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Part 107 glossary
Plain-English definitions of terms you'll meet on the test, each linked to its FAA source.
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- AGL (above ground level)
- Height measured from the ground below. Part 107's 400-foot limit is AGL. (14 CFR 107.51)
- Airport
- An area of land or water used or intended for aircraft landings and takeoffs, including its buildings and facilities. (14 CFR 1.1)
- Alert area
- Special use airspace that may hold a high volume of pilot training or unusual aerial activity. Charted as "A" plus a number. (FAA Remote Pilot Study Guide, p. 9)
- Ceiling
- The height of the lowest cloud layer reported as broken, overcast or an obscuration. (14 CFR 1.1)
- Center of gravity (CG)
- The point where all of an aircraft's weight can be considered concentrated. It moves when the load shifts. (FAA Remote Pilot Study Guide, p. 29)
- Civil twilight
- Outside Alaska: the 30 minutes before official sunrise and after official sunset. Part 107 requires anti-collision lighting then. (14 CFR 107.29)
- Class B airspace
- Controlled airspace around the busiest airports, generally from the surface to 10,000 feet MSL, in layers. (FAA Remote Pilot Study Guide, p. 5)
- Class C airspace
- Controlled airspace around busy towered airports with radar approach control, generally up to 4,000 feet above the airport. (FAA Remote Pilot Study Guide, p. 6)
- Class D airspace
- Controlled airspace around an airport with an operating control tower, generally up to 2,500 feet above the airport. (FAA Remote Pilot Study Guide, p. 6)
- Class E airspace
- Controlled airspace that isn't Class A, B, C or D. Its base is often 700 or 1,200 feet AGL. (FAA Remote Pilot Study Guide, p. 6)
- Class G airspace
- Uncontrolled airspace, from the surface up to the base of the Class E above it. (FAA Remote Pilot Study Guide, p. 6)
- Control station
- The interface the remote pilot uses to control the drone's flight path. (14 CFR 107.3)
- CTAF (Common Traffic Advisory Frequency)
- The radio frequency pilots use to announce their position and intentions at an airport without an operating control tower. (FAA Remote Pilot Study Guide, p. 40)
- Density altitude
- The altitude in the standard atmosphere that matches the current air density. Higher density altitude means thinner air and worse performance. (FAA Remote Pilot Study Guide, p. 21)
- Flight visibility
- Under Part 107, the average slant distance from the control station at which prominent objects can be seen and identified. (14 CFR 107.51)
- Load factor
- The load on an aircraft's structure compared with its weight, measured in Gs. It rises in turns and pull-ups. (FAA Remote Pilot Study Guide, p. 30)
- METAR
- A routine report of current surface weather at an airport, in a standard international format. (FAA Remote Pilot Study Guide, p. 15)
- Military operations area (MOA)
- Airspace set up to separate certain military training from IFR traffic. MOAs are named, not numbered. (FAA Remote Pilot Study Guide, p. 8)
- MSL (mean sea level)
- Altitude measured from sea level. Class B and C floors and ceilings on sectional charts are MSL. (FAA Chart Users' Guide, p. 16)
- Night
- The time between the end of evening civil twilight and the beginning of morning civil twilight. (14 CFR 1.1)
- NOTAM
- Time-critical aeronautical information that is temporary or too new to appear on charts. (FAA Remote Pilot Study Guide, p. 13)
- Prohibited area
- Airspace where flight is prohibited for security or national welfare reasons. Charted as "P" plus a number. (FAA Remote Pilot Study Guide, p. 7)
- Remote ID
- The broadcast of identification and location information that drones flying in US airspace must make, with some exceptions. (14 CFR 89.105)
- Restricted area
- Airspace with unusual, often invisible hazards such as artillery firing. You need permission from the using or controlling agency to fly there. (14 CFR 107.45)
- Sectional chart
- The FAA's VFR aeronautical chart for an area, showing airspace, airports and obstacles. It's updated every 56 days. (FAA Chart Users' Guide, p. 23)
- Small unmanned aircraft
- An unmanned aircraft weighing less than 55 pounds at takeoff, including everything on board or attached. (14 CFR 107.3)
- TAF (Terminal Aerodrome Forecast)
- A weather forecast for the area within 5 statute miles of an airport, written with the same codes as a METAR. (FAA Remote Pilot Study Guide, p. 18)
- TFR (temporary flight restriction)
- A temporary restriction on flight in an area, issued by NOTAM. Part 107 pilots must follow them. (14 CFR 107.47)
- Traffic pattern
- The traffic flow set for aircraft landing at, taxiing on, or taking off from an airport. (14 CFR 1.1)
- Unmanned aircraft
- An aircraft operated without the possibility of direct human intervention from within or on the aircraft. (14 CFR 1.1)
- Visual line of sight
- Seeing the drone with your own eyes (glasses or contacts allowed) throughout the flight, to know where it is and spot hazards. (14 CFR 107.31)
- Visual observer
- A person the remote pilot in command designates to help see and avoid other air traffic or objects. (14 CFR 107.3)