Aviation & Maritime

Aviation & Maritime#

Reference of identifier systems for aircraft, ships, airports, and ports, the codes operators use during tracking, OSINT, incident analysis, and regulatory work.

For sensor / receiver hardware (ADS-B, AIS), see SDR Hardware. For tracking math, see Triangulation. For data sources (FlightAware, MarineTraffic, Sentinel-1 SAR), see OSINT Sources.

Aviation: aircraft#

Identifier

Notes

ICAO 24-bit hex

unique per airframe (e.g. AA1234); transmitted on ADS-B, Mode S; the standard “airframe” identifier.

Tail / registration

national civil registration: N-prefix (US), G- (UK), D- (DE), F- (FR), VH- (AU), JA- (JP), B- (CN/TW), HL- (KR), PT/PR/PP- (BR), C- (CA), VT- (IN), HZ- (SA). Painted on tail.

Mode S address

same as ICAO 24-bit hex.

Squawk

4-digit transponder code (Mode A); 7500 hijack, 7600 lost comms, 7700 emergency, 1200 VFR (US), 7000 VFR (EU).

Flight number

airline operator (DL123); IATA / ICAO airline prefix + number. Reused across days.

Callsign

flight number / military / ATC sign as transmitted.

ATC callsign

3-letter ICAO airline code + flight number (DAL123 = Delta 123).

Selcal

4-letter HF selective-call code.

Aviation: airports#

Code

Notes

ICAO airport code

4-letter (KJFK, EGLL, ZBAA, OMDB, RJTT). Region prefix: K-=US (lower 48), C-=Canada, E-=Northern Europe, L-=Southern Europe, U-=Russia, O-=Middle East, V-=South Asia, Z-=China, R-=Japan/Korea/Philippines, F-=southern Africa, S-=South America, M-=Central America/Caribbean, A-=Pacific.

IATA airport code

3-letter (JFK, LHR, PEK, DXB, HND); the consumer code.

FAA LID

US-only 3-4 character (e.g. KORD ICAO = ORD IATA = KORD FAA).

Aviation: airlines#

Code

Notes

IATA airline (2-letter)

AA, BA, DL, UA, LH, AF, KL, EK, QF, SQ, JL, NH, CX, CA, MU, CZ, QR, EY, TK.

ICAO airline (3-letter)

AAL, BAW, DAL, UAL, DLH, AFR, KLM, UAE, QFA, SIA, JAL, ANA, CPA, CCA, CES, CSN, QTR, ETD, THY.

ICAO callsign

AMERICAN, SPEEDBIRD, DELTA, UNITED, LUFTHANSA, AIRFRANCE, KLM, EMIRATES, QANTAS, SINGAPORE, JAPANAIR, ANA, CATHAY, AIR CHINA, CHINA EASTERN, CHINA SOUTHERN, QATARI, ETIHAD, TURKAIR.

Aviation: data sources#

Source

Notes

FlightAware

live + history; US-friendly.

Flightradar24

live + history; large global coverage.

ADS-B Exchange

community-fed; does not filter military / blocked. Often the only source for sensitive flights.

OpenSky Network

academic / non-commercial; raw ADS-B archive.

ADS-B Hub

community feed.

RadarBox

commercial / community.

PlaneFinder

commercial.

ICAO ADS-B mandates

US 2020, EU 2017+, others phasing.

LiveATC.net

crowd-sourced ATC audio.

Aerosky / Skyvector

flight planning + charts.

Aviation: spectrum#

Band

Notes

108 - 117.95 MHz

VOR navigation aid (3 letter ID Morse).

118 - 137 MHz

Civil aviation VHF AM voice.

121.5 MHz

Aero emergency (still monitored).

121.95 - 121.9

Ground.

243 MHz

Military aero emergency; 2nd harmonic of 121.5.

328.6 - 335.4 MHz

ILS Glideslope.

406 MHz

Cospas-Sarsat ELT (replaces 121.5 satellite-detected).

978 MHz

ADS-B UAT (US below 18,000 ft).

1090 MHz

Mode S / ADS-B (universal).

1030 MHz

Secondary radar interrogation.

1.5 GHz

Inmarsat Aero (cockpit comms).

Maritime: ships#

Identifier

Notes

IMO number

7-digit unique-per-hull from IMO; persists through name / ownership changes (e.g. IMO 9301568).

MMSI

9-digit Maritime Mobile Service Identity for AIS / VHF DSC; first 3 digits = MID country code (e.g. 366 = US, 232-235 = UK, 244-246 = NL, 211 = DE).

Call sign

ITU-prefix radio callsign (V- = UK, KA-W = US, J = Japan, D = Germany, BO-BQ = China, etc.).

Hull number

national construction number; not unique globally.

Flag

country of registration; “flag of convenience” common (Liberia, Panama, Marshall Is., Bahamas, Malta, Cyprus).

Class

classification society (Lloyd’s, DNV, Bureau Veritas, ABS, ClassNK, RINA).

Maritime: AIS message types#

Class

Notes

Class A

SOLAS-mandated; commercial vessels >300 GT international / 500 GT cargo / passenger ships. 12.5 W TX.

Class B

smaller vessels / leisure; lower power; less frequent updates.

AIS aids-to-nav

buoys + lighthouses with AIS.

AIS-SART

search-and-rescue transmitter.

AIS spoofing

easily spoofed; multiple state-actor incidents (Black Sea, Strait of Hormuz, Vatican-spoofed Russian ships 2022+).

Maritime: ports & locations#

Code

Notes

UN/LOCODE

5-letter alphanumeric (CCLLL): US LAX = USLAX, NL Rotterdam = NLRTM, SG Singapore = SGSIN, CN Shanghai = CNSHG / CNSHA.

IMO Port Reference

IMO-issued port codes (less common in public use).

ENI number

European Number of Identification; inland waterways.

Lloyd’s port-code

commercial registry.

Maritime: data sources#

Source

Notes

MarineTraffic

live + history; commercial; community-fed AIS.

VesselFinder

similar.

Spire Maritime

commercial AIS satellite + terrestrial.

Equasis

IMO ship database (search by IMO).

ITU MARS

MMSI registry.

Lloyd’s List Intel.

commercial maritime registry.

S&P Global Sea-web

commercial.

Global Fishing Watc h

AIS-based fishing-vessel tracking; OSS.

windy.com / windwar d

weather + tracking.

ShipFinder

consumer-front-end.

NOAA AIS

US national AIS data.

EMSA SafeSeaNet

EU port / vessel data (gov access).

Maritime: spectrum#

Band

Notes

2 - 27.5 MHz

HF marine voice / data; long range.

156.025-162.025 MHz

VHF marine; channels 1-28 + 60-88; Ch 16 = 156.8 distress.

161.975 + 162.025

AIS (channels 87 + 88).

406 MHz

EPIRB (Cospas-Sarsat).

1.5 GHz

Inmarsat-C ship-to-shore.

9 GHz

X-band marine radar.

3 GHz

S-band marine radar.

Operator notes#

  • ICAO 24-bit hex is the durable airframe ID; tail registration changes when the aircraft is re-registered.

  • Blocked flights, US PIA program / EU equivalents conceal owners; ADS-B Exchange does not honor blocks.

  • Military aircraft, often filter from FlightAware / Flightradar24; ADS-B Exchange + OpenSky show them. Some fly with transponder off entirely.

  • AIS gaps, coastal terrestrial AIS coverage drops far from shore; satellite AIS (Spire, ORBCOMM, exactEarth) fills in; vessels still spoof, dark-go, or substitute MMSIs.

  • Dark fleets, sanctioned-trade vessels (Russia / Iran / Venezuela / DPRK oil) routinely spoof AIS or run dark; OFAC / EU / UK lists publish indicators; satellite imagery + SAR (Sentinel-1, ICEYE, Capella) are the detection tools.

  • Mode S extended squitter, ADS-B Out is mandated in most regions; carriers without it (older GA, military) appear only on multilateration.

  • Spoofing, AIS spoofing is trivial (commodity SDR); ADS-B spoofing is straightforward but quickly noticed by multilateration cross-check.

References#

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