When you spread a VFR aeronautical chart across your lap or open one on an EFB, you are looking at one of the most carefully engineered safety tools in aviation. The FAA publishes several types of VFR charts, and two of the most important for private pilots are the Sectional Aeronautical Chart and the Terminal Area Chart (TAC). At first glance they look similar — both show airports, airspace, terrain, obstacles, and navigation aids using the same color-coded symbology. The critical difference lies in scale, coverage area, and intended use. Understanding when to reach for each one, and how to read the information it carries, is both a practical navigation skill and a popular topic on the FAA Private Pilot Knowledge Test.
This article breaks down the purpose, design, and content of each chart type, highlights the differences that matter most in the cockpit, and flags the exam traps that catch students off guard.
Sectional Aeronautical Charts: The VFR Backbone
Sectional Charts — often called simply "sectionals" — are the standard VFR chart for cross-country flight across the contiguous United States, Alaska, and Hawaii. They are produced at a scale of 1:500,000, meaning one inch on the chart equals approximately 6.86 nautical miles on the ground. The entire lower 48 states is divided into 37 named sectionals (e.g., Los Angeles, Chicago, New York), each covering a large geographic region. Charts are updated on a 56-day cycle and must be current to be used for navigation — carrying an expired chart is not technically prohibited by regulation, but the FAA strongly advises using current editions because airspace, frequencies, and obstacle data change regularly.
At the 1:500,000 scale, sectionals show an enormous amount of information: airports with runway lengths and lighting, Class B/C/D/E/G airspace boundaries, VORs, NDBs, and GPS waypoints, MOAs, restricted areas, prohibited areas, wildlife refuges, power lines, towers, terrain contours with elevation tints, and much more. Pilots learn to read the chart's legend carefully, because the same symbol can carry multiple layers of meaning depending on color, shape, and line style. For example, Class D airspace is depicted with a dashed (segmented) blue circle, while Class E airspace starting at the surface is depicted with a dashed magenta circle.
Sectionals are ideal when you are planning a cross-country flight covering dozens or hundreds of miles. Their broad coverage lets you see the big picture — where the mountain ranges are, which airspace boundaries you will cross, where alternate airports lie, and what terrain you need to clear. The tradeoff is that detail near large, complex airports becomes compressed and harder to read at this scale.
Terminal Area Charts: Zoomed In on Complexity
Terminal Area Charts (TACs) solve exactly that problem. Published at a scale of 1:250,000 — twice as large as a sectional — a TAC shows twice as much physical detail for the same printed area. One inch on a TAC represents approximately 3.43 nautical miles on the ground. This larger scale gives pilots a much cleaner picture of the highly congested airspace around the nation's busiest airports.
TACs are published specifically for areas surrounding Class B airspace. Because Class B airspace consists of multiple floors and ceilings arranged in a layered, upside-down wedding cake configuration, and because dozens of satellite airports, VFR corridors, and transition routes may exist within a small geographic radius, compressing all of that onto a sectional makes it nearly unreadable. The TAC spreads it out so that each individual shelf of the Class B, each underlying Class C and D airport, and each VFR waypoint or flyway can be depicted clearly and accurately.
TACs are also updated on a 56-day cycle, synchronized with sectionals. The FAA currently publishes TACs for approximately 30 metropolitan areas, including Chicago, Los Angeles, Dallas-Fort Worth, Atlanta, New York (two charts — NY and NY Helicopter), Miami, and others. Not every Class B airport gets a TAC — some are covered adequately on the sectional — but every TAC location has Class B airspace at its core.
What's the Same on Both Charts
The symbology used on sectionals and TACs is identical. The same magenta and blue airport symbols, the same airspace boundary line styles, the same VOR compass roses, the same obstacle depiction conventions — all are standardized across both chart types. A student who learns to read a sectional can transfer that skill directly to a TAC without relearning the legend from scratch. This consistency is intentional and important: in busy airspace, a pilot should not have to mentally translate between different symbol systems.
Both charts also display the same categories of aeronautical information: communication frequencies, ATIS and ASOS information, terrain elevation data, special use airspace, and notes about local procedures. Maximum elevation figures (MEFs), shown in large blue numbers by quadrangle, appear on both charts and represent the highest known elevation within that grid square including terrain and obstacles, rounded up for a safety buffer.
Key Numbers and Rules
- Sectional scale: 1:500,000 (approximately 6.86 nm per inch)
- TAC scale: 1:250,000 (approximately 3.43 nm per inch)
- Update cycle: Both are revised every 56 days
- TAC coverage: Published for approximately 30 major Class B airspace areas
- When a TAC is required: No regulation requires a specific chart type, but operating within Class B airspace without an accurate and current depiction of its boundaries is operationally hazardous and likely a deviation waiting to happen
- Class B entry: 14 CFR 91.131 requires an ATC clearance and, for student pilots, a logbook endorsement; having the TAC for that airspace helps you understand exactly which clearance you need and where each shelf begins and ends
- VFR flyways: TACs often include VFR flyway planning charts printed on the reverse side, showing recommended VFR routes around or through Class B airspace at specified altitudes
The VFR Flyway Planning Chart: A TAC Bonus
One of the most useful features associated with TACs is the VFR Flyway Planning Chart, printed on the reverse side of most TACs. This supplemental chart, also at 1:250,000 scale, shows suggested VFR routes for pilots who wish to transit the vicinity of a major terminal area without entering Class B airspace. The routes are depicted with recommended altitudes and prominent visual checkpoints. These are not regulatory routes — you are not required to follow them — but they represent the routes ATC prefers and expects from VFR pilots transiting the area. Using a VFR flyway significantly reduces the risk of an inadvertent Class B incursion.
Why It Matters: Safety and Airspace Compliance
The stakes around Class B airspace are high. An inadvertent penetration of Class B without a clearance is a violation of 14 CFR 91.131, which can result in certificate action. More practically, Class B exists around the busiest commercial airports in the country, where airliners on ILS approaches may be descending through altitudes that VFR traffic could occupy. The precision that a TAC provides — depicting exactly where each shelf of the Class B begins and ends, which satellite airports sit inside or beneath the outer layers, and where VFR transition corridors exist — is the kind of precision that keeps small aircraft out of harm's way.
When planning a flight that will take you within roughly 30–40 miles of a major Class B airport, it is best practice to have both the relevant sectional (for the big picture) and the TAC (for the detailed local picture) available. Many EFB applications display both chart types and allow you to zoom seamlessly between them.
Common Test Traps
- Confusing the scales: Students frequently reverse the scales. Remember: TAC = 1:250,000 (larger scale, more detail), Sectional = 1:500,000 (smaller scale, broader coverage). A larger representative fraction number means a smaller scale and less detail.
- Assuming TACs cover all busy airports: TACs are published only for areas with Class B airspace, not for every Class C or D airport. A busy regional airport with Class C airspace is depicted on the sectional only.
- Thinking different symbology is used: TACs and sectionals use identical symbology. The only difference is scale and geographic coverage.
- Forgetting the VFR flyway chart: The FAA knowledge test may ask about what is found on the reverse side of a TAC. The answer is the VFR Flyway Planning Chart, not a helicopter route chart or instrument approach procedure.
- Currency confusion: Both charts update every 56 days. This is not the same as the 28-day cycle used for IFR en route low/high altitude charts or approach plates. Using an expired VFR chart is not explicitly prohibited by FAA regulation, but it is operationally unsafe and the FAA expects pilots to use current charts.
Mastering the relationship between sectionals and TACs is more than a test-prep exercise. Every time you plan a flight anywhere near a major metropolitan area, you are making a practical decision about which tool gives you the resolution you need to stay oriented, legal, and safe. Treat them as complementary instruments in your navigation toolkit — one shows you the forest, the other shows you the trees.