Slow flight is maneuvering the airplane at an airspeed so low that any further increase in angle of attack, increase in load factor, or reduction in power would set off the stall warning, while you hold altitude, heading and bank without letting that warning sound. It teaches the feel of the low-speed, high angle of attack regime you pass through on every takeoff and landing. On the Private Pilot checkride it is ACS Task VII.A, completed no lower than 1,500 feet AGL with an airspeed tolerance of +10/-0 knots.
Part of our Flight Maneuvers guide. This page is educational and is not a substitute for instruction from a certificated flight instructor or for your airplane’s POH.
What slow flight teaches
Takeoffs, departures, approaches and landings all happen at low airspeed close to the ground. Slow flight lets you explore that regime at a safe altitude. The FAA Airplane Flying Handbook (FAA-H-8083-3C) sets out the goals: understand the aerodynamics of slow flight in different configurations, recognize the airplane’s cues, maneuver with smooth, coordinated inputs without a stall warning, and correct promptly if one occurs. Stall training builds directly on it, covering the span from the stall warning to the stall itself.
The regulations require it early. Before solo, 14 CFR 61.87(d)(9) requires training in flight at various airspeeds from cruise to slow flight, and slow flight and stalls is one of the areas of operation for the private pilot certificate under 61.107(b)(1).
The ACS standard: Task VII.A
Maneuvering During Slow Flight is Task A of Area of Operation VII, Slow Flight and Stalls, in the Private Pilot for Airplane Category ACS (FAA-S-ACS-6C). The skill elements are:
- Clear the area.
- Select an entry altitude that allows the task to be completed no lower than 1,500 feet AGL (3,000 feet AGL in a multiengine airplane).
- Establish and maintain an airspeed at which any further increase in angle of attack, increase in load factor, or reduction in power would result in a stall warning, such as aircraft buffet or the stall horn.
- Fly coordinated straight-and-level flight, turns, climbs and descents, with the airplane configured as the evaluator specifies, without a stall warning.
- Maintain the specified altitude ±100 feet, heading ±10°, airspeed +10/-0 knots, and specified angle of bank ±10°.
Two details trip people up. First, the airspeed tolerance is one-sided: you may drift up to 10 knots fast, never slow. Second, the stall warning should stay quiet. An ACS appendix recognizes that turbulence can cause a momentary activation of a warning such as the stall horn, and that is not unsatisfactory if you recognize it and promptly correct. Continual deviation, no correction, or failing to notice it is.
On configuration, the task objective describes slow flight in cruise configuration, the skill element leaves the configuration to the evaluator, and the AFH notes slow flight is typically performed and evaluated in the landing configuration. Practice it clean, with partial flaps and in the full landing configuration so any request feels familiar.
| Item | Standard |
|---|---|
| Altitude floor | Complete no lower than 1,500 ft AGL (single-engine) |
| Airspeed | Just above the stall warning, +10/-0 kt |
| Altitude | Specified altitude ±100 ft |
| Heading | Specified heading ±10° |
| Bank | Specified bank ±10° |
| Stall warning | None while maneuvering |
Why the airplane feels different
At slow flight speeds the wing works at a high angle of attack, close to the critical angle at which it stalls. Our stalls and angle of attack guide explains that relationship. In the cockpit it shows up five ways:
- Mushy controls. Less airflow over the control surfaces means larger control movements for the same response. Pilots call the feel sloppy or mushy.
- More power to fly slower. Slow flight is well below the speed for minimum drag (L/DMAX), on the back side of the power curve, where it takes more power, not less, to fly slower. Pitch becomes the more effective control of airspeed, and power the effective control of the flight path.
- Speed instability. Below L/DMAX, if turbulence knocks off a few knots, the airspeed can keep decaying unless you lower the nose or add power.
- Left yaw. At high power and low airspeed, torque, slipstream and P-factor yaw the nose left, so you hold right rudder, and more of it the closer you are to the stall. See left-turning tendencies.
- Turns cost margin. Banking increases load factor, which raises the stall speed, so a turn in slow flight needs more power to hold altitude and brings the warning closer. Weight, center of gravity and flap setting move the stall speed too, which is why the AFH stresses that the published stall speed applies only to unaccelerated, coordinated flight at one weight and CG (see our weight and balance guide).
The ACS also asks you to manage environmental risks such as turbulence and high density altitude, both of which shrink your margin at low speed.
How to fly slow flight, step by step
- Clear the area and pick an altitude that keeps the whole maneuver at or above 1,500 feet AGL, or higher if the manufacturer recommends it.
- Reduce power and hold altitude. Bring the power back from cruise and raise the nose gradually to hold altitude as the airspeed decays. Listen for the change in the sound of the airflow.
- Configure as briefed. If flaps are specified, run your before-landing checks and extend them only within their operating speed limit (see V-speeds).
- Add power at the target speed. As you approach the target airspeed, add power to hold altitude and trim off the back pressure. Left trimmed for cruise, the airplane needs strong back pressure, which makes precise control difficult.
- Hold it. Pitch for airspeed, power for altitude, right rudder to keep the ball centered, and eyes outside with regular instrument cross-checks.
- Maneuver. Make level turns (adding power to hold altitude), straight climbs and climbing turns of about 20° of bank, and straight and turning descents, all with smooth inputs. Abrupt inputs, such as raising the flaps suddenly, can cause a stall.
- Recover. Add power, then apply forward pressure to reduce the angle of attack and hold altitude as the airspeed increases. Stay coordinated, retract the flaps as the airspeed builds while anticipating the change in angle of attack, and retrim.
Finding your slow flight airspeed
There is no single number. The target is just above the stall warning for the configuration you are in, and the AFH suggests 5 to 10 knots above the 1G stall speed as a good target. To find it in your airplane, the AFH describes slowing to the stall warning in the desired configuration, lowering the nose slightly to eliminate the warning, adding power to maintain altitude, and noting the airspeed. Expect a different number clean and with flaps.
Treat the stall warning as a floor, not a target. If it chirps, lower the nose slightly or add a little power right away, then settle back at your speed. Recognizing the warning and correcting promptly is exactly what the examiner wants to see.
Common errors
The AFH lists these common errors in slow flight:
- Failure to adequately clear the area.
- Too little back pressure as power is reduced, losing altitude, or too much, climbing and then losing airspeed rapidly.
- Insufficient right rudder to compensate for left yaw.
- Fixation on the flight instruments.
- Failure to anticipate changes in angle of attack as flaps are extended or retracted.
- Inadequate power management.
- Inability to divide attention between airplane control and orientation.
- Failure to trim the airplane properly.
- Failure to respond to a stall warning.
Where slow flight leads
Slow flight is the doorway to stall training, which carries the same setup past the warning to the stall itself. Once slow flight feels routine, move on to power-on and power-off stalls. The low-speed feel you build pays off in every flare and in short-field approaches, and the load factor lesson returns in steep turns.
Study tools
What you'll need
The FAA handbooks and the ACS that cover slow flight, all from PilotMall.com.
Frequently asked questions
What is slow flight in aviation?
Slow flight is flying at an airspeed where any further increase in angle of attack, increase in load factor, or reduction in power would cause a stall warning. You maneuver there, holding altitude, heading and bank, without letting the warning sound.
Should the stall horn sound during slow flight on the checkride?
No. ACS Task VII.A requires straight-and-level flight, turns, climbs and descents without a stall warning. The ACS notes that a momentary activation caused by turbulence is not unsatisfactory if you recognize it and correct promptly.
What airspeed should you use for slow flight?
There is no single number. Fly just above the stall warning for your configuration; the Airplane Flying Handbook suggests 5 to 10 knots above the 1G stall speed as a good target. Find it by slowing to the warning, lowering the nose slightly to eliminate it, and adding power to hold altitude.
What are the ACS tolerances for slow flight?
Altitude within 100 feet, heading within 10 degrees, airspeed within +10/-0 knots and the specified bank within 10 degrees, with the maneuver completed no lower than 1,500 feet AGL in a single-engine airplane.
Why does slow flight take so much power?
Slow flight is on the back side of the power curve, below the speed for minimum drag. There, flying slower takes more power, not less, and in turns you need still more power to hold altitude.
How do you recover from slow flight?
Add power, then apply forward pressure to reduce the angle of attack and hold altitude as the airspeed increases. Stay coordinated, retract any flaps as the airspeed builds while anticipating the change in angle of attack, and retrim.