Q1. Aircraft surfaces must be designed to suffer in flight aerodynamic degradation due to the ice formation
A. Yes, always.
B. Yes, but not during take off.
C. No, never.
D. Yes, but not during landing.
Q2. Which of the following are windscreen rain removal systems?
Curved and rear-sloping windscreen
Windshield wipers
Rain repellent: for torrential rain conditions
All of the above are correct
Which of the following are types of ice?
Clear ice
Rain ice
Rime ice
A safe flight must take also into account possible weather hazards that might be encountered. These can be of different types:
structural (gust, hail impact)
ice
lightnings
Mixed ice…
Is the Combination of glaze and rime ice
Can not occur today
Take place in clouds with temperature transition from small to large supercooled water droplets.
Options A and C are true
About Rime ice…
It is a Transparent air free sheet
We can see in flight in dense clouds of small supercooled water droplets
It has an opaque white structure due to air trapped between droplets
It has an opaque white structure due to the viscosity of the types of droplets
Effects of ice accretion on an aircraft
Weight increases
Alteration of airfoil shape
Loss of control due to freeze in the joints between control surfaces and wings / tailplanes
About frost/Hoar frost…
Ice crystals from sublimation when water vapour freezes
Ice crystals from condensation when water vapour freezes
Black crystaline structure
It does form a heavy blanket but roughens the surface --> increase aerodynamic performances