How to read a sectional chart for the Part 107 test

A sectional chart packs a lot onto one sheet, so scan it the same way every time: first the airspace boundaries, then the numbers printed on them, then the nearest airport and any tall obstacles, converting heights as you go. The conversion matters because your drone's 400-foot limit is measured above the ground (14 CFR 107.51(b)), while the chart mostly works in feet above mean sea level (MSL). It matters for the test, too. Starting October 26, 2026, the FAA says the Unmanned Aircraft General (UAG) test adds image-based questions that aren't in the test supplement, with images taken from the latest sectional charts (FAA advisory, August 2026, p. 6). Expect to see a chart excerpt you have never studied.

The basics, before any symbols

• Scale: 1:500,000 (Chart Users' Guide, p. 10). One inch on the chart covers 6.86 nautical miles, roughly 8 statute miles (FAA Remote Pilot Study Guide, p. 67).
• Editions: a new one every 56 days (AIM 9-1-5). Check the dates printed on the chart and fly with the current edition (Chart Users' Guide, p. 6).
• Default units: unless a note says otherwise, distances are nautical miles, altitudes are MSL and times are UTC (Chart Users' Guide, p. 6).
• Legend: it is printed on the chart, and it is how you learn to recognize aeronautical, terrain and obstruction symbols (Chart Users' Guide, p. 10).

Step 1: sort the boundaries by color and style

• Solid blue: Class B (Chart Users' Guide, p. 26).
• Solid magenta: Class C (Chart Users' Guide, p. 27).
• Dashed blue: Class D (Chart Users' Guide, p. 16).
• Dashed magenta: Class E that starts at the surface (Chart Users' Guide, p. 17).
• Shaded magenta band (a vignette): Class E with a floor of 700 feet above ground level (AGL). A blue vignette marks a different floor next to Class G, and some higher floors carry a number instead. Unless the chart designates something else, Class E exists from 1,200 feet AGL (Chart Users' Guide, p. 17).
• Nothing at all: Class A, which visual charts leave off (Chart Users' Guide, p. 16).

Roughly speaking, the solid lines belong to the big airports, the dashed lines bring controlled airspace down to the ground, and the shaded bands keep it off the ground. Of all these, Part 107 asks for ATC authorization only inside the Class B, C and D boundaries and the dashed magenta Class E surface area (14 CFR 107.41). Our guide to Part 107 airspace explains the reasoning.

Step 2: read the numbers on the boundaries

Each Class B and Class C sector carries two figures, top over bottom, in hundreds of feet MSL (Chart Users' Guide, p. 16). So 80 over 40 means 4,000 to 8,000 feet MSL. Four marks change how you read them (Chart Users' Guide, p. 16):

• SFC on the bottom: the sector starts at the ground.
• + in front of a Class B floor: the floor is "upward from above" that value, so that altitude and anything lower are outside the Class B.
• T as a Class C top: it rises to the floor of the Class B overhead without including it.
• A minus sign before a Class D top: the airspace runs from the ground up to just short of that figure.

Step 3: turn MSL into AGL

Add the ground elevation at your launch point to the height you plan to fly, then compare the total with the floor above you. Remember that Class C and Class D limits are set relative to the airport's elevation but printed as MSL (FAA Remote Pilot Study Guide, p. 6).

Picture a field under a Class C outer ring labeled 50 over 25, with the ground at roughly 700 feet MSL. Climbing to 400 feet AGL puts you at 1,100 feet MSL, well short of the 2,500-foot floor. That leaves one question: what begins at the ground there? If the field lies within a magenta vignette and outside every dashed line, the Class E floor is 700 feet AGL (Chart Users' Guide, p. 17), so at 400 feet you are in Class G.

Step 4: the airport and its data

Color tells you about the tower: blue airports have one, magenta airports don't (Chart Users' Guide, p. 15). The text beside the symbol adds detail (Chart Users' Guide, p. 15):

• CT and a frequency: the tower's main frequency. A star means the tower isn't open all the time; the chart's table of tower frequencies gives its hours.
• A letter C in a filled circle placed just after a frequency shows that it is the Common Traffic Advisory Frequency (CTAF).
• Elevation: the highest point of the usable landing area.
• L and *L: runway lights from sunset to sunrise; with the asterisk, lighting is limited in some way and the Chart Supplement has the details.
• Runway figure: the longest runway, in hundreds of feet.

RP with runway numbers flags right-hand traffic patterns (Chart Users' Guide, p. 16). Airports without a working tower use a CTAF for traffic advisories, and it can be a UNICOM, MULTICOM, flight service or tower frequency (FAA Remote Pilot Study Guide, p. 65). The AIM encourages drone operators near an airport to monitor it for awareness, but tells them not to radio or phone ATC to get airspace access (AIM 11-8-2). Whatever the airport, never interfere with its traffic pattern (14 CFR 107.43).

Step 5: obstacles and the highest ground

Man-made obstacles are generally charted once they stand more than 200 feet AGL, or more than 299 feet AGL within a city's yellow tint (Chart Users' Guide, p. 11). Where the FAA knows both values, the upper number is the top of the obstacle in feet MSL and the number in parentheses below it is its height above the ground (Chart Users' Guide, p. 11). The difference is the ground elevation at its foot: an obstacle labeled 2210 over (480) stands on ground at 1,730 feet MSL and rises 80 feet higher than the usual 400-foot AGL limit.

• UC means the obstacle is being built, or has been reported but not yet checked (Chart Users' Guide, p. 11).
• Where obstacles crowd together, as in a city, the chart may show only the tallest one (Chart Users' Guide, p. 11).
• Turbine blade tips carry no lights, and the hub lights can sit 200 to 300 feet lower than the tips in some cases (Chart Users' Guide, p. 11).
• Guy wires on a tower can reach about 1,500 feet sideways, so the study guide says to give such structures at least 2,000 feet horizontally, and a brand-new tower may be missing from your chart (FAA Remote Pilot Study Guide, p. 70).

Every block of 30 minutes of latitude by 30 minutes of longitude, marked off by ticked lines, also shows a maximum elevation figure (MEF): the highest terrain or obstacle in that block, rounded up to the next 100 feet and printed without its last two digits (Chart Users' Guide, p. 12). Read it as a height above sea level, not above your launch point.

Step 6: special use airspace, and what charts leave out

Special use areas carry their type and name or number on the chart (Chart Users' Guide, p. 17); restricted areas, for instance, appear as R plus a number (FAA Remote Pilot Study Guide, p. 8). Tables on the chart give each one's altitudes, hours of use and controlling agency, and the FAA doesn't issue NOTAMs to announce those listed hours (Chart Users' Guide, p. 20). Temporary flight restrictions mostly don't appear at all: only those tied to national security are charted (Chart Users' Guide, p. 18). Between editions, the FAA wants pilots checking NOTAMs (Chart Users' Guide, p. 6). Our guide to special use airspace and TFRs covers what each type means for a drone.

Practice on current chart crops

Chart reading improves with repetition, and from October 26 the test uses images from the latest charts (FAA advisory, August 2026, p. 6). Our Part 107 chart questions use crops of current FAA sectionals, and the October 2026 test changes guide explains what is new. Check a symbol you don't know in the glossary, then take the free Part 107 practice test. For two full lessons on sectional charts and a chart trainer, Part 107 Complete is a one-time $39.

Questions people ask

Are sectional chart altitudes in MSL or AGL?

Unless the chart says otherwise, altitudes are in feet above mean sea level. Obstacles also show their height above the ground in parentheses under the MSL figure.

What does a magenta vignette mean on a sectional?

It marks Class E airspace that begins at 700 feet above ground level. A dashed magenta line, by contrast, marks a Class E surface area that starts at the ground.

How often are sectional charts updated?

Every 56 days. Always use the current edition and check NOTAMs for changes between editions.

Will the Part 107 test show sectional chart images?

Yes. The FAA says that from October 26, 2026, the UAG test includes image-based questions not found in the test supplement, using images from the latest sectional charts.