Slow flight

Slow flight: airspeed range from maximum endurance speed down to just above stalling speed for existing conditions (TP 1102).

Met in (TP 1102):

• Take-offs
• Landings
• Recovery from a misjudged landing
• Approach to a stall

Entry:

1. From straight-and-level at max endurance speed, raise nose past normal nose-up limit.
2. Airspeed and height fall.
3. Add power to hold altitude.

Once established, power controls altitude, not pitch:

• Gusty wind: raise airspeed above minimum to allow for gust factor.

Controls:

• Ailerons lose effectiveness first and most noticeably; lower speed, less effective.
• Elevator and rudder stay effective (propeller slipstream).
• Surfaces lose effectiveness as AoA rises, regain it as AoA falls; reducing AoA restores aileron roll control (AC 700-031 s.7.2(1)(h)).

Minimum controllable airspeed: nose pitches down with full power = airspeed below minimum controllable, aircraft stalled.

Near the stall: air density, weight, and flap or gear drag may make height impossible to hold, e.g. turn after take-off at high weight and critical density altitude (TP 1102).

After lift-off (low airspeed, low height):

• Abrupt pull-up or power cut can stall the aircraft.
• Set correct nose-up climb attitude. Too nose-high: unrecoverable stall, or too little climb to clear obstacles.
• Take extra care in a climbing turn made before a safe height (TP 1102 Ex.12).

Duration:

• Uneconomical: higher fuel use.
• Prolonged periods may overheat some engine components (TP 13723E Ex.11 note).
• Keep it short.

Do not use it to (TP 1102):

• Wait out weather
• Inspect a landing area
• Search for ground fixes when lost

Climb practice: dual includes slow flight in a climb to simulate an overshoot at high density altitude or past obstacles. Shows why to leave slow flight promptly.

Trap: holding altitude with pitch alone. In slow flight pitch is near its limit; power restores altitude.

Practice