Brainscape's Knowledge GenomeTM

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


See full index

IFR Refresher > Weather > Flashcards

Weather Flashcards

1
Q

What are the basic VFR weather minimums?

A

Class A - IFR only
Class B - 3SM/Clear of clouds
Class C - 3.152 (3SM/1,000’ above/500’ below/2,000’ horizontal)
Class D - 3.152 (3SM/1,000’ above/500’ below/2,000’ horizontal)
Class E -
- Above 10,000’ MSL = 5.111 (5SM/1,000’ above/1,000’ below/1SM horizontal)
- Below 10,000’ MSL = 3.152 (3SM/1,000’ above/500’ below/2,000’ horizontal)
Class G -
- Above 1,200’ AGL AND above 10,000’ MSL = 5.111 (5SM/1,000’ above/1,000’ below/1SM horizontal)
- Above 1,200’ AGL AND below 10,000’ MSL:
- Day = 1.152 (1SM/1,000’ above/500’ below/2,000’ horizontal)
- Night = 3.152 (3SM/1,000’ above/500’ below/2,000’ horizontal)
- Below 1,200’ AGL:
- Day = 1SM/Clear of clouds
- Night = 3.152 (3SM/1,000’ above/500’ below/2,000’ horizontal)

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

Where can en route weather information be obtained?

A

En route Flight Advisory Service (EFAS) - 122.0MHz between 5,000’ and 17,500’ MSL
Hazardous Inflight Weather Advisory Service (HIWAS) - Over select VOR stations marked on charts. Contains a summary of any AIRMET, SIGMET, convective SIGMET, Center Weather Advisories (CWA) and urgent PIREPs
DATALINK - Obtained through ground stations or satellites. Be aware of coverage gaps and information age
Automatic Terminal Information Service (ATIS)
Automated Surface Observation System (ASOS)
Automated Weather Observation System (AWOS)
ATC - Center weather advisories (CWA), Severe weather forecast alerts (AWW), SIGMETs and convective SIGMETs are broadcast to alert pilots of existing or anticipated adverse weather conditions
Onboard weather radar
Onboard lightning detector
Transcribed Weather Broadcast (TWEB) - Alaska only

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

What types of weather is in a SIGMET (WST)?

A

Advises of non-convective weather potentially hazardous to all types of aircraft issued when the following is expected to occur:

  • Severe icing not associated with thunderstorms
  • Severe/extreme turbulence or clear air turbulence not associated with thunderstorms
  • Dust storms or sandstorms lowering surface visibility below 3SM
  • Volcanic ash

NOTE:
-SIGMETs have a maximum forecast period of 4 hours

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

What types of weather is in a Convective SIGMET (WS)?

A

Advises of convective weather hazardous to all types of aircraft issued when the following is expected to occur:

  • “Severe” or greater turbulence
  • “Severe” or greater icing
  • “Severe” or greater low level wind shear
  • Tornadoes
  • Thunderstorms:
    • Severe thunderstorms due to:
      • Surface winds of at least 50 knots
      • Hail at the surface greater than 3/4 inches
    • Embedded thunderstorms
    • A line of thunderstorms at least 60 miles long affecting 40% of its length
    • Thunderstorms producing “heavy” or greater precipitation affecting more than 40% of an area of at least 3,000 square miles

NOTE:
-Convective SIGMETs are valid for 2 hours

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

What types of weather is in an AIRMET (WA)?

A

Alerts to weather of lower intensity than that which requires a SIGMET, which can affect all aircraft but are particularly hazardous to aircraft with limited capability:

  • AIRMET (S)
    • IFR conditions
    • Significant mountain obscuration
  • AIRMET (T)
    • Moderate turbulence
    • Sustained surface winds greater than 30 knots
    • Non-convective low level wind shear
  • AIRMET (Z)
    • Moderate icing
    • Can provide freezing level heights

NOTE:
-AIRMETs are valid for 6 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a “UA” or “UUA” report?

A

“UA” - PIREP (Pilot report)

“UUA” - Urgent PIREP (Urgent pilot report)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe a METAR:

A

METAR or Aviation Routine Weather describe surface weather observations in a standard international format which is published every hour

METAR (SPECI), or SPECial Issue, are issued when there is a significant change to in one or more reported element since the last scheduled METAR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe a TAF:

A

TAF or Terminal Aerodrome Forecast reports the forecasted weather around the station within a 55NM radius. It is issued every 6 hours and each forecast covers a 24 or 30 hour forecast period.

TAF (AMD), or Terminal Aerodrome Forecast AMenDments supersede the previous TAF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe an Aviation Area Forecast (FA):

A

An Aviation Area Forecast is a forecast of weather conditions in an area encompassing in several states, usually issued 3 times a day.

Aviation Area Forecasts in conjunction with SIGMETs and AIRMETs are typically used when a TAF is not available.

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

Describe a Surface Analysis Chart:

A

Surface Analysis Charts are generated from surface station observations and display pressure systems, isobars, fronts, airmass boundaries (such as drylines, outflow boundaries, etc.) and station information (such as wind, temp/dew point, sky coverage, precipitation, etc.).

Surface Analysis Charts are issued every 3 hours

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

Describe a Weather Depiction Chart:

A

Weather Depiction Charts are generated from surface station observations and depicts:

  • VFR (3,000’+ ceilings and visibility of 5+ SM)
  • Marginal VFR (1,000’ - 3,000’ ceilings and/or visibility of 3 - 5 SM, displayed as contoured areas)
  • IFR (less than 1,000’ ceilings and/or 3 SM visibility, displayed as shaded areas)
  • Basic METAR information at select stations (visibility, sky coverage, ceilings and obstructions to visibility)

Weather Depiction Charts are issued every 3 hours starting at 01:00 Zulu time

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

Describe a Radar Summary Chart (SD):

A

Radar Summary Charts (SD) depict precipitation type, intensity, coverage, movement, echoes and maximum cloud tops.

Radar Summary Charts are issued every hour

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

Describe Winds and Temperatures Aloft Forecasts (FB):

A

Winds and Temperature Aloft Forecasts (FB) depict true wind direction, wind speed and wind temperature in 3,000’ increments.

NOTE:

  • Winds and Temperature Aloft format is DDSS+/-TT
    • DD is the true direction of the wind
      • The DD will be the first 2 numbers of the true wind direction, much like how a runway is labeled (e.g. 210 = 21)
    • SS is the speed of the wind in knots
      • Winds between 100 - 199 knots are coded by adding 5 to the wind direction (e.g. 210 at 98 knots at 5 degrees celsius= 2198+05 vs 210 at 101 knots at 5 degrees celsius = 7101+05 {210 -> 21 -> 2+5=7 -> 71] )
    • TT is the temperature in celsius
      • At altitudes below FL240 the temperature will be displayed with a + or - symbol
      • At altitudes above FL240 the temperature is assumed to be negative and no + or - symbols are used (e.g. FL230 =2198-25 vs FL240 = 219825)

NOTE:

  • Winds within 1,500’ AGL are omitted
  • Temperature within 2,500’ AGL are omitted
  • Light and variable winds are displayed as 9900
  • Winds and Temperatures Aloft are issued 4 times daily
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe a Low Level Significant Weather Chart:

A

A Low Level Significant Weather Chart forecasts significant weather conditions between the surface and the 400mb pressure level (approximately 24,000’ MSL) depicting:

  • VFR
  • MVFR
  • IFR
  • Turbulence
  • Freezing levels

Each forecast is issued with both a 12 hour forecast and a 24 hour forecast for the pilot to predict weather patterns

Low Level Significant Weather Charts are issued 4 times daily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe a Mid-Level Significant Weather Chart:

A

A Mid-Level Significant Weather Chart forecasts significant weather conditions between 10,000’ MSL and F450 depicting:

  • Thunderstorms
  • Jet streams
  • Tropopause height
  • Tropical cyclones
  • Moderate to severe icing
  • Moderate to severe turbulence
  • Cloud coverage and type
  • Volcanic ash
  • Areas of released radioactive materials

Mid-Level Significant Weather Charts are issued 4 times daily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe a High-Level Significant Weather Chart:

A

A High-Level Significant Weather Chart forecasts significant weather conditions between FL250 and FL630 depicting:

  • Coverage bases and tops of thunderstorms and cumulonimbus clouds (CB)
  • Jet streams
  • Tropopause height
  • Tropical cyclones
  • Moderate to severe turbulence
  • Severe squall lines
  • Volcanic ash
  • Widespread dust or sand storms

High-Level Significant Weather Charts are issued 4 times daily

17
Q

Describe Convective Outlooks (AC):

A

Convective Outlooks (AC) are available in both graphical and textual formats. Risk for severe thunderstorm areas are classified as:

  • SLGT (slight)
  • MDT (moderate)
  • HIGH (high)

Issued:

  • 1 day outlook = 1 - 5 times per day
  • 2 day outlook = 2 times per day
  • 3 day outlook = 1 time per day
18
Q

What is the difference between a “Observation” and a “Forecast”?

A

An “Observation” is data taken from current conditions, think “weather that has been observed”

A “Forecast” is data that is expected to happen in the future

19
Q

What are the conditions necessary for the formation of thunderstorms?

A

1) Sufficient water vapor (moisture/humidity)
2) An unstable temperature lapse rate
3) An initial uplifting force (frontal passage, mountains, heating from below, etc.)

20
Q

What are hazards associated with thunderstorms?

A
  • Limited visibility
  • Wind shear
  • Strong updrafts/downdrafts
  • Icing
  • Hailstones
  • Heavy rain
  • Severe turbulence
  • Lightning strikes
  • Tornadoes
21
Q

What is the life cycle of a thunderstorm?

A

1) Cumulus stage: 3 - 5 mile height, lifting action begins, growth rate can exceed 3,000 FPM
2) Mature stage: 5 - 10 mile height, begins when precipitation begins to fall to the surface, updrafts can exceed 6,000 FPM, downdrafts can exceed 2,500 FPM, all hazards are at their greatest intensity in this stage
3) Dissipating stage: 5 - 7 mile height, characterized by strong downdrafts as the storm cell dies

22
Q

Define fog and the 5 types of fog:

A

Fog is a cloud which begins within 50’ of the surface. These clouds can form when the surface temperature reaches its dew point or when the dew point is raised to the existing temperature by added moisture to the air

  • Radiation fog: Occurs on calm clear nights when the ground cools rapidly due to the radiation of stored ground heat, lowering the temperature to the dew point
  • Advection fog: Occurs when light wind moves warm, moist air over a cold surface, lowering the temperature to the dew point
  • Upslope fog: Occurs when moist, stable air is forced up sloping terrain, lowering the temperature to the dew point via adiabatic cooling
  • Steam fog: Occurs when cold, dry air moves over warm water, raising the dew point to the air’s current temperature by added moisture
  • Ice fog: Occurs when the temperature is well below freezing and water vapor sublimates directly into ice crystals
23
Q

Define the 4 types of icing:

A
  • Structural icing:
    • Clear ice: The most dangerous type of ice, Heavy, hard, difficult to remove and often difficult to see. Forms when water drops freeze slowly as a smooth sheet of solid ice. Usually occurs at temperatures close to freeze (-10 to 0 degrees celsius) via supercooled drops of water
    • Rime ice: Opaque, white, rough ice formed by small supercooled water drops freezing quickly, usually at lower temperatures than clear ice. Danger comes from the rough surface disrupting airflow lamination, decreasing lift
    • Mixed ice: Clear and rime ice forming simultaneously
  • Instrument icing: Structural ice forming over aircraft instruments and/or sensors, such as the pitot tube or static port
  • Induction icing:
    • Intake ice: Ice restricting the engine air intake
    • Carburetor ice: Often forms due to the steep temperature drop in the carburetor venturi. Typically forms at temperatures of -7 to 21 degrees celsius with relatively high humidity, above 80%
  • Frost: Ice crystals caused by sublimation when both the temperature and dew point are below freezing
24
Q

Describe the 3 types of structural icing:

A
  • Clear ice: The most dangerous type of ice, Heavy, hard, difficult to remove and often difficult to see. Forms when water drops freeze slowly as a smooth sheet of solid ice. Usually occurs at temperatures close to freeze (-10 to 0 degrees celsius) via supercooled drops of water
  • Rime ice: Opaque, white, rough ice formed by small supercooled water drops freezing quickly, usually at lower temperatures than clear ice. Danger comes from the rough surface disrupting airflow lamination, decreasing lift
  • Mixed ice: Clear and rime ice forming simultaneously
25
Q

Describe the 2 types of induction icing:

A
  • Intake ice: Ice restricting the engine air intake
  • Carburetor ice: Often forms due to the steep temperature drop in the carburetor venturi. Typically forms at temperatures of -7 to 21 degrees celsius with relatively high humidity, above 80%
26
Q

What are the 3 RVR (Runway Visual Range) distances most often used:

A
  • RVR 1,600 = 1/4 SM visibility
  • RVR 2,400 = 1/2 SM visibility
  • RVR 5,000 = 1 SM visibility
27
Q

What are the IFR takeoff minimums?

A

Part 91 - No takeoff minimums mandated

Part 121/125/129/135 -
- The prescribed takeoff minimums for the specific runway
or, if none
- 1 or 2 engines = 1 SM visibility
- 2 or more engines = 1/2 SM visibility

28
Q

What weather conditions would mandate that an alternate airport be filed?

A

Use the “1, 2, 3” acronym:

If
- 1 hour before to 1 hour after the filed ETA
The forecasted weather is
- 2,000' AGL ceilings or less 
And/or
- 3 SM visibility or less
You must file an alternate airport
29
Q

What weather conditions must be forecast to file an airport as an alternate airport?

A

If the alternate airport has a:

  • Precision approach:
    • 600’ ceiling or greater
    • 2 SM visibility or greater
  • Nonprecision approach:
    • 800’ ceiling or greater
    • 2 SM visibility or greater
    • Must be an approach other than a non-WAAS GPS approach
  • If there is no instrument approach at the alternate:
    • Ceiling and visibility must allow descent from MEA, an approach and landing under basic VFR

IFR Refresher (4 decks)

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