Stall Speeds and Bank Angle

Stall speed is not one number — it is a small grid, and bank angle moves it further than most students expect. The published table is flown at one weight and one centre-of-gravity position, so read the conditions before you read the speeds.

At a glance

• Conditions for the whole tablelanding gear DOWN, throttle levers IDLE, C.G. at its most forward position (16.5%), weight 1230 kg (2712 lb), out of ground effect
• Flaps UP (KIAS / KCAS)0° bank 66 / 65; 15° 67 / 66; 30° 71 / 70; 45° 79 / 78; 60° 95 / 93
• Flaps T/O (KIAS / KCAS)0° bank 59 / 57; 15° 58 / 58; 30° 61 / 61; 45° 68 / 68; 60° 83 / 81
• Flaps LND (KIAS / KCAS)0° bank 54 / 55; 15° 55 / 56; 30° 59 / 59; 45° 65 / 65; 60° 79 / 78
• Altitude loss in a conventional stall recovery, banking below 30°about 250 ft, as shown in flight testing

The conditions the table was flown at

Every speed in the table applies with the landing gear DOWN and the throttle levers at IDLE, at a weight of 1230 kg (2712 lb), with the centre of gravity at its most forward position of 16.5%, and out of ground effect. Change any of those and the printed number no longer describes your aeroplane.

Reading across the bank angles

Each flap setting is tabulated at five bank angles from wings level to 60°. In every configuration the wings-level figure is the lowest of the practical numbers and the 60° figure is far higher — the flaps-UP row runs from 66 KIAS at 0° to 95 KIAS at 60°, a jump of 29 knots across the row.

The three rows are worth memorising as a set rather than one at a time: at any given bank angle, flaps LND gives the lowest stall speed and flaps UP the highest.

One printed inconsistency

In the flaps T/O row the 15° bank figure is printed as 58 KIAS, which is lower than the 59 KIAS printed at 0° bank, while the calibrated figures rise from 57 to 58 KCAS across the same pair. Every other flap setting rises from 0° to 15°. Learn the flaps T/O row as printed and do not build a rule on that one pair; the 30°, 45° and 60° figures in the same row are unaffected.

NOTE — Flight testing showed that recovering conventionally from a stall costs about 250 ft of altitude when the bank angle is under 30°.

Check yourself

• At what weight, C.G. position and gear position was the stall table flown?

• What is the flaps-UP stall speed in KIAS at 0° bank, and at 60° bank?

• Which flap setting gives the lowest stall speed at any given bank angle?

• How much altitude loss should you expect in a conventional stall recovery with less than 30° of bank?

• Which single pair of values in the table does not follow the pattern, and in which row?

Study aid — always fly your aircraft's current AFM/POH.