Regional Gliding School u Occurs when the wing is no longer capable of producing sufficient lift to...

Regional Gliding School

Occurs when the wing is no longer capable of producing sufficient lift to counteract the weight of the aircraft. A smooth laminar airflow over the wing is needed to produce lift. The stall occurs when the angle of attack is increased to a point where the steady, streamlined flow of air is unable to follow the upper camber of the airfoil. The airflow separates from the wing, becomes turbulent, and loss of lift occurs. As the angle of attack increases, the centre of pressure moves forward on the wing until the CRITICAL ANGLE OF ATTACK is reached. At this point the C of P moves abruptly backwards on the wing which is now stalled.

STALLS


Weight: the greater the weight causes the aircraft to operate at a higher angle of attack. Therefore, it has a higher stalling speed.

C of G: the further forward the C of G moves, the higher the stalling speed. The further back it moves the lower the stalling speed.

Turbulence: Higher stalling speed because an upward vertical gust could cause the aircraft to exceed its critical angle of attack.

Factors Affecting the Stall


Turns: As the amount of bank in a turn increases the stalling speed increases because the load factor increases.

Flaps: By increasing the lifting potential of the wing it reduces the stalling speed.

Aircraft Condtion: Snow, Frost, Ice, Dents can all increase the stalling speed because of increased drag.



An aircraft will stall if the critical angle of attack is exceeded.

It will stall at any airspeed if the critical angle of attack is exceeded.

It will stall at any attitude if the critical angle of attack is exceeded.

It will stall at the same indicated airspeed regardless of altitude.

STALLS


NOTE: You must use the buttons in the Confirmation Stage


A

B

C

D

Weight

Turbulence

All the above

Let's try a few review questions on Theory of Flight:

Question #1 - What factors affect the stall?

C of G

Theory of FlightTheory of FlightStalls, Spins, Spiral Dive & Load FactorStalls, Spins, Spiral Dive & Load Factor

I’m afraid that answer is incorrect

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Flying Scholarship Program


That answer is correct.

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Weight: the greater the weight causes the aircraftto operate at higher angle of attack , therefore ahigher stalling speed

C of G: the further forward the C of G moves thehigher the stalling speed becomes. the further backit moves the lower the stalling speed.

Turbulence: Higher stalling speed because anupward vertical gust could cause the aircraft toexceed its critical angle of attack.



A

B

C

D

Yes

No

Both A and C


Question #2 - Will the aircraft always stall at the same angle of attack?

Only at the same altitude



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Let's move on...


An aircraft will stall if the critical angle of attack is exceeded.

It will stall at any airspeed if the critical angle of attack is exceeded.

It will stall at any attitude if the critical angle of attack is exceeded.

It will stall at the same indicated airspeed regardless of altitude.

STALLS


Spinning may be defined as auto-rotation which develops after an aggravated stall. If a disturbance causes a stalled airplane to drop one wing, or if rudder is applied to produce a yaw, the downgoing wing will have a greater angle of attack to the relative airflow will receive less lift and will tend to drop more rapidly. Drag on the downgoing wing increases sharply increasing the angle of attack of the downgoing wing still further and stalling it further. The nose drops and auto-rotation sets in.

SPINNING


A Spiral Dive is a steep descending turn in which the airplane is in an excessively nose down attitude. Excessive angle of bank, rapidly increasing airspeed and rapidly increasing rate of descent characterize it. Structural damage can occur to the airplane if the airspeed is allowed to increase beyond its limits.

SPIRAL DIVE


A spiral dive resembles a spin but don’t confuse the two. In a spin, the airspeed is constant and low, it is a stalled condition. In a spiral dive, the airspeed increases rapidly, it is not a stalled condition.

SPIRAL DIVE


Dead Load:• the weight of the aircraft standing on the ground.

Live Load:• the change in dead load due to acceleration or turns.

Load Factor: • the ratio of the actual load acting on the wings to the

gross weight of the aircraft. In other words it is the live load divided by the dead load.

LOAD FACTOR


Why load factors are important– Dangerous overload is possible.– An increase in the load factor will result in an

increase in the stalling speed.

LOAD FACTOR


Load factors are expressed in G's– When on the ground or in straight and level

flight, you are said to be under the force of 1G or one time the force of gravity.

– As the angle of bank increases so does the loading factor.

– In a banked attitude of 60 = 2G's

LOAD FACTOR


NOTE: You must use the buttons in the Confirmation Stage


A

B False


Question #3 - In a spiral dive, the airspeed is constant and low, it is a stalled condition. In a spin, the airspeed increases rapidly, it is not a stalled condition.

True



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A spiral dive resembles a spin but don’tconfuse the two. In a spin, the airspeed isconstant and low, it is a stalled condition. Ina spiral dive, the airspeed increases rapidly,it is not a stalled condition.

SPIRAL DIVE


A

B

C

D

1G

1.6G

3G


Question #4 - How many G’s will you have in a 60 banked turn?

2G



Let's try again...




Let's move on...


Load factors are expressed in G's– When on the ground or in straight and level

flight, you are said to be under the force of 1Gor one time the force of gravity.

– As the angle of bank increases so does theloading factor.

– In a banked attitude of 60 = 2G's

LOAD FACTOR


Congratulations!!

You have now completed the Stalls, Spins, Spiral Dives & Load Factor lesson of the Theory of Flight Module. Of course, this lesson is always available to you for future reference if required.

You are now ready to move along to the next Theory of Flight lesson you have not completed or to any other module you wish. You can advance to the Self Test Module if you feel ready to challenge the final exam.

Good Luck!


Regional Gliding School u Occurs when the wing is no longer capable of producing sufficient lift to...

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