Part 107 Weather Flashcards
Standard air temperature and pressure at sea level
15 degrees Celsius at 29.92 inches of Mercury
The height an object is at above ground level. That is, you could be at 2000 feet MSL but when you’re drone is still on the ground, you and the drone are at 0 AGL.
Absolute altitude
The height of an object or location above MSL. It is the actual level above sea level you and your drone are at. So if you are launching at 2000 feet MSL then 2000 feet MSL Is your….altitude
True altitude
The height or altitude your altimeter displays. Regarding drone flight, most altimeters assume you are at sea level under standard conditions, where ——— altitude is the same as true altitude
Indicated altitude
The indicated altitude when the barometric pressure scale is set to 29.92 inches of Mercury. It doesn’t determine temperature
Pressure altitude
The pressure altitude corrected for non standard temperature. The altitude that we’ve said that the drone feels like it’s flying
Density altitude
A hot humid day would have this affect on an drone
May accelerate more slowly or may need to move faster making it more difficult for the drone to climb
What type of air does high density altitude refer to
Thin air
What type of air does low density altitude refer to
Dense air
You will experience reduced aircraft performance in what type of density altitude
High density altitude
You will have stronger performance in what type of density altitude
Lower density altitude
Higher density altitude means thinner air and results in ————drone performance
Reduced drone performance
Lower density altitude means thicker dense air and ————- performance
Stronger
The climb performance of an drone ————— with altitude
Diminishes with altitude
———/- currents are the forces that cause bumpy turbulent air when flying at lower altitudes during warmer weather
Convective currents
Every change in weather is the direct result of
A heat exchange
Stable air tends to produce
Stratiform clouds
Smooth air
Fair to poor visibility with haze and smoke
Continuous precipitation
Unstable air tends to produce
Cumuliform clouds
Turbulent air
Good visibility
Showery precipitation
Air mass that brings cool dry air. It forms over ———regions
Polar air mass
An air mass that brings warm moist air. It forms over ———- waters
Tropical air mass
Air mass that causes good surface visibility but has turbulence, cumulus clouds, and showers
Unstable air mass
This weather front brings low ceilings, poor visibility, and rain, move slowly
Warm front
This weather front brings sudden storms, gusty winds, turbulence, and sometimes hail or tornadoes , move quickly
Cold front
———- can occur at any altitude. Can affect flight at any altitude
Wind shear
The changing of liquid water to water vapor is called
Evaporation
The changing of ice to water vapor bypassing the liquid stage is
Sublimation
These are the most dangerous type of cloud appearing individually or in groups as either air mass or orographic thunderstorms . Think marshmallows
Cumulonimbus clouds
Nimbus means
Rain
These clouds are formed by barriers in the wind flow and are most prevalent around mountaintops. Often called standing clouds. They are good indication of strong turbulence and should be avoided
Lenticular
What is the most violent time of a thunderstorms life cycle
Mature stage
You must operate at least ——-feet below clouds
500 feet
How to reach the cloud base AGL
Temperature minus dew point is spread. Divide the spread by 4.4 if temperatures are in farenheit or 2.5 if temps are in Celsius and then multiply by 1000 for the cloud base AGL
What is a characteristic of stable air?
Cumulus nimbus clouds
Stratiform clouds
Unlimited visibility
Stratiform clouds
What are the characteristics of a moist unstable air mass?
Poor visibility and smooth air
Cumuliform clouds and showery precipitation
Stratiform clouds and showery precipitation
Cumuliform clouds and showery precipitation
If an unstable air mass is forced upward what type of clouds can be expected?
1) clouds with considerable vertical development and associated turbulence
2) cumulus clouds with little vertical development
3) stratus clouds with considerable associated turbulence
Clouds with considerable vertical development and associated turbulence
A stable air mass is likely to have which characteristic
Turbulent air
Showery precipitation
Poor surface visibility
Poor surface visibility
Moisture is added to air by
Evaporation and sublimation
Evaporation and condensation
Sublimation and condensation
Evaporation and sublimation
Which combination of atmospheric conditions will reduce aircraft takeoff and climb performance?
1) high temperature, low humidity, low density altitude
2) high temp, high humidity and high density altitude
3) low temp, low humidity, and low density altitude
High temp, high humidity, high density altitude
What effect does high density altitude have on a propeller?
1) efficiency is increased
2) density altitude does not effect propeller efficiency
3) propeller efficiency is decreased
Propeller efficiency is decreased
Generally for aircraft the most hazardous kind of thunderstorm is
Stratiform thunderstorm
Squall line thunderstorm
Warm front thunderstorm
Squall line thunderstorm
What should you expect if you see lenticular clouds over a mountain?
Light to moderate precipitation
Strong turbulence
The beginning of a thunderstorm
Strong turbulence
Which is formally defines as “pressure altitude corrected for nonstandard temperature variations”
True altitude
Pressure altitude
Density altitude
Density altitude
What is the indicated altitude when your altimeter is set to 29.92
Density altitude
Indicated altitude
Pressure altitude
Pressure altitude
What is the standard air temperature and pressure at sea level?
32 degrees Celsius and 30.00 hg
15 degrees Celsius and 29.92 hg
98.6 degrees
15 degrees Celsius and 29.92 hg
In a metal report what does BR indicate
Must
TAFs are typically valid for
24 or 30 hour time period
To obtain a complete weather overview for a planned flight the remote pilot in command should obtain
Standard briefing
Which weather service provides current recorded weather information
ATIS automated weather reporting
