Cap 15 ICING

Question 1

What could effect icing?

Answer 1

Reduce aerodynamic performance
Restrict a/c controls
Reduce visibility
Increased stall speed
Instrumnet error blocked sensors

Question 2

What type of speed and shape of the wind profile makes the icing accumulation worst?

Answer 2

Higher speed will increase accumulation ,BUT SPEED ABOVE 0.4 MACH the compressibility of the air melts the ice.
Sharp profile accumulates more ice bc air has less time to spread when encountering the wing profile so ice will build up faster

Question 3

Types of ice on the airframe?

Answer 3

> clear ice (translucent),supercooled water-droplets
rime ice (opaque ice) small supercooled water droplets
mixed ice (combination of rime and clear ice)
hoar frost ,moist warm air cooles on a cold surface (sublimation)
Freezing rain , from a warm front falling through a cold mass which freezes

Question 4

Clear ice carathersitics?

Answer 4

Large supercooled water droplets at temp between 0/-15 degrees .
Part of ice will freeze instantly, the remaining will flow back and then freeze.
Solid glass lice ice ,which is hard and heavy and difficult to remove

Question 5

Rime ice caratterisctics?

Answer 5

Smaller scwd ,colder than -15c large amount of it freeze instantaneously and less flow back
Trap bubble of air resulting in a milk like appearance
Middle level cloud AS,AC, low level ST,SC,NS

Question 6

What is it a Cold soaked wing ?

Answer 6

The fuel in the wings cools the surface of the wing and the air surrounding will freeze

Question 7

Snow issues in air and ground?

Answer 7

Not a big issue in the air if not mixed with supercooled water droplets.
On the ground is an hazard

Question 8

ICE ACCUMULATION IN PISTON ENGINES (CARBURATOR)?

Answer 8

ICE CAN OCCUR IN TEMP BETWEEN 0/+15 DEGREES WITH HIGH HUMIDITY.(SERIOUS ICING)
AND ALSO FORM BETWEEN -10/+30 DEGREES WITH THE RIGHT AMOUNT OF HUMIDITY.

Question 9

HIGH CLOUD ICING CONDITIONS?

Answer 9

VERY LOW OF ICING

Question 10

MID LEVEL CLOUD ICING CONDITIONS?

Answer 10

LIGHT TO MODERATE OF ICING

DEPENDING ON FREEZING LEVEL ,CLEAR ICE POSSIBLE BETWEEN FZL TO +5000FT,ABOVE THAN RIME ICE

Question 11

LOW LEVEL ICING CONDITIONS

Answer 11

LIGHT TO MODERATE OF ICING

NORMALLY CLEAR ICE,BUT IF ITS COLD ENOUGH RIME ICE ALSO POSSIBLE

Question 12

CBs and NIMBOSTRATUS ICING CONDTIONS

Answer 12

MODERATE TO SEVERE ICING

MOST OF ICE WILL BE CLEAR ICE,AT HIGHER LEVELS RIME ICE

Question 13

SEVERITY OF ICING ?

Answer 13

SEVERE» The rate of accumulation is such that deicing/anti-icing equipment fails to reduce or control the hazard.
Immediate diversion is necessary

MODERATE» The rate of accumulation is such that even short encounters become potentially hazardous and use of
dicing/anti-icing equipment or diversion is necessary

LIGHT» The rate of accumulation may create a problem if flight is prolonged in this environment (over 1 hour). Occasional use of dicing/anti-icing equipment
removes/prevents accumulation. It does not present a problem if the dicing/anti-icing equipment is used

TRACE» Ice becomes perceptible. Rate of accumulation slightly greater than rate of
sublimation. It is not hazardous even though dicing/anti-icing equipment is not used unless encountered for an extended period of time (over 1 hour)

Question 14

AVG FZL HEIGHTS

Answer 14

JANUARY>>
~ 0ft average lattitude 50N,except near gulf streeam goes up to 70N roughly and near east asia 35N.
~10000ft near tropic of cancer
~16000ft equator
~10000ft near 40 S
~0ft 60 S

JULY>>
~8000ft average 60 N roughly
~16000ft around tropic of cancer
~18000ft at the tropic of cancer near middle east,est asia
~8000ft 40S
~0ft 60s