Learn how pilots slow an airliner before landing using thrust, speed brakes, flaps and gear—and what happens when an approach is too fast.
Pilots slow an airliner before landing by managing energy: they reduce thrust, level or shallow the descent when needed, use speed brakes to shed excess energy, then extend flaps, slats and landing gear within their speed limits. The aircraft must reach its calculated approach speed and be fully configured by the operator’s stabilised-approach gate.
In real-world airline operations, slowing down is a planned sequence rather than one action. The crew must balance altitude, airspeed, distance remaining, wind, air traffic control restrictions and the aircraft’s configuration limits.
Why does reducing thrust not always slow an airliner?
An airliner descending at idle thrust can maintain its speed or even accelerate because altitude is being converted into speed. A steep descent makes this more pronounced, especially in a clean configuration with the landing gear and flaps retracted.
To decelerate efficiently, pilots usually reduce the descent rate or level off while keeping the thrust low. This is why being both high and fast is troublesome: descending and slowing compete for the aircraft’s available energy. The crew may need more track miles, an earlier descent or additional drag.
What controls slow an airliner before landing?
Pilots combine thrust changes, flight-path adjustments and drag-producing devices according to the aircraft’s procedures.
| Method | When it is used | Main limitation |
|---|---|---|
| Reduced thrust | The normal first step when there is enough distance | A steep descent may prevent meaningful deceleration |
| Shallower descent or level flight | To convert less altitude into speed and let drag slow the aircraft | May require clearance or extra distance from air traffic control |
| Speed brakes | To correct excess speed or altitude temporarily | Use with flaps may be restricted, and deployment can cause buffet |
| Flaps and slats | In stages as the aircraft approaches its scheduled configuration speeds | Each setting has a maximum extension speed |
| Landing gear | Later in the approach when substantial, predictable drag is needed | Gear extension has speed limits and increases noise and fuel use |
Autothrottle does not replace energy management. It reduces or increases engine thrust to hold the commanded speed, but the crew still selects or accepts the speed targets and configures the aircraft. Our explanation of how airliner autothrottle controls thrust covers why it may add power again once the selected speed is reached.
In what order do pilots reduce speed and configure?
The exact sequence comes from the airline’s procedures and the aircraft type, but a normal approach follows this pattern:
- Plan the deceleration. The crew checks the arrival, runway, wind, speed restrictions and expected distance to touchdown. The flight-management system may display a deceleration point, but it still needs monitoring.
- Reduce thrust and lower the target speed. If the aircraft is on a suitable descent path, idle or low thrust begins the deceleration. Air traffic control speed instructions must still be followed unless the crew reports that compliance is not possible.
- Add speed brake if necessary. Flight spoilers increase drag without requiring an early landing configuration. They are normally retracted once the excess energy has been removed.
- Select flaps in stages. Each flap selection is made below its maximum permitted extension speed and near the scheduled manoeuvring speed. The flap-limit marking is a limit, not a target to chase.
- Lower the landing gear and select landing flap. Gear drag helps stabilise both speed and descent rate. For more detail, see how extending landing gear changes aircraft drag.
- Settle at approach speed. The aircraft should be on the correct path, in landing configuration and close to its calculated VREF or VAPP with stable thrust. Approach speed depends on weight, flap setting and wind correction rather than one universal number, as shown by this Airbus A320 approach-speed example.
The same logic is shown in our practical Boeing 737 descent and configuration sequence, although actual flap speeds and checklist timing must come from the relevant operating procedure.
Can pilots use speed brakes with flaps extended?
Some airliners permit limited speed-brake use with certain flap settings, while others impose restrictions or discourage the combination. The approved procedure for the aircraft type always takes precedence.
Speed brakes are best treated as a temporary correction, not as the normal way to control final-approach speed. Extending them can change lift, pitch and buffet levels. A mistake we see in simulators is leaving the flight speed brakes deployed instead of retracting them and then correctly arming the ground-spoiler system for touchdown.
What happens if the aircraft is too high or too fast?
The crew should correct a high-energy approach early rather than force the aircraft onto the runway. Available actions include requesting extra track miles, reducing the descent rate, levelling temporarily, using speed brakes or lowering the gear earlier within its limits.
Trying to dive towards the glide path while simultaneously slowing is a common failure. Another is extending flaps or gear above their placarded speeds; being late does not justify exceeding an aircraft limitation.
By the stabilised-approach gate, the airliner should be correctly configured, on the required path and within the operator’s speed and descent-rate tolerances. Many operators use a gate around 1,000 feet above aerodrome elevation, while some procedures permit a lower gate in visual conditions. If the approach is not stable by the applicable gate, the proper response is a go-around.
Do pilots use wheel brakes or reverse thrust before touchdown?
No. Wheel brakes cannot slow an airborne aircraft, and normal airliner operations do not use reverse thrust before touchdown. Before landing, drag comes from the aircraft’s flight path, speed brakes, flaps, slats and landing gear.
After touchdown, the ground spoilers deploy to remove lift and place more weight on the wheels. Wheel braking and reverse thrust then help decelerate the aircraft during the landing roll.