Airspace

Reading it off the chart

Nearly every airspace question on the Remote Pilot test is really a chart question. The supplement gives you a sectional excerpt and asks what class of airspace a point sits in, so the colours and line styles are the actual skill:

Numbers stacked in a box, like 70 over SFC, give the ceiling over the floor in hundreds of feet MSL. A magenta [12] style box near an airport gives the floor of the overlying Class E. Everything on a sectional is MSL unless it is followed by AGL.

Airspace classification — UA.II.A

Controlled airspace (K1a–d)

For a remote pilot the practical difference between B, C, D and surface E is almost nil: all four require prior ATC authorization under § 107.41. What differs is where they sit and what they look like.

• Class B — the busiest airports, an upside-down wedding cake to 10,000 ft MSL. Solid blue.
• Class C — typically a 5 NM inner core to 4,000 ft AGL and a 10 NM shelf. Solid magenta.
• Class D — a towered field, roughly 4 NM radius to about 2,500 ft AGL. Dashed blue. It reverts to Class E or G when the tower closes, which does not remove your § 107.41 obligation if the airspace is still charted as D.
• Class E — controlled airspace that is not A, B, C or D. Only Class E designated to the surface requires authorization. Class E that begins at 700 or 1,200 ft AGL does not, because you are beneath it at 400 ft.

Class G (K1e)

Uncontrolled. No ATC authorization required, and this is where most drone flying happens. It still carries the § 107.51 weather minimums, and it still carries every other rule in Part 107 — uncontrolled does not mean unregulated.

Special-use airspace (K2)

• Prohibited — no flight, period (P-40, P-56).
• Restricted — hazards to flight; entry needs the controlling agency's permission. Charted R-xxxx.
• Warning — the same activity as restricted, but over international waters where the US cannot prohibit entry.
• MOA — military training. Not prohibited, but assume high-speed military traffic that is not looking for you.
• Alert — unusual volume or type of activity; everyone remains responsible for their own separation.
• Controlled firing area — the only one not charted, because activity stops when an aircraft approaches.

Other airspace areas (K3)

• MTRs — military training routes. IR/VR with four digits means at or below 1,500 ft AGL; three digits means above. Four digits is the one that concerns you.
• TFRs — temporary flight restrictions. Stadiums, VIP movement, disaster areas, wildfires. Check before every flight; a TFR can appear the same day.
• Parachute jump areas, TRSAs, NSAs and VFR routes are charted and worth recognising, though none carry a Part 107 authorization requirement of their own.

ATC and the NAS (K4)

Authorization for controlled airspace comes through LAANC (Low Altitude Authorization and Notification Capability) for near-instant approval up to the charted grid ceiling, or through FAA DroneZone for anything LAANC cannot grant. You do not talk to the tower for a Part 107 authorization — a phone call to ATC is not an authorization.

Airspace operational requirements — UA.II.B

Weather minimums (K1)

§ 107.51: 3 statute miles visibility from the control station, and cloud clearance of 500 ft below and 2,000 ft horizontally. Also 400 ft AGL maximum, or within 400 ft of a structure, and 87 knots groundspeed maximum.

ATC authorizations (K2) and operations near airports (K3)

Authorization is airspace-specific and altitude-specific. Near an airport, § 107.43 is the one that catches people out: you must not interfere with operations and traffic patterns at any airport, heliport, or seaplane base — the rule names all three, and a heliport with no runway and no tower is still covered — and that applies in Class G, where no authorization was needed in the first place. Being legal to be there is not the same as being clear of the traffic pattern.

Potential flight hazards (K4)

• Accident causal factors (K4a) — overwhelmingly human: poor preflight, loss of situational awareness, pressing on.
• Unmanned balloons (K4b) — do not fly beneath one; the tether or payload may be invisible.
• Emergency airborne inspection (K4c) — if asked to inspect another aircraft, approach from a position that keeps you clear and visible.
• Precipitation static (K4d) — charge buildup in precipitation; interferes with radio and can degrade the control link.
• Lasers (K4e) — report any laser illumination to ATC or the FSDO. Do not look at the source.
• Thermal plumes (K4f) — smoke stacks and cooling towers produce invisible, violent vertical currents well above the structure. A small aircraft has no margin for one.
• The wire environment (K4g) — wires are effectively invisible from the air and from a camera feed. Look for the structures — poles, towers, cleared right-of-way — and infer the wire, because you will not see the wire itself.

NOTAMs (K5)

Notices to Air Missions, available through Flight Service (1-800-WX-BRIEF) or online. TFRs arrive as NOTAMs, which is why checking them is not optional.

Night operations, lighting and ground hazards (K6–K10)

• sUAS lighting (K10) — § 107.29 requires anti-collision lighting visible for at least 3 statute miles for night and civil twilight operations. Since the 2021 rule change no waiver is needed for night, but the lighting and the training are.
• Manned aircraft lighting (K9) — red left, green right, white tail. If you see red and green side by side and steady, it is pointing at you.
• Ground structures and their lighting (K7, K8) — towers over 200 ft carry lights, but guy wires do not, and many obstacles below 200 ft carry nothing at all. Unlit hazards are the norm, not the exception, and they are why a daylight site survey is worth more than any amount of night caution.
• Operator equipment (K6) — your own night kit: a lit control station you can read without destroying your dark adaptation, and a way to keep the aircraft in sight.