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Answer:

1. Fog:
   • Forms when air temperature and dew point are nearly equal, reducing visibility to less than 5/8 SM.
2. Mist:
   • Similar to fog but with higher visibility (5/8 to 6 SM) and smaller water droplets.
3. Haze:
   • Caused by suspended dry particles such as dust, salt, or smoke, reducing visibility in stable air.
4. Smoke:
   • Produced by fires or industrial activity and can reduce visibility significantly, especially in light winds.
5. Precipitation:
   • Rain, snow, or drizzle can reduce visibility, especially heavy rain or snow showers.
6. Blowing Snow:
   • Snow lifted by the wind, reducing visibility and creating whiteout conditions.
7. Dust Storm:
   • Strong winds lift large amounts of dust, severely reducing visibility and creating hazardous flight conditions.
8. Sandstorm:
   • Similar to a dust storm but with fine sand particles, mainly in desert regions.
9. Volcanic Ash:
   • Extremely hazardous to aviation; can cause engine failure, obscure visibility, and damage aircraft surfaces.

Answer:

Yes, frost is hazardous to flight because it affects aerodynamic performance by:

• Disrupting smooth airflow over the wings, leading to early airflow separation.
• Reducing lift and increasing stall speed.
• Potentially preventing takeoff at normal speeds, even with a small amount of frost.
• Decreasing stall margin in flight, making the aircraft more susceptible to stalling in turns or turbulence.

Answer:

• Definition:
  • Frost consists of ice crystal deposits that form through sublimation when both temperature and dew point are below freezing.
• Formation Conditions:
  • Occurs on clear nights when moisture is present in the air.
  • Radiational cooling causes the aircraft’s skin temperature to drop below freezing, allowing moisture to freeze directly onto the surface.

Answer:

1. Radiation Fog:
   • Forms at night or near daybreak under clear skies, little or no wind, and high humidity.
   • Caused by ground cooling, which lowers air temperature to the dew point.
2. Advection Fog:
   • Develops when moist air moves over colder ground or water.
   • Common in coastal areas but can form inland.
   • Can occur day or night and with wind present.
3. Upslope Fog:
   • Forms when moist, stable air is lifted up a slope or terrain and cools adiabatically.
   • Dissipates when upslope winds stop.
4. Frontal Fog (Precipitation-Induced Fog):
   • Forms when warm, moist air is lifted over a front, producing clouds and precipitation.
   • If cold air below is near the dew point, evaporation from precipitation can saturate the air and create fog.
5. Steam Fog:
   • Occurs when very cold air moves over warmer water.
   • Moisture evaporates, rises, and immediately re-condenses, forming fog that rises like steam.
6. Freezing Fog:
   • Forms when supercooled fog droplets freeze upon contact with surfaces.
   • Occurs when air temperature is at or below 0°C (32°F).
   • Can cause dangerous icing on aircraft and runways.

Answer:

• Fog Formation:
  • Occurs when air temperature and dew point become equal (or nearly so).
  • Can happen in two ways:
    1. Cooling the air below its dew point (radiation fog, advection fog, or upslope fog).
    2. Adding moisture to raise the dew point (frontal fog or steam fog).

Answer:

• Definition:
  • A temperature inversion occurs when temperature increases with altitude, reversing the normal lapse rate.
• Types and Effects:
  • Inversion Aloft:
    • Allows warm rain to fall through colder air below, which can lead to freezing rain and icing hazards.
  • Ground-Based Inversion:
    • Traps fog, smoke, and pollutants, leading to poor visibility.
    • Creates stable air conditions with little to no turbulence.

Answer:

• Exit the Icing Conditions:
  • Leave the area of precipitation to avoid further ice accumulation.
  • Change altitude to reach warmer air above freezing.
• If Unable to Exit:
  • Consider an immediate landing at the nearest suitable airport.
• Additional Considerations:
  • If the aircraft has anti-ice or de-ice systems, activate them.
  • Monitor airspeed, control responsiveness, and climb performance.
  • Communicate with ATC for assistance in finding a safer route or altitude.

Answer:

• Definition:
  • The freezing level is the lowest altitude where the air temperature reaches 0°C.
  • Multiple freezing levels can exist due to temperature inversions.
• Determining the Freezing Level:
  • Current Icing Products (CIP) and Forecast Icing Products (FIP).
  • Freezing Level Graphics Chart – Provides a visual representation of freezing altitudes.
  • Graphical Forecasts for Aviation (GFAs) – Displays freezing levels across a flight region.
  • PIREPs – Pilot reports on in-flight icing conditions.
  • AIRMETs and SIGMETs – Identify areas of known or forecast icing hazards.
  • Surface Analysis Charts – Help locate cold air masses.
  • Low-Level Significant Weather Charts – Show freezing levels in the lower atmosphere.
  • Winds and Temperatures Aloft Forecasts – Indicate air temperatures at various altitudes.

Answer:

1. Clear Ice (Glaze Ice):
   • Glossy, transparent, or translucent ice that forms slowly as large, supercooled water droplets freeze gradually.
   • More common in warmer temperatures (closer to freezing), high liquid water content, and large droplets.
   • Can be hard to detect and difficult to remove, increasing aircraft weight and disrupting aerodynamics.
2. Rime Ice:
   • Rough, opaque, and milky ice that forms instantly when small, supercooled water droplets freeze on impact.
   • Occurs in colder temperatures with lower liquid water content and smaller droplets.
   • More common and easier to remove than clear ice but still disrupts airflow over the aircraft.
3. Mixed Ice:
   • A combination of clear and rime ice, forming uneven and rough ice layers.
   • Occurs in variable temperature and moisture conditions, where both large and small droplets exist.
   • Can create aerodynamic and control issues due to its irregular shape and weight buildup.

• General Temperature Ranges for Icing Types:
  • Rime ice: Colder than -15°C.
  • Clear ice: Warmer than -10°C.
  • Mixed ice: Between -15°C and -10°C.

Answer:

1. Structural Icing:
   • Forms on the airframe, wings, propeller, and control surfaces.
   • Disrupts aerodynamic flow, reducing lift and increasing drag.
2. Induction System Icing:
   • Occurs in the engine’s air intake, restricting airflow.
   • Includes carburetor icing, which can cause engine power loss or failure.
3. Instrument Icing:
   • Forms on pitot tubes, static ports, and antennas.
   • Can lead to incorrect instrument readings, affecting airspeed, altitude, and climb/descent indications.