Meteorology Part 3

Question 1

Icing defined

Answer 1

If the skin of the aircraft is below 0 degrees, ice will form.

Question 2

Clear Ice
Rime Ice
Mixed Ice

Answer 2

Clear = slowly freeze after impact aircraft = covers more of the wing & smooth
Rime = immediate freeze, traps air, white & rough
Mixed = both

Question 3

clear ice is usually from what cloud

Answer 3

cumuliform

Question 4

Rime ice usually is formed from what cloud?

Answer 4

stratiform

Question 5

Results of icing:

Answer 5

increase drag (300-500%)
increases weight
increase stall speed
decreases lift
decreases thrust
blocks vision
plugs pitot tube & static ports

Question 6

catching rate

Answer 6

thin wing
large water droplets
high speed

Question 7

icing conditions

Answer 7

0 to -25 = severe clear icing
-25 to -40 light to mod rime/mixed
below -40 = little chance of icing

Question 8

if you notice ice…

Answer 8

turn around!
get to lower/warmer air
contact FSS for freezing level update
fast decisions!

Question 9

air masses define

Answer 9

large sections of the troposphere with uniform properties
(can be thousands of miles)

Question 10

Most common air masses in Canada (4 cold to warm)

Answer 10

1) Continental Arctic -dry, very cold, stable
2) Maritime Arctic -moist unstable in lower levels
3) Maritime Polar - moist, cool, unstable
4) Maritime Tropical - moist, hot, very unstable

Question 11

3 factors that determine an air mass:

Answer 11

1) moisture
2) temperature
3) stability of air

Question 12

cold air masses typically are:

Answer 12

instability
turbulence
good visibility
cumuliform cloud
percipitation: showers, hail, thunderstorms

Question 13

warm air masses

Answer 13

stability
smooth air
poor visibility
stratiform cloud
precipitation: drizzle

Question 14

fronts =

Answer 14

the boundary between 2 air masses
–typically air masses do not readily mix

Question 15

frontal slope

Answer 15

the distance from the leading surface of the front to where it meets the ground.
Ratio
cold front ratio = 1/50 to 1/100miles
warm front ratio = 1/150 to 1/200miles

Question 16

overrunning frontal slope

Answer 16

a faster moving warm front will overrun & lift over a cold air mass

Question 17

undercutting frontal slope

Answer 17

faster moving cold mass will undercut the warm air and lift it up

Question 18

cold fronts result =

Answer 18

fast cold air comes in and lifts warm air = warm air lifts, expands, cools and then condenses to form clouds & precipitation

Question 19

warm front results

Answer 19

fast warm air overruns cold = warm lift is liften, expands, cools, condenses, and forms clouds/precipiation

Question 20

There are front symbols (you need to know these)
1) warm front
2) cold front
3) stationary front
4) occluded front

Answer 20

1) red half circles
2) blue triangles
3) alternating red half circles & blur triangles
4) purple half circle/triangle alternating

Question 21

frontogenesis & frontolysis

Answer 21

frontogenesis = front being created
frontolysis = front dissipates

Question 22

Upper fronts

Answer 22

A non-occluded situation where an air mass is sitting on top of another air mass.
Ex: Rockey mnt. very cold air is trapped at the surface = warm front will ride over the colder air below.

Question 23

Frontal depression

Answer 23

Disturbance created due to the instability of frontal situation (temp diff between air masses)

Question 24

Occlusion or occluded front
aka: trowal

Answer 24

warm air is sandwiched between cold and cool air. Faster moving cold air will catch up with itself & undercut the warm air between the cooler air in front. = lift up this air & create an occlusion

Question 25

Weather at a front depends on:
1) speed of front
2) moisture
3) stability of air being lifted

Answer 25

1) faster = more abrupt vertical motion = squall lines & severe weather can result.
2) Moisture = clouds = precipitation to form.
3) causes diff cloud types. more showery & turbulent.

Question 26

3 things required to form a thunderstorm

Answer 26

1) Large instability
2) Lifting agent
3) High moisture content
–produced by cumulus clouds

Question 27

Life-cycle of a thunderstorm

Answer 27

1) Cumulus Stage
–grows to become a towering cumulus cloud.
2) Mature Stage
–precipitation. Strong winds carry clouds ahead of storm = forms anvil shape.
3) Dissipating Stage
-~30mins after cells start to form. mainly downdrafts. least hazardous.

Question 28

Clear air turbulence (CAT)

Answer 28

–higher altitudes
–rhythmic & more annoying than harmful
–usually associated with wind shear

Question 29

SIGMETs Verse AIRMETs

Answer 29

both = info on hazardous weather conditions
SIGMET = more severe. aka: thunderstorms, dust storms, etc.
AIRMET = less severe. aka: turbulence, visibility, and icing

Question 30

ATC is required to advice their pilots whenever a SIGMET is issued within 150 nm of their airspace.

Answer 30

just fyi if they are busy they might not give you details. you are responsible for that info from FSS

Question 31

virga definition

Answer 31

precipitation that does not make it to the ground.
* avoid *

Question 32

microburst define

Answer 32

a downdraft (sinking air) in a thunderstorm that is less than 2.5 miles in scale

Question 33

ADF what is it & what can it help with?

Answer 33

Automatic direction finding (older planes often)
can help find lightning. Strikefinder or weather radar would be better tho.