CPC Weather Interpretation & Meteorology for Controllers 2 — Questions and Answers
Question 1: What is wind shear and why is it critical information for approach controllers?
- A change in wind direction only, affecting ground roll
- A sudden change in wind speed and/or direction that can cause rapid airspeed changes on approach (Correct answer)
- A steady crosswind component above 15 knots
- Turbulence caused by mountain wave activity
Correct answer: A sudden change in wind speed and/or direction that can cause rapid airspeed changes on approach
Wind shear is a sudden change in wind velocity or direction that can cause dangerous airspeed fluctuations during approach and departure phases.
Question 2: A microburst is characterized by which feature that makes it particularly dangerous?
- Wide coverage area over 20 miles
- A downdraft that produces increasing headwind then rapid tailwind loss (Correct answer)
- Slow formation over several hours
- Occurring only at high altitudes
Correct answer: A downdraft that produces increasing headwind then rapid tailwind loss
A microburst produces an initial performance-increasing headwind followed by a severe performance-decreasing tailwind, making it extremely hazardous on approach.
Question 3: When should a controller issue a low-level wind shear (LLWS) advisory to pilots?
- Only when requested by the pilot
- Whenever PIREPs or LLWAS alerts indicate wind shear below 2,000 ft AGL (Correct answer)
- Only when visibility drops below 1 mile
- When surface winds exceed 25 knots
Correct answer: Whenever PIREPs or LLWAS alerts indicate wind shear below 2,000 ft AGL
Controllers must promptly relay wind shear advisories when LLWAS alerts or PIREPs report wind shear conditions below 2,000 ft AGL.
Question 4: What does a pilot report of 'moderate icing in cloud' indicate to an approach controller?
- Icing is cosmetically visible but not hazardous
- Ice accumulation is rapid enough to affect performance and may warrant re-routing (Correct answer)
- Only light aircraft are affected
- Conditions are within normal operation for all aircraft
Correct answer: Ice accumulation is rapid enough to affect performance and may warrant re-routing
Moderate icing means ice accumulates rapidly enough to require frequent use of de-icing equipment and may be hazardous if prolonged, warranting consideration of alternate routing.
Question 5: What weather phenomenon is associated with a temperature inversion and can produce smooth but disorienting flying conditions?
- Mountain wave turbulence
- Radiation fog and restricted visibility (Correct answer)
- Convective cells
- Jet stream turbulence
Correct answer: Radiation fog and restricted visibility
Temperature inversions trap moisture near the surface, producing radiation fog and significantly restricted visibility, especially in early morning hours.
Question 6: Which automated system at airports provides real-time wind shear detection data to controllers?
- ATIS
- LLWAS (Low Level Wind Shear Alert System) (Correct answer)
- ACARS
- TDWR alone
Correct answer: LLWAS (Low Level Wind Shear Alert System)
The Low Level Wind Shear Alert System (LLWAS) uses a network of anemometers to detect surface wind shear and provides real-time alerts to controllers.
CPC Weather Interpretation & Meteorology for Controllers 2
What is wind shear and why is it critical information for approach controllers?