Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Private Pilot Theory > Ch 6 Weather > Flashcards

Ch 6 Weather Flashcards

You may prefer our related Brainscape-certified flashcards:
Charter Pilot (Part 135) - Oral flashcards
1
Q

Unstable air
- cloud, rain, turbulence, visibility

A

more vertical development, moist and warm

  • cumulus clouds
  • shower rains
  • rough turbulence
  • good visibility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Wake Turbulence
1. when departing after lg aircraft landed
2. landing behind lg aircraft
3. taking off behind lg aircraft
4. lg aircraft just taken off & you approach to land

A
  1. lift off beyond their touchdown
  2. land beyond their touchdown
  3. lift off before the lg aircraft rotation pt.
  4. touchdown before the lg aircraft’s liftoff point.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
  1. Rime ice
  2. Clear ice
  3. Mixed
A
  1. can be found in stratus clouds, instant icing, small drops -20C & -15C
  2. develops in an area of large supercooled water droplets, difficult to see, -10C & 0C
  3. occurs in temp. between -10C & -15C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Classification

A

Polar or tropical
- cool or warm

Continental or Maritime
- dry or moist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Clouds with vertical development

A
  1. cumulus= can indicate a shallow layer of instability, turbulence, little icing
  2. Towering Cumulus= indicate a fairly deep area of unstable air, moderate to heavy turbulence w/ icing. Often develop into thunderstorms
  3. Cumulonimbus (rainmaker)= large, vertically developed, in very unstable air. contain large amount of moisture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Temperature inversions

A

occur in stable air calm winds, near the sfc on cool, clear nights

sfc is cooler than the air above it and visibility is poor, restricted by fog / low clouds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q
  1. Gas to Liquid
  2. Liquid to Gas
A
  1. condensation
  2. evaporation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
  1. air mass thunderstorm
  2. severe thunderstorm
A
  1. short-lived, no strong winds
  2. wind gusts +50 kt, tornadoes, hail
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Mountain Breeze

A

night, downslope flow, 5 to 15 kt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Convective turbulence
aka ?

A

aka thermal turbulence
daytime over land in fair weather

rising heated air from the sfc

when air is moist, the currents may be marked by build-ups of cumulus clouds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Squall line

A

Mixture of storms in a continuous line

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Land Breeze

A

night, from the cooler land to the warmer water

Alt: 1,000 to 2,000 AGL
extend between 5 and 100 NM inland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

High Clouds

A

Alt: base above 20,000 agl
serius icing and turbulence

  1. cirrus= above 30,000, thin, patches or narrow bands. can warn approaching bad weather
  2. cirrostratus= thin, layer/ sheet, low moisture, no icing
  3. cirrocumulus= patchy, light turbulence
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

LLT (low-level turbulence)
4

A
  • Below 15,000 MSL
  • due to sfc heating or friction
    1. mechanical
    2. convective
    3. wake turbulence
    4. frontal turbulence
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Cold front
1. fast moving
2. slow moving

A
  1. sfc friction slows the mvmt
    leading edge bulge out & steepen front’s slope
  2. leading edge shallower
    - meets stable air = stratus form behind
    - unstable air = lg # of vertical clouds form
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The greatest instability occurs when

A

the air is both warm and moist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q
  1. Wind Shear
  2. Microburst
A
  1. drastic shift in wind speed and direction, wind shear turbulence is associated with all thunderstorms
  2. can last more than 15 min. and wind speed of 25 kt
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Convection

A

cool air= heavier, denser > sinks
warm air= lighter, less dense > rises

movement of air up and down

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Mountain Wave Turbulence

A

stable air moves across a ridge
wind is +40 kt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When you encounter turbulence when approach for landing

A
  1. fly a power-on approach at an airspeed slightly above the normal approach speed.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  1. fog
  2. ground fog
  3. radiation fog
A
  1. any low cloud within 50ft of ground
  2. less than 20ft deep
  3. flat sfc on clear, calm, humid nights. stable air associated w/ H pressure systm.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Atmospheric Pressure

A

The unequal heating of the sfc modifies air density, creates circulation patterns and causes changes in pressures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Atmospheric Composition

A

78% Nitrogen
21% Oxygen
1% other gases

A cubic foot of the atmosphere can contain from 0 to 4% of water vapor. Responsible for major changes in the weather.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What changes when crossing a front

A

temp.
pressure
wind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Source Region

A

Area where air mass gets the properties of temp. and moisture that determines its stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Precipitation induced fog

A

Warm rain falling though cold air, evaporation occurs and saturates the air causing fog. Fog doesn’t clear until the rain moves away.

27
Q
  1. Liquid to solid
  2. Solid to Liquid
A
  1. freezing
  2. melting
28
Q

Frictional force

A

Air moves from high pressure (clockwise) to low pressure (counterclockwise)

Within about 2,000ft AGL, Pressure gradient force if greater

At high altitudes, Coriolis Force is greater

29
Q

Dewpoint

A

temp. at which air reaches a state where it can’t hold more water

anticipate fog when dewpt./ temp. is 4F (2C) or less and decreasing

dewpt. is the temp. to which air must be cooled to become saturated

30
Q

Temperature inversions

A

occur in stable air calm winds, near the sfc on cool, clear nights

sfc is cooler than the air above it and visibility is poor, restricted by fog / low clouds

31
Q

Atmospheric Circulation

A

movement of air relative to the earth’s sfc

32
Q

pressure gradient:
1. trough - - -
2. col
3. ridge /\/\/\

A
  1. elongated area of low pressure
  2. neutral area between 2 highs or lows, or intersection of a ridge and a trough
  3. elongated area of high pressure
33
Q

Capping Stable layer

A

top of convective layer, where smooth air begins

34
Q

3 Cell Circulation Pattern

A

Polar Cell > 60 lat. to N
Ferrel Cell > 30 to 60 lat.
Hadley Cell > 0 to 30 lat.

35
Q

CAT

A

Clear air turbulence
above 15,000 or any altitude with no visual warning

36
Q

Stratosphere height

A

up to aprox. 160,000 ft

37
Q

Atmosphere exists within:

A

30 km (100,000 ft)

38
Q

Temperature inversions

A

occur in stable air calm winds, near the sfc on cool, clear nights

sfc is cooler than the air above it and visibility is poor, restricted by fog / low clouds

39
Q

Airmass

A

large body of air w/ fairly uniform temp. and moisture

40
Q

Sea Breeze

A

day, cool, dense air (H) moving inland from water

Alt:1,500 and 3,000 AGL
Speed: can reach 10 to 20 kt

41
Q
  1. solid to gas
  2. gas to solid
A
  1. sublimation
  2. deposition
42
Q

Relative humidity

A

actual amount of moisture in the air compared to the total amount that could be present at that temp.

43
Q

Troposphere alt

A

sfc to about 36,000

44
Q

Advection

A

lateral movement of temp./air

45
Q

Atmospheric stability

A

atmospheric resistance to vertical motion

46
Q
  1. LLWAS
  2. TDWR
  3. in-flight visual indicators
A
  1. low-level wind shear alert system
  2. terminal doppler weather radar
  3. ring of dust, virga, trees moving diff. directions
47
Q

Low clouds

A

Alt: sfc to 6,500 agl
can create icing hazard to aircraft

  1. status = flat, cover a wide area
  2. stratocumulus= layer of white puffy clouds
  3. nimbostratus= dark clouds, rain or snow
48
Q

Valley Breeze

A

day, upslope flow of air, 5 to 20 kt

49
Q

Life Cycle
1. Cumulus stage
2. Mature stage
3. Dissipating stage

A
  1. start of vertical mvmt., updraft
  2. rain (downdraft) fall.
  3. 15-30 min after mature stage, mostly downdraft
50
Q
  1. approaching a front toward the cool air
  2. approaching toward warm air
A
  1. pressure drops slowly until you cross, then rises quickly
  2. pressure drop abruptly, then rises slowly
51
Q

stable air
- clouds, rain, turbulence, visibility

A

resists convection, cool and dry

  • stratus clouds
  • steady/ cont. rain
  • little to none turbulence
  • poor visibility
52
Q

Virga

A

streaks of rain that evaporate before reaching the ground

53
Q

Frontal turbulence

A

Friction between the two opposing air masses

54
Q
  1. advection fog
  2. upslope fog
  3. steam fog
A
  1. hot, moist air moves over to cooler sfc. Common under cloudy skies coastlines. 15kt intensify fog. above 15 kt, turbulence and stratus clouds.
  2. moist, stable air moves up a mountain.
  3. cold, dry air moves over warm water. Can produce icing hazard and low-level turbulence bc it forms in unstable air
55
Q

Layer of the atmosphere

A
  1. troposphere
    • tropopause
  2. stratosphere
  3. mesosphere
  4. thermosphere
56
Q

Middle Clouds

A

Alt: 6,500 to 20,000 agl
moderate turbulence and potentially severe icing

  1. altostratus = flat & dense, cover wide area
  2. altocumulus= patchy, uniform clouds. when altostratus break up
57
Q

Mechanical Turbulence

A

when wind blows around hangars, trees, or perpendicular to steep hills or mountain ridges

58
Q

Conditions for thunderstorms to develop

A
  • lifting force
  • unstable air
  • high moisture
59
Q

What to do when you encounter turbulence

A
  1. slow the plane to maneuvering speed or less
  2. maintain a level flight altitude
  3. accept variations in airspeed and altitude
60
Q

Coriolis Force

A
  • Affects all objects moving freely across the face of the earth.
  • Airplane flight paths end up tracing a curved path due to the earth’s rotation.
  • The greater the speed of the object, the greater the deviation.
61
Q

Restrictions to visibility

A

-haze
-smoke
-smog
-volcanic ash
-dust

62
Q
  1. Coriolis Force Northern hemisphere
  2. Coriolis Force Southern hemisphere
A
  1. deviation to the right
  2. deviation to the left
63
Q

Tropopause

A

a level not a layer, acts as a lid to confine water vapor & weather

64
Q

pressure gradient:
1. closely spaced isobars
2. spread apart isobars

A
  1. strong winds and large pressure changes
  2. low winds and weak pressure gradient

Private Pilot Theory (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions