1. Basic Stalling The Flight Training Manual - Section 10
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2. Objectives To control the aeroplane to the point of stall,
recognise the symptoms of the approaching stall,
experience the stall itself, and
recover with minimum altitude loss.
recognise the symptoms of the approaching stall, and
recover at stall onset with minimum altitude loss.

3. Why Learn Stalling?
To avoid the inadvertent stall – learn to recognise the symptoms of the approaching stall and apply the correct recovery technique
To become familiar with the stall as there are times when an aeroplane is operated close to the stall speed.
Every flight (should) end with a controlled approach to the stall during the approach and landing.

4. Principles of Flight Basic Stall Configuration Lift Formula
Airflow Over the Wing
Coefficients of Lift and Drag
At the Stall

5. Basic Stall Configuration
When an aeroplane stalls the engine doesn’t stop
A wing stalls when the critical angle of attack (≈15) is exceeded and the airflow breaks away.
The speed at which this occurs is dependent on the aircraft configuration and the manoeuvres being carried out.
Power
Idle
Flap Up

6. Lift Formula L = CL ½ ρV2S L  AOA x IAS
While Straight and Level: Weight is constant
To maintain Straight and Level: Weight = Lift
With Power at Idle the IAS reduces
To maintain Altitude, the AOA of must
INCREASE

7. Laminar airflow over the wing
RAF
Centre of Pressure

8. Airflow starts to break away Centre of Pressure moves forward
Airflow Over the Wing
Airflow starts to break away
Centre of Pressure moves forward

9. Airflow Over the Wing
Critical Angle reached, airflow breaks away from the wing
Lift decrease, Large Increase in Drag
Centre of Pressure moves Rapidly Aft

10. Coefficients of Lift and Drag

11. At the Stall Decrease in Lift Large Increase in Drag
Centre of Pressure moves Rapidly Rearwards
Stall Speed (VS1)
C152 – 38kt
PA38 – 52kt
Aeroplane:
Sinks, and
Pitches Nose Down

12. Airmanship A Training Exercise Don’t carry passengers
Situational Awareness
Aircraft Position – training area & other traffic
Aircraft Configuration and the Phase of Flight
Recognise the Stall Symptoms
HASELL & HELL Checks

13. HASELL (Pre-manoeuvre checks)
Height
Airframe
Security
Engine
Locality
Lookout
Sufficient to recover by a safe height
Configured for the entry (Flaps up)
No loose articles, harnesses secure.
Check during pre-flight
Temperatures and Pressures normal
Mixture RICH
Fuel Sufficient, Fullest Tank
Pump ON (Pressure)
Clear of Populated Areas, Traffic, Airfields, Cloud
One 180° or Two 90° turns

14. HELL (between manoeuvres)
Height
Engine
Locality
Lookout
Regained and sufficient to recover by a safe height
Temperatures and Pressures normal
Clear of Populated Areas, Traffic, Airfields, Cloud
One 90° turn
If carried out in one direction, the exercise is carried out in a box

15. Pre-flight Temperatures and Pressures Throttle Carb Heat
Aeroplane Management
Pre-flight
Temperatures and Pressures
Throttle
Carb Heat
No loose objects
After a climb to altitude, allow time to stabilise
Smooth but positive movements
Full On if Carb Ice suspected and when reducing power below green arc (2100 RPM)
Off when applying Full Power – just before the stall or immediately after applying full power.

16. Human Factors
An awareness exercise in which more exposure and practice will result in a better recovery technique.
Practice regularly, even after obtaining your licence.
Regular turns and higher than normal nose attitude may lead to disorientation.
Allow time between stalls to regain orientation.
Stress will reduce with overlearning the procedure.
If feeling uncomfortable – speak up.

17. Air Exercise – Entry HASELL Reference Point Carb Heat Throttle
Keep Straight
Maintain Altitude
IAS 55kt
Stall Warning
Checks Completed
To Keep Straight On
FULL ON/HOT
Idle
Rudder
Increasing Back Pressure
Carb Heat OFF/COLD

18. Air Exercise – Symptoms
Speed Low and Decreasing
Controls Less Responsive
Attitude Nose High
Buffet
SCAB

19. Air Exercise – At the Stall
The Aircraft will
Pitch Nose Down
Sink
Possibly Drop a Wing

20. Recovery – To Unstall the Wings
How?
Reduce the Angle of Attack below the Critical Angle
Check CENTRALLY Forward with the Control Column
Do Not Use Ailerons
How Much?
The position for Best Lift/Drag Ratio
Do not push forward to dive at the ground
The aeroplane will descend
Recover to Straight and Level with: P A T
Power
Attitude
Trim
Full
Straight and Level
Hands Off
Altitude loss will be about 300 feet

21. Recovery – To Minimise Altitude Loss
Power + Attitude = Performance
Unstall the Wing
Power
Raise the Nose
Accelerate
Reduce AOA to Best L/D Ratio
Full Power – Balance with Rudder
To the Horizon (to stop the sink)
To VY (Best ROC)
C152 – 67kt / PA38 – 70 kt
Climb to Reference Altitude at VY
Regain Straight and Level
Maximum Altitude Loss 100 feet
Stick Power Rudder

22. Recovery at the Onset/Incipient Stage
Recovery at the Onset or Incipient Stage:
At the Stall Warning or Buffet
Stick Power Rudder
Stall Prevented and ideally the altitude loss 0 feet

23. Recovery Summary
< 50ft
100 ft
300 ft