PPL PPL Flight Instruments and Weather 3 — Questions and Answers
Question 1: What does a rapidly falling barometric pressure typically indicate?
- An approaching low-pressure system with deteriorating weather (Correct answer)
- Improving, stable conditions
- A high-pressure ridge building
- No significant weather change
Correct answer: An approaching low-pressure system with deteriorating weather
Falling pressure usually signals an approaching low and worsening weather.
Question 2: Around a high-pressure system in the Northern Hemisphere, surface winds circulate in which direction?
- Clockwise and outward (Correct answer)
- Counterclockwise and inward
- Clockwise and inward
- Straight from north to south
Correct answer: Clockwise and outward
Highs produce clockwise, outward-flowing surface winds in the Northern Hemisphere.
Question 3: The dew point is best described as the temperature at which the air becomes:
- Saturated and condensation begins (Correct answer)
- Completely dry
- Warmest for the day
- Unable to hold any moisture at altitude
Correct answer: Saturated and condensation begins
At the dew point the air reaches 100% relative humidity and moisture begins to condense.
Question 4: A small spread between temperature and dew point most likely indicates the possibility of:
- Fog or low clouds (Correct answer)
- Clear skies and high visibility
- Strong turbulence
- Rapid warming
Correct answer: Fog or low clouds
A narrow temperature/dew-point spread favors fog and low ceilings.
Question 5: Which cloud type is associated with thunderstorms and potential hazards like hail and wind shear?
- Cumulonimbus (Correct answer)
- Cirrus
- Stratus
- Altocumulus
Correct answer: Cumulonimbus
Cumulonimbus clouds contain thunderstorms with hazards such as hail, lightning, and severe turbulence.
Question 6: Stable air masses are generally characterized by:
- Stratiform clouds, steady precipitation, and poor visibility (Correct answer)
- Cumuliform clouds and gusty winds
- Good visibility with strong vertical currents
- Frequent thunderstorms
Correct answer: Stratiform clouds, steady precipitation, and poor visibility
Stable air produces layered stratiform clouds, steady precipitation, and often reduced visibility.
Question 7: What is the standard temperature and pressure at sea level in the International Standard Atmosphere?
- 15°C and 29.92 inHg (Correct answer)
- 0°C and 30.00 inHg
- 20°C and 29.92 inHg
- 15°C and 28.00 inHg
Correct answer: 15°C and 29.92 inHg
The ISA sea-level standard is 15°C and 29.92 inches of mercury.
PPL PPL Flight Instruments and Weather 3
What does a rapidly falling barometric pressure typically indicate?