Retreating Blade Stall

Question 1

When airspeed increases and the reverse flow area on the ( advancing, retreating)side of the disc expands, the area of the blade not affected must operate at a ( greater, smaller) angle of attack.
It achieves this through (increased, decreased) flapping ( down, up).

Answer 1

Retreateing
Greater
Increased
Down

Question 2

When retreating blade stall begins, the sections of the retreating blade near the (root, tip) exceed their C lift max.

Answer 2

Tip

Question 3

The symptoms of retreating blade stall in most helicopters are rotor——- and——- felt through the aircraft. As the stall develops, the helicopter pitches (up, down) and (rolls, yaws).

Answer 3

Vibration
Roughness
Up
Rolls

Question 4

Using back cyclic to recover from retreating blade stall (is, is not) recommended because the flare effect (reduces, increases) angle of attack.

Answer 4

Is not
Increases

Question 5

Using forward cyclic when experiencing retreating blade stall (increases, decreases)angles of attack on the advancing side and (increases, decreases) angles of attack on the retreating side which results in the stalled conditions of retreating blade becoming (worse, better)

Answer 5

Decrease
Increase
Worse

Question 6

Conditions likely to lead to retreating blade sail include (high, low) airspeed, manoeuvres involving (high, low) load factors and flight in —— conditions.

Answer 6

High
High
Turbulent

Question 7

The reason why V ne ( ‘never exceed speed ‘) (increases, decreases) with altitude is that retreating blade stall is experienced at (high, lower) airspeeds because angles for attack for flight at increased altitude are generally (high, low)

Answer 7

Decreases
Lower
High

Question 8

Flight at greater gross weight incurs a (higher, lower) Vne ( ‘never exceed’)

Answer 8

Lower