Lesson 15

Question 1

What is the altitude range of a GFA?

Answer 1

GFA charts describes the most likely meteorological conditions expected to occur between the
surface and 24 000 feet over a given area during a specific time frame.

Question 2

There are two types of GFA charts that are used together. What are they?

Answer 2

• Clouds and Weather (CLDS, WX)
• Icing, Turbulence, and Freezing Level (ICG, TURB, and FZLVL)

Question 3

A SIGMET is issued whenever at least 1 of 12 phenomena has been reported or is
expected to occur within the next four hours. Name 4 of these

Answer 3

• Areas of active thunderstorms
• Lines of thunderstorms
• Hurricanes and tropical storms
• Heavy hail
• Severe turbulence (not associated with convective clouds)
• Severe icing (not associated with convective clouds)
• Marked mountain waves
• Widespread sand or dust storms
• Volcanic ash cloud*
• Low-level wind shear
• Severe squall line
• Tornado or waterspout

Question 4

There are three main SIGMET types. What are they?

Answer 4

• WS: thunderstorm (TS), turbulence
  (TURB), icing, (ICG), mountain waves
  (MTW), low-level wind shear (LLWS),
  dust storm (DS), sand storm (SS),
  radioactive cloud (RDOACT CLD),
  squall line (SQLN)
• WV: volcanic ash (VA)
• WC: tropical cyclone (TC)

Question 5

There are two possible Canadian PIREP types. What are they?

Answer 5

• Routine—coded as UACN10
• Urgent—coded as UACN01

Question 6

There are two possible international PIREP types. What are they?

Answer 6

• Routine—coded as UA
• Urgent—coded as UUA

Question 7

What times are GFAs issued?

Answer 7

The GFA charts are issued at 0530, 1130, 1730, and 2330 UTC for 0600, 1200, 1800, and 0000 UTC respectively.

Question 8

ATS personnel must take any report of clear ice formation seriously and pass this information on to:

Answer 8

• Concerned aircraft
• The position designated the responsibility for disseminating weather information, if applicable
• Other concerned sectors or units, if the weather is of significance
• The appropriate FIC

Question 9

When pilots report turbulence, ATS personnel must file a turbulence report that should contain:

Answer 9

• Time in UTC
• Location(s) of turbulence (indicates whether the turbulence is over a single location or between two locations)
• Duration of turbulence
• Whether or not the turbulence is in clouds
• Altitude
• Type of aircraft
• Intensity*
  *In addition to reporting intensity, turbulence may be described as:
• Occasional (OCNL)—less than one-third of the time
• Intermittent (IMTNT)—one-third to two-thirds of the time
• Continuous (CONTUS)—more than two-thirds of the time

Question 10

What are the 7 distinct areas for the GFAs and their codes?

Answer 10

Pacific GFACN31
Prairies GFACN32
Ontario et Quebec GFACN33
Atlantic GFACN34
Yukon and NWT GFACN35
Nunavut GFACN36
Arctic GFACN37