Other hazardous Meteorological Conditions Flashcards
Explain the methods by which the aviation community is advised of volcanic eruptions within the New Zealand FIR.
- Volcanic Ash Advisory, MetService, Wellington
- SIGMETs and SIGWX
- NOTAMs
- Volcanic Ash Advisory Group found of VAAC
Explain the hazards to aviation of volcanic ash encountered in flight.
- Onboard weather radar can’t see volcanic ash
- Engine flame out
- Reduced visibility
- Scoring of windscreens
- Pitot blockage
- ‘Sandblast’ effect on airframe and antennae
- Oil contamination
- Smoke smell
Explain the hazards to aviation of volcanic ash encountered during the take-off and landing phases on ash contaminated runway.
- Volcanic ash is a mixture of rock, mineral, and glass particles
- Avoid ingesting stirred up ash from the runway
- Taxi slow and accelerate slowly if possible
- Avoid using reverse thrust
- Wet ash is more slippery than dry on the ground
Explain the development of, and the hazards associated with, flight in dust storms.
- Occur in hot dry environments during the day (not hugely relevant to NZ)
- Air needs to be unstable to lift dust off the ground
- Associated with gust fronts in a thunderstorm during the mature stage
- Reduce visibility to less than 1,000m and strong winds
- Engine damage due to ingesting dust
Explain the development of, and the hazards associated with, flight in blowing surface snow (blizzards).
- Blizzards are violent storms combining below-freezing temperature with strong winds and blowing snow that has already fallen
- Blowing snow: An ensemble of snow particles raised by the wind to moderate or great heights above the ground
- Vertical visibility dismissed, horizontal visibility is very poor
- Caused by strong continuous winds of at least 56km/h
- Last for threes hours or more
- Snow is not falling but loose snow on the ground is lifted and blown by strong winds
- METAR code = BLSN
Explain the development of, and the hazards associated with, flight in whiteouts (visual illusion type)
- Occurs in overcast conditions over snow
- Now shadows or visible objects resulting in spatial disorientation
- Can make it impossible to navigate visually even though visibility is high
Describe the effects of volcanic ash on aircraft operations.
- Fan blades eroded
- Poor radio reception
- St Elmo’s fire (blue electrical tendrils)
- Fire warning alarms may go off due to smoke sized particles
Explain the development of and sector whiteout.
- Sector whiteout - occurs in overcast conditions above dust, sand, mudflats, or glassy water
- Creates flat light conditions
- Lose depth-of-field and contrast in vision
Describe the hazards of flight in whiteout conditions.
- Disorientation
- Falsely identifying the ground
- Unaware of any approaching terrains
- Unaware if straight and level
With reference to Space Weather, list the different type of Space Weather.
- Coronal Mass Ejections = 24hrs to reach earth
- Solar Flares = 8 minutes to reach earth
- Solar Energetic Particles = continuous
- Galactic Cosmic Rays (from distant supernovae outside of solar system)
- Solar Radiation = 11 year cycle in instensity
What are the effects of Coronal Mass Ejections (CME)?
- Large expulsions of plasma and magnetic field from the Sun’s corona (outermost layer of a star’s atmosphere)
What are the effects of Solar Flares?
- A sudden flash of increased brightness on the Sun
- Accompanied by a coronal mass ejection
What are the effects of Solar Energetic Particles?
- High-energy particles flowing continuously from the Sun.
How does Space Weather affect aircraft navigation?
- Degraded performance of navigation and surveillance that rely on GNSS
- Automatic Dependent Surveillance - Broadcast (ADS-B) anomalies
- Sporadic loss-of-shock of GNSS
- Solar and galactic
How does Space Weather affect aircraft communications?
- Unexpected loss of communications
- HF voice and HF data link can fail (3-30MHz)
- VHF less likely to be impacted
- Caused by solar flare enhancing electron density in the atmosphere and also galactic cosmic rays
How does Space Weather affect ATC radar coverage?
- Ghosting of radar coverage, Position of aircraft different to what is being shown on radar.
- Cause by solar and galactic
How does Space Weather affect aircraft pilots and passengers?
- High does of ionising radiation
- Can increase chances of developing skin cancer.
- Enhanced at higher altitudes and higher latitudes
- Caused by solar and galactic
