The FAA Chart Supplement

The Chart Supplement is the FAA's directory of the airports, heliports and seaplane bases open to the public in the United States, together with the navigation aids, communication facilities and procedures that serve them. Formerly called the Airport/Facility Directory (A/FD), it holds everything about an airport that a chart has no room to show: runway dimensions and surfaces, the lights and how to switch them on, frequencies, fuel and services, hours of operation, airspace status and the remarks that warn of local hazards.

For a US pilot it is the first stop when planning a flight to an unfamiliar airport. Under 14 CFR 91.103 the pilot in command must become familiar with all available information concerning a flight, including the runway lengths at the airports of intended use, and the Chart Supplement is where those lengths are published. Questions on it appear from the private pilot knowledge test onward. In ICAO States the same kind of information is in the aerodrome (AD) part of the AIP, which in some States includes visual approach charts; the FAA's product has a format and abbreviations of its own.

From A/FD to Chart Supplement

The publication was long called the Airport/Facility Directory, and older textbooks and exam questions still use that name and the abbreviation A/FD. Today the Chart Supplement U.S. is published in seven books, each covering a region of the country, and revised every 56 days, like the sectional charts. Alaska and the Pacific have supplements of their own, and the FAA also publishes the Chart Supplement online, where any entry can be found by airport.

Each book opens with a legend sample, an annotated specimen entry that decodes every element and abbreviation. The rest of the book holds information that belongs to no single airport: special notices, FAA and National Weather Service telephone numbers, aeronautical chart bulletins listing major changes since each sectional chart was printed, land and hold short operations (LAHSO) data, airport diagrams for selected towered airports, and the route, waypoint, checkpoint and parachute tables described below.

Between editions, changes reach pilots by NOTAM, and NOTAM (D) are issued for every public-use airport, seaplane base and heliport listed in the Chart Supplement. Where the Chart Supplement and the information printed on the back of a sectional chart differ, the FAA's Pilot's Handbook of Aeronautical Knowledge (PHAK) advises using the Chart Supplement, which generally holds the later information.

The airport entry and its codes

The PHAK reproduces a Chart Supplement page headed NEVADA, with entries for Alamo Landing Field (L92), Austin (TMT) and Battle Mountain (BAM). Each runs in the same order: a two-line header that identifies and locates the airport, then the runways, the airport remarks, the weather data sources, the communications and finally the radio aids to navigation. Austin's header reads AUSTIN (TMT) 4 SW UTC–8(–7DT) N39°28.08 W117°11.72 LAS VEGAS and 5735 B NOTAM FILE RNO H–3C, L–9B.

The other groups in the header, such as 4 SW, B, NOTAM FILE RNO, LAS VEGAS and H–3C, L–9B, are codes that the legend sample decodes, and a pilot new to the format reads them with the legend open.

Times are written in UTC and marked Z. Battle Mountain's entry, on the same page, says the airport is "Attended Oct–May 1500–0100Z", so the time conversion in the header is part of every reading. A sectional chart works the other way: its legend states that all times on it are local.

Battle Mountain's second line reads 4536 B S4 FUEL 100LL, JET A NOTAM FILE RNO: besides the elevation, it lists the fuel grades available. These fuel entries are why a pilot planning a fuel stop opens the Chart Supplement rather than trusting the chart. On a sectional, tick marks around an airport symbol say only that fuel is available, and the Chart Supplement says which grades. The grade matters: 100LL avgas is dyed blue and grade 100 green, while Jet A is clear or straw-colored, and a piston engine fueled with jet fuel may run briefly and then fail from detonation.

Runway data and declared distances

Each runway has its own line. Austin's reads RWY 18–36: H6000X75 (ASPH) S–30 MIRL: runway 18–36 is 6,000 ft long and 75 ft wide, surfaced with asphalt and edged by medium intensity runway lights (MIRL), the lights that Austin's remarks tell pilots to activate on the CTAF. The dirt strips at Alamo Landing on the same page read, for example, RWY 14–32: 5000X120 (DIRT). The letter in front of the dimensions and groups such as S–30, or Battle Mountain's S–30, D–104, 2S–132, are further codes explained in the legend sample.

Under each runway line come the details of its two ends: the visual glide slope indicator, runway end identifier lights (REIL) and what lies at the end, such as the "Fence" at Austin's runway 36, or the brush and the berm at the two ends of Alamo Landing's runway 14–32. Battle Mountain's runway 21 has PAPI(P4L)—GA 3.0° TCH 45', a precision approach path indicator (PAPI) giving a 3.0° visual glide path and a threshold crossing height (TCH) of 45 ft; the legend decodes P4L. Its runway 03 has a VASI instead.

Other runway information in the Chart Supplement:

• Runway slope, published when it is 0.3 percent or more. An upslope lengthens the takeoff roll; a downslope lengthens the landing roll.
• Declared distances, TORA, TODA, ASDA and LDA, where the airport publishes them. On an FAA airport diagram, a white D in a black box shows that they exist and sends the pilot to the Chart Supplement for the figures (see declared distances).
• Arresting systems, including engineered materials arresting system (EMAS) beds beyond runway ends, with the runways equipped and the type.
• The traffic pattern altitude (TPA) and pattern restrictions such as noise abatement or right-hand traffic. A sectional data block marked *RP sends the pilot to the Chart Supplement for the conditions. Where no TPA is published, AC 90-66C recommends 1,000 ft above the airport elevation for piston airplanes and 1,500 ft for large and turbine-powered airplanes.

A permanent change to a runway reaches the Chart Supplement only with its next edition. When a runway has been permanently shortened, ATC includes the word "shortened" in its clearances, as in "Runway three six shortened, cleared to land", until the Chart Supplement shows the new length.

Lighting and pilot-controlled lighting

The sectional data block only summarizes the lights: L for lighting from sunset to sunrise, *L for lighting with limitations, a dash for no runway edge lights. The limitations, such as part-time operation, lighting on request or pilot control, are spelled out in the Chart Supplement, together with the runway edge light intensity (HIRL, MIRL or LIRL), approach lights, REIL and visual glide slope indicators. Where a VASI or PAPI is offset from the extended centerline, or its obstruction clearance area has been reduced by local limitations, the Chart Supplement or a NOTAM says so (see aerodrome lighting and visual aids).

Pilot-controlled lighting (PCL) lets a pilot switch an airport's lights on from the air by keying the microphone on a published frequency. The Chart Supplement gives the lights and the frequency in remarks such as Austin's "ACTIVATE MIRL Rwy 18–36, PAPI Rwys 18 and 36, REIL Rwy 18 and 36—CTAF." The frequency is often the CTAF but not always, and it is not shown on sectional charts; instrument approach charts give it too. All radio-controlled lighting at one airport works on the same frequency.

The lights stay on for 15 minutes from the most recent activation. The AIM recommends keying seven times first, so that every controlled light comes on at full intensity, then adjusting. Because receivers are often set to low sensitivity, so that aircraft at neighboring airports on the same frequency do not trigger them, the pilot keys again when overflying the airport or just before the final approach segment, which also restarts the 15 minutes. Where an airport without an instrument approach has a non-standard system installed by its sponsor, the Chart Supplement describes the lights, the method of control and the frequency in plain text.

Communications and services

The communications section lists the frequencies a pilot may need at the airport: the CTAF, UNICOM, ATIS, tower, ground control, clearance delivery, and approach and departure control. Austin lists only "CTAF 122.9", which is MULTICOM, used where there is no tower, flight service station (FSS) or UNICOM. Battle Mountain's "CTAF/UNICOM 122.8" shows a UNICOM frequency serving as the CTAF, and its entry adds a remote communications outlet (RCO) for Reno Radio, a flight service station, and Salt Lake Center for approach and departure control.

The common traffic advisory frequency (CTAF) is the frequency designated for airport advisory practices where no control tower is operating. It may be a UNICOM, MULTICOM, FSS or tower frequency, FSS frequencies being available only in Alaska. For a part-time tower, the Chart Supplement gives the hours and what applies when the tower is closed: the "Airspace" entry reads "other times Class E" or "other times Class G", and the tower frequency normally becomes the CTAF (see communications at non-towered aerodromes).

For IFR departures, the entry gives the frequency or telephone number for obtaining a clearance at an airport without an operating tower, and may also give a number for canceling the IFR flight plan after landing. The Chart Supplement also identifies automated UNICOM systems, terminal radar service areas (TRSA) and the airports where approach control sequences VFR arrivals. The weather data sources line gives the automated station, such as an AWOS or ASOS, with its frequency and telephone number.

Services appear in the header and in the remarks: whether the airport is attended and when, whom to call after hours, and limits such as "no line service after 1800". Austin's remarks begin with a single word, "Unattended".

The radio aids section lists the navaids serving the airport, with their class, frequency and identifier, their bearing and distance to the field, and any parts of their service volume found unusable. Battle Mountain's VORTAC, for example, is unusable in three sectors, beyond 15 or 30 NM, below 12,000 ft. Such restrictions are first published by NOTAM and then appear with the navaid in the Chart Supplement.

Notices and special procedures

Airport remarks are where local hazards are written down. On the PHAK's sample page, Alamo Landing's remarks warn that the field is unattended, that vehicles have uncontrolled access, that there is no line of sight between the runway ends and that livestock are in the vicinity of the runways; Austin's note that military aircraft operate near the airport. Other remarks carry:

• wildlife warnings, such as deer on and in the vicinity of the airport; the AIM notes that collisions with large animals on runways have occurred at major airports as well as rural ones
• prior permission required (PPR) procedures, with a telephone number or frequency for coordinating them
• traffic pattern restrictions and noise abatement procedures
• at airports with LED approach lighting, the warning "Pilots conducting EFVS ops; be aware LED ALS in use", since infrared-based enhanced flight vision systems cannot sense LED lights.

The special sections support planning beyond the destination:

• VOR receiver checkpoints, ground and airborne, and VOT test facilities, with the areas and altitudes where a VOT may be used in the air. Under 14 CFR 91.171 the error must not exceed ±4° at a ground checkpoint or VOT, or ±6° at an airborne checkpoint (see VOR).
• Parachute jumping areas, listed in the Chart Supplement, whereas only frequently used sites are depicted on sectional charts.
• Preferred IFR routes, established in the major terminal and en route environments, on which ATC bases IFR clearances unless severe weather avoidance procedures or other factors dictate otherwise.
• VFR waypoints, whose published coordinates let a pilot check a waypoint in an outdated GPS database against an official source.
• Airports with conventional approaches kept under the VOR minimum operational network (MON), for pilots reverting to VOR navigation when GPS is unreliable.

Read together with the NOTAMs, the Chart Supplement answers most of a pilot's questions before arriving somewhere new: whether the runway is long enough, which lights there are and how to turn them on, which frequency to call, whether there is fuel, and what the locals already know about the place.

Library articles are written for study and exam preparation. They do not replace your aircraft's approved documentation, your operator's procedures or the regulations themselves.