Helicopter Icing

Question 1

Flying a helicopter in rain a few feet below the freezing level(can, cannot) result in ice forming on the rotor blades because the area of (reduced, increased)pressure above the blades is associated with (higher, lower)
Temperatures than the environment temperature.

Answer 1

Can
Reduced
Lower

Question 2

When the environment temperature is between 0 c and -15 c and cloud droplets are large, —— ice is likely to form and when temperatures are much colder and/or droplets area small, ——- ice will form.

Answer 2

Clear
Rime

Question 3

A (major, minor) risk of rotor blade icing is the resulting unbalancing of blades which can cause (recirculating, ground resonance) problems on landing.

Answer 3

Major
Ground resonance

Question 4

The initial build up of ice initially occurs in the (tip, middle) region of blades and since this is the blades (driving, driven) region during an engine off descent, it follows that a safe autorotation (may, may not) be possible.

Answer 4

Middle
Driving
May not

Question 5

Above approximately -6 deg the tip regions of blades are generally ( covered by, clear of) ice because of ——- heating resulting from high local speeds

Answer 5

Clear of
Kinetic

Question 6

Generally, ice accretion is (quicker, slower) on sharp objects and (quicker, slower) on blunt objects.

Answer 6

Quicker
Slower

Question 7

Flying in sleet (is, is not) unsafe because visibility through the windshield (will, will not) reduce when ——- forms.

Answer 7

Is
Will
Ice