International airports, regional fields and GA aerodromes — the places every mission starts and ends.

| Company | Type | Location | Codes |
|---|---|---|---|
| Ominato Airbase | aerodrome | Japan | ICAO RJSO |
| Omio | aerodrome | South Sudan | — |
| Omni Airport | aerodrome | United States | — |
| Omni Ranch Ultralight Flightpark | aerodrome | Edinburg, United States | — |
| Omolon Airport | aerodrome | Russia | ICAO UHMN |
| Omora Airport | international | Papua New Guinea | IATA OSE · ICAO AYOM |
| Omsk-Centralny Airport | international | Russia | IATA OMS · ICAO UNOO |
| Omsukchan airport | international | Russia | ICAO UHMF |
| Omura Air Base | international | Japan | IATA OMJ · ICAO RJDU |
| Ona Airpark | aerodrome | United States | — |
| Onaiso (Etosha West) Airfield | aerodrome | Namibia | — |
| Oncheon Airport |
aerodrome 30,878international 8,351military airfield 1,867private airstrip 1,800heliport 555regional 460
United States 15,232Brazil 2,982Australia 2,025Canada 1,765France 1,355Russia 1,265United Kingdom 1,109South Africa 938Germany 879Colombia 835Italy 718Indonesia 681Argentina 621Ukraine 570Papua New Guinea 536China 489Mexico 478Venezuela 468Spain 414India 411Namibia 376Chile 358Congo - Kinshasa 356South Sudan 331Poland 327Czechia 277New Zealand 250Kenya 242Sweden 222Japan 195Philippines 188Norway 179Botswana 151Portugal
Operators claiming an entry can correct facts, add services and certificates, and mark their page verified. Claiming is free — see a company’s page for the claim link.
| military airfield |
| North Korea |
| — |
| Ondangwa Airport | international | Namibia | IATA OND · ICAO FYOA |
| Onderombapa Airstrip | aerodrome | Namibia | — |
| Öndörkhaan Airport | international | Mongolia | IATA UNR · ICAO ZMUH |
| Onduli Ridge Airstrip | aerodrome | Namibia | — |
| Ondundu Lodge Airstrip | aerodrome | Namibia | — |
| Ondwa Airport | aerodrome | India | ICAO VA1H |
| O Neal Field | aerodrome | United States | — |
| One Arm Point Airport | aerodrome | Australia | ICAO YOAP |
| Onecoat Morridge Airstrip | aerodrome | United Kingdom | — |
| Onega | aerodrome | Онега, Russia | ICAO ULAO |
| Onega Andozero | military airfield | Russia | — |
| One Grand Field | aerodrome | United States | — |
| O'Neill Municipal Airport | international | United States | IATA ONL · ICAO KONL |
| Onenui Station | aerodrome | New Zealand | — |
| Oneonta Municipal Airport | international | United States | IATA ONH |
| Ongava Airstrip | international | Namibia | IATA OGV · ICAO FYNG |
| Ongino Airstrip | private airstrip | Uganda | — |
| Ongjin Airport | aerodrome | North Korea | — |
| Onguma Airfield | aerodrome | Namibia | ICAO FYGG |
| Onida Municipal Airport | aerodrome | United States | — |
| Onion Crest Airpark | aerodrome | Kearney, United States | — |
| Onjala Airstrip | aerodrome | Namibia | — |
| Onjoka Airstrip | aerodrome | Namibia | — |
| Ono Gliderport | aerodrome | Japan | — |
| Ono-i-Lau Airport | international | Fiji | IATA ONU · ICAO NFOL |
| Onomichi Floating Port | aerodrome | Japan | — |
| Onondaga Lake Seaplane Base | aerodrome | United States | — |
| Ononge Airport | international | Papua New Guinea | IATA ONB · ICAO AYQQ |
| Onotoa Airport | international | Kiribati | IATA OOT · ICAO NGON |
| Onseepkans Airstrip | aerodrome | South Africa | — |
| Onslow Airport | international | Australia | IATA ONS · ICAO YOLW |
| Onslow Memorial Hospital Heliport | aerodrome | United States | — |
| Ontario International Airport | international | United States | IATA ONT · ICAO KONT |
| Ontario Municipal Airport | international | United States | IATA ONO · ICAO KONO |
| On the Rocks Airport | aerodrome | Alpine, United States | — |
| Ontonagon County Airport | aerodrome | United States | ICAO KOGM |
| Ontong Java Airport | private airstrip | Solomon Islands | ICAO AGGQ |
| Onya | aerodrome | Indonesia | — |