude, and how do you recover?

An aircraft stalls when its wing exceeds the critical angle of attack, causing airflow separation, loss of lift and increased drag. It loses altitude because lift no longer balances weight. Recover by reducing angle of attack, applying power as appropriate, controlling yaw and roll, then rebuilding airspeed before smoothly returning to the flight path.

What causes an aircraft to stall?

In Aviation & Real-World Flying, an aerodynamic wing stall is caused by excessive angle of attack, not by one universal airspeed or a particular pitch attitude. Once the wing passes its critical angle, separated airflow reduces lift, raises drag and may make the controls less effective.

An aircraft can therefore stall nose-high, level or nose-low. Low airspeed makes a stall more likely because the pilot must normally increase angle of attack to maintain lift, but speed is an indirect factor. Our explanation of how pitch control changes angle of attack covers this relationship in more detail.

Weight, bank angle, manoeuvring load, flap configuration, icing and turbulence affect the indicated speed at which the critical angle is reached. In a coordinated level turn at 60 degrees of bank, for example, the load factor is about 2g and stall speed rises to roughly 1.41 times its 1g value. Published VS0 and VS1 figures are useful references, but our guide to aviation V-speeds and stall references explains why they are not fixed limits for every condition.

Why does a stalled aircraft lose altitude?

A stalled aircraft descends because the wing is no longer producing enough lift to balance its weight. Increased drag also drains airspeed, while reduced control effectiveness can allow the nose or a wing to drop.

The aircraft may continue climbing briefly through momentum after the stall begins, but it cannot maintain that flight path. Lowering the nose during recovery may initially increase the descent rate; that height is being exchanged for the airflow and energy needed to restore controlled flight. Trying to preserve altitude by pulling back usually deepens the stall.

How do you recognise an approaching stall?

An approaching stall is recognised from a combination of high angle of attack, deteriorating control response and the aircraft's warning systems.

• Stall warning: a horn, light, voice alert, stick shaker or angle-of-attack indication, depending on aircraft type.
• Aerodynamic buffet: disturbed airflow may shake the airframe or controls before the full stall.
• Poor control response: the aircraft feels soft or reluctant to respond, particularly in pitch or roll.
• Uncommanded movement: a wing drop, yaw, pitch break or rapidly increasing sink rate.
• Energy cues: decreasing airspeed combined with increasing back pressure, nose-up trim or load factor.

Not every aircraft gives every cue, and icing or contamination can alter the warning margin. A stall should be corrected at the first reliable indication rather than allowed to develop fully.

How do you recover from an aircraft stall?

The central action in aircraft stall recovery is to reduce angle of attack until the wing is flying again. Exact control movements, power settings and configuration changes vary by type, so the approved aircraft flight manual or pilot operating handbook takes precedence.

1. Take control. Disconnect the autopilot or autothrottle if it is engaged and interfering with recovery, following the aircraft's approved procedure.
2. Reduce angle of attack. Release back pressure and lower the nose enough to remove the stall warning. The movement may be small or pronounced depending on the aircraft and severity of the stall. Do not fight an activated stick pusher.
3. Control yaw and roll. If a wing drops, continue reducing angle of attack and use coordinated controls appropriate to the aircraft. Large aileron input while the wing remains stalled can worsen the roll, while abrupt rudder can initiate a spin.
4. Apply power as appropriate. Use available thrust smoothly while controlling any associated pitch, roll or yaw. Power helps rebuild energy, but power alone does not unstall a wing if the angle of attack remains excessive.
5. Reduce unnecessary drag. Retract speed brakes or spoilers when the procedure calls for it. Do not retract flaps abruptly; the resulting loss of lift can increase the sink rate or cause another stall.
6. Rebuild speed and recover. Once the stall warning has ceased and adequate flying speed has returned, smoothly recover to the intended flight path. Avoid pulling so hard that the aircraft exceeds the critical angle again.

This sequence describes a conventional wing stall. Iced-tailplane stalls, deep stalls and developed spins can require different control actions, so they must be handled using aircraft-specific procedures and training.

Why does the aircraft stall again during recovery?

A secondary stall happens when the pilot raises the angle of attack too aggressively before sufficient airspeed has returned. A mistake we see constantly in simulators is pulling hard to stop the altitude loss as soon as the nose starts to descend.

• Pulling back before the stall warning has cleared.
• Adding full power without controlling the resulting pitch or yaw.
• Leaving strong nose-up trim or automation engaged.
• Using large aileron inputs to lift a dropped wing while it remains stalled.
• Retracting flaps suddenly instead of cleaning up in stages.
• Fixating on altitude rather than restoring controlled airflow first.

If automation repeatedly raises the nose, loses speed and then pitches down, the underlying problem may be the selected vertical mode, an unrealistic climb demand or poor trim management. Our advice on diagnosing autopilot pitch and altitude oscillations addresses that cycle.

How much altitude is lost during stall recovery?

There is no fixed altitude loss for an aircraft stall recovery. Entry attitude, airspeed, load factor, configuration, power, aircraft design and pilot response all affect the result.

A prompt recovery from an incipient stall may lose little height; a fully developed stall, steep bank, delayed response or secondary stall can lose far more. Any published demonstration figure applies only to stated test conditions and is not a guarantee. Near the ground, immediate angle-of-attack reduction and stall prevention are critical because there may not be enough height for recovery.

Does a wing drop mean the aircraft is spinning?

No; a wing drop can occur during a stall without becoming a developed spin. A spin requires a stalled condition combined with sufficient yaw to produce sustained autorotation.

Reducing angle of attack promptly and avoiding uncoordinated control inputs helps prevent that transition. If autorotation becomes established, use the approved spin-recovery procedure for that aircraft; some aircraft are not approved for intentional spins, and a generic stall recovery is not a substitute for type-specific instruction.