IF Unusual attitudes
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Instrument Flying
Unusual Attitudes
Unusual attitude: Causes
- Unusual attitudes can result from a number of conditions such as:
- Turbulence.
- Disorientation.
- Cockpit duties.
- Incorrect scan techniques.
- Incorrect trim.
- Errors in instruments interpretation.
- Instrument malfunction.
Unusual attitude: Symptoms
- Nose up attitude:
- Altimeter: increasing until stall and then decreasing.
- Vertical speed indicator: increasing until stall and then decreasing.
- Airspeed indicator: decreasing.
- Nose Down attitude:
- Alitmeter: decreasing.
- Vertical speed indicator: decreasing.
- Airspeed indicator: increasing.
- Spin:
- Airspeed indicator: decreasing.
- Altimeter: decreasing.
- Vertical speed indicator: decreasing.
- Turn-coordinator is deflected in direction of turn.
Recovery
- Recovery should be made by reference to the:
- Airspeed indicator.
- Turn coordinator.
- Altimeter.
- Vertical speed indicator.
- In moderate unusual attitude it may be possible to establish level flight using the attitude indicator.
- However in extreme attitude the information shown on the attitude indicator may become unreliable as a reference recovery.
- Attitude Indicator is accurate until it tumbles.
- Attitude indicator will tumble if maximum bank or pitch angle is exceeded:
- ~100-110° Bank.
- ~60-70° Pitch.
Nose up recovery:
- Check flight Intrument.
- Airspeed indicator, if airspeed decrease we are nose up.
- Turn coordinator for wing level.
- Altimeter and vertical speed indicator to know how much the altitude increases.
- Increase power to prevent further loss of airspeed.
- Simultaneously apply forward elevator pressure to lower the nose to prevent stall.
- Level the wing by applying coordinated aileron and rudder pressure to centre the turn needle and ball.
- When the airspeed stops decreasing, you are at or near level flight, stop forward elevator pressure.
Nose down recovery:
- Check flight Intrument.
- Airspeed indicator, if airspeed increase we are nose down.
- Turn coordinator for wing level.
- Altimeter and vertical speed indicator to know how much the altitude decreases.
- Reduce power to idle to prevent excessive airspeed and loss of altitude.
- Level the wing by applying coordinated aileron and rudder pressures to centre the turn needle and ball.
- Apply smooth back elevator pressure: to return to level flight.
- When the airspeed stop increasing, stop the back elevator pressure and climb or level off.
Spin recovery:
- The spin is the most critical unusual attitude of all because of the disorientation that usually accompanies it.
- The first requirement for spin recovery is to determine the direction in which the aircraft is spinning.
- The turn needle of the turn coordinator is the only reliable instrument for this purpose (the ball it’s not accuracy).
- The turn needle of the turn coordinator will show a deflection in the direction of the spin.
- The altimeter will show a rapid loss height.
- To differentiate between a spin and a spiral, check the airspeed.
- Airspeed will be low (near the stalling speed) in a spin.
- Airspeed will be high and increasing in a spiral.
- The recovery procedure:
- Power idle
- Neutralize ailerons (ailerons neutral)
- Apply and hold full rudder opposite to the direction of rotation (if the turn needle is full right apply full left rudder).
- Move the control column forward to break the stall (full down elevator might be required in some airplanes).
- Hold these control inputs until the turn needle starts moving back to the centre, indicating that the spin has stopped.
- Neutralize rudder (needle at or near the centre).
- Apply back pressure on the control column to ease the aircraft out of the dive.
- When the airspeed begins to decrease, hold the pitch attitude constant and apply power to resume cruising flight.
- Keep the turn needle and ball centered with the coordinated control pressures.
Review questions
- What is the order of control for a nose-high attitude?
- Which instrument will indirectly tell you the pitch of the aircraft?
- If we are disoriented what should we do?
- During the spin recovery after you apply full opposite rudder how can you confirm the rotation has stopped?