Weather

Question 1

What frequency band is typically used for VOLMET broadcasts

Answer 1

High Frequency (HF) and sometimes Very High Frequency (VHF), depending on the area and coverage required.

Question 2

1-What measured friction coefficient values can typically be expected in a runway condition report

2-What do the values indicate

3-How is friction measured

Answer 2

1-0.20-0.50, depending on surface type, contamination, and weather conditions

2-Low (~0.20-0.30): Poor braking - wet, icy, or contaminated runway.
Medium (~0.30-0.40): Reduced braking - damp or lightly contaminated.
High (~0.40-0.50+): Good braking - dry or cleared runway.

3-Using continuous friction measuring devices (CFMD) or Mu-meter type equipment.

Question 3

What is D-ATIS

Answer 3

Data Link Automatic Terminal Information Service - pre-recorded aerodrome information (weather, runway, NOTAMs) delivered digitally to the cockpit via data link.

often integrated with CPDLC or datalink systems for cockpit display, reducing voice frequency congestion.

Question 4

Which 8 meteorological phenomena must an aircraft in flight report as a Special Weather Report (SPECI / PIREP)

Answer 4

-Severe turbulence or mountain wave turbulence
-Severe icing or freezing rain
-Severe or extreme convective activity (thunderstorms, squall lines)
-Embedded CB
-Volcanic ash
-Sandstorms or dust storms reducing visibility
-Tropical cyclones or squall lines
-Any other weather considered significant for flight safety

Question 5

1-What is VOLMET

2-What information is typically contained in a VOLMET broadcast

Answer 5

1-Meteorological information provided to aircraft in flight

2-Type of report (METAR or SPECI).

Surface wind, Visibility, Cloud, Temperature, Dew Point, QNH

Significant weather

Trend forecast (if available)

Question 6

What is ACARS

Answer 6

Aircraft Communications Addressing and Reporting System - a digital data link system that automatically transmits and receives messages between the aircraft and ground stations, including flight plans, weather, maintenance reports, and operational information

Question 7

How is minimum visibility recorded in a METAR

Answer 7

Minimum visibility is reported in meters (or statute miles in some countries) and reflects the lowest horizontal visibility observed on the aerodrome, often including prevailing visibility, direction, and any variations

Question 8

How is visibility expressed when:
1-Below 800m
2-Between 800m and 5000m
3-Above 5000m

Answer 8

1-Reported in steps of 50 m (eg. 0400 for 400 meters).

2-Reported in steps of 100 m (eg. 4500 for 4500 meters).

3-Reported in steps of 1 km (eg. 8000 for 8 km)

Question 9

How are cloud octas reported in a METAR

Answer 9

Sky Clear 0
FEW 1-2
SCT 3-4
BKN 5-7
OVC 8

Question 10

How is the cloud base above an aerodrome reported in a METAR

Answer 10

In hundreds of feet above aerodrome elevation for each significant cloud layer

Question 11

What are the different classifications of turbulence
What actions are required by the pilots?

Answer 11

Light turbulence - Slight, momentary changes in altitude or attitude; slight bumpiness; little or no change in control
Maintain course, monitor

Moderate turbulence - Greater intensity than light; changes in altitude/attitude noticeable; aircraft remains in positive control; occupants feel definite strain
Adjust speed if needed; report to ATC if requested

Severe turbulence - Large, abrupt changes in altitude/attitude; aircraft may be momentarily out of control; occupants are forced violently against seat belts
Use appropriate turbulence penetration speed; report to ATC

Extreme turbulence - Aircraft is completely out of control; may cause structural damage
Emergency procedures; immediate ATC report

Question 12

What is the highest cloud-base altitude that will be reported on an ATIS as “cloud of operational significance”

Answer 12

Cloud will be reported if the base is below 1 500 m (≈ 5 000 ft) above the surface, or below the highest minimum sector altitude (whichever is greater), or it is a cumulonimbus cloud at any height

Question 13

How long is a “NOSIG” forecast valid on a METAR

What does NOSIG apply to

What happens if conditions are expected to change before the expiry of the NOTAM

Answer 13

NOSIG indicates that no significant change in weather is expected for the next 2 hours from the time of observation.

Applies to wind, visibility, weather, and cloud conditions.

If conditions are expected to change significantly within 2 hours, a new METAR or trend forecast will be issued.

Question 14

1-What is required for the transmission of a routine or special meteorological report
2-How often must the report be made when en-route and during the climb out phase

Answer 14

1-The a/c must have an air-ground data link
2-Automated routine observation should be made every 15 minutes in the en-route phase, and every 30 seconds during the climb-out phase for the first 10 minutes of the flight