Turning

Forces in the Turn

An aircraft turns by banking. When the wings are tilted, the total lift vector is tilted as well. The horizontal component of lift acts as the centripetal force that pulls the aircraft toward the center of the turn.

In a banked turn, lift can be resolved into two components:

• Vertical component — supports the weight of the aircraft (acts upward, opposing gravity).
• Horizontal component — acts toward the center of the turn, providing the centripetal force needed to curve the flight path.

The steeper the bank angle, the greater the horizontal component — and the tighter the turn for a given airspeed.

Use of Controls

Ailerons — Rolling Into the Turn

Ailerons are the primary control for establishing and adjusting bank angle. Deflecting the control wheel (or stick) in the direction of the desired turn raises one aileron and lowers the other, creating a difference in lift between the wings that rolls the aircraft.

Adverse Yaw

When ailerons are deflected, the wing going up (with the lowered aileron) produces more lift — and therefore more induced drag — than the wing going down. This differential drag causes the nose to yaw away from the direction of the turn. This effect is called adverse yaw.

Once Established

After the desired bank angle is established, very little rudder is needed to maintain coordination. The ailerons are neutralized (or nearly so) to hold the bank constant.

Overbanking Tendency

In an established turn, the outer wing travels faster than the inner wing (it has a larger radius). Because it moves faster, it generates more lift — creating a tendency to overbank. You will need a small amount of aileron pressure away from the turn to prevent the bank from increasing beyond 30°.

Increased Lift Requirement

Because only the vertical component of lift supports the aircraft's weight in a turn, the total lift must be increased to maintain altitude. This is achieved by applying back pressure on the control column, which increases the angle of attack.

Effect on Stall Speed

The increased angle of attack in a turn has several consequences:

• More induced drag — the aircraft tends to slow down (approximately 5 knots at 30° bank if power is unchanged).
• Higher stall speed — at 30° bank, stall speed increases by approximately 7% compared to straight and level flight.
• Reduced stall margin — the gap between your flying speed and the stall speed narrows.

Climbing Turns

When combining a climb with a turn:

• Establish the climb first, then roll into the turn.
• Limit bank angle to a maximum of 15° — the reduced airspeed in a climb means less margin above stall.
• The outer wing (traveling faster) has a greater angle of attack, which increases the overbanking tendency. You need to actively "hold off" bank with opposite aileron.
• Rate of climb is reduced during turning — the vertical component of lift is less while banked, and some energy goes into turning.

Descending Turns

When combining a descent with a turn:

• Establish the descent first, then roll into the turn.
• Bank angle may be up to 30° — the higher airspeed in a descent provides greater stall margin.
• In a descending turn, the inner wing has a higher angle of attack. This creates a tendency for the aircraft to roll out of the turn (opposite to the overbanking tendency in level turns).
• You need to "hold on" bank — maintain aileron pressure into the turn to keep the bank constant.

Effect of Offset Seating

In side-by-side seating aircraft, the pilot's eye position is offset from the aircraft centerline. This creates a visual illusion during turns:

• In a left turn, the nose appears to be pitched higher than it actually is.
• In a right turn, the nose appears to be pitched lower than it actually is.

Be aware of this illusion and cross-check your instruments (altimeter, VSI) to confirm you are maintaining level flight during turns.

Turning onto Headings — Heading Indicator

The heading indicator (HI) is the primary reference for turning onto a specific heading. Because it takes time to roll the wings level, you must anticipate the rollout.

For example, if turning left from 360° to a heading of 270°, begin rolling wings level as the heading indicator passes through 285° (270° + 15°).

Turning onto Headings — Magnetic Compass

The magnetic compass suffers from turning errors caused by the dip of the Earth's magnetic field. In the Northern Hemisphere, the compass lags behind in northerly turns and leads ahead in southerly turns.

On easterly and westerly headings, compass turning errors are minimal. The 30° figure is approximate and applies at mid-latitudes — your instructor will discuss local variations.