polar route

In August 1935, the Soviet aviator Sigizmund Levanevsky and his two crewmen attempted a transpolar flight from Moscow, Russian SFSR, Soviet Union to San Francisco, California. The flight was aborted because of technical issues before they reached the North Pole.{{facts|date=October 2022}} In 1936, Levanevsky and navigator Victor Levchenko completed a more-than-{{convert|11800|mi|adj=on|order=flip|}} multistage flight from Los Angeles to Moscow in a Vultee V-1A floatplane, thus proving the possibility of an air route between the United States and the Soviet Union via the Bering Strait.{{facts|date=October 2022}}

Another Soviet pilot Valery Chkalov and his crew were the first to fly non-stop from Europe to the American Pacific Coast. {{ill|Transpolar flight of Chkalov, Baydukov and Belyakov|lt=Their flight|ru|Беспосадочный перелёт Москва — Северный полюс — Ванкувер}} from Moscow to Vancouver, Washington, United States, via the North Pole on a Tupolev ANT-25 single-engine plane (June 18–20, 1937) took 63 hours to complete. The distance covered was {{convert|8811|km|mi}}.{{Cite book|title = Red Arctic : Polar Exploration and the Myth of the North in the Soviet Union, 1932–1939|last = McCannon|first = John|publisher = Oxford University Press|year = 1998|isbn =978-0-19-535420-1|location = New York|page = 71|url = https://books.google.com/books?id=u1OyKDItM5wC&pg=PA71}} The following month, another Soviet crew led by Mikhail Gromov {{ill|Transpolar flight of Gromov, Yumashev and Danilin|lt=retraced the transpolar route|ru|Беспосадочный перелёт Москва — Северный полюс — Сан-Джасинто}}, extending the distance to the world record-breaking 10,148 kilometers (6,302 miles), landing near San Jacinto, California, in the United States.{{facts|date=October 2022}} In August of the same year, another Soviet crew led by Sigizmund Levanevsky started its long distance transpolar flight from Moscow to Fairbanks, Alaska; the radio communication with the aircraft broke off beyond the North Pole, and all subsequent search missions failed.{{facts|date=October 2022}}

In October 1946, a modified B-29 flew {{convert|9422|mi|km|order=flip}} nonstop from Oahu, Hawaii, to Cairo, Egypt, in less than 40 hours, further proving the capability of routing airlines over the polar icecap.[https://books.google.com/books?id=NSEDAAAAMBAJ&pg=PA91 "Inside The Dreamboat."] Popular Science, December 1946 interview with crew about planning for flight.

File:And-your-name-will-be-Leif-Viking-391772977037.jpg was the first airplane to use the polar route for regular flights. Here Leif Viking becomes christened by Cyd Charisse on 18 November 1954.]]

Of the commercial airlines, SAS was first: their Douglas DC-6B flights between Los Angeles and Copenhagen, via Kangerlussuaq and Winnipeg, started on November 15, 1954.{{Cite web| url=http://www.flightglobal.com/pdfarchive/view/1954/1954%20-%203146.html | title=Denmark—Greenland—U.S.A. | access-date=2015-03-05 | archive-date=2017-08-21 | archive-url=https://web.archive.org/web/20170821050020/https://www.flightglobal.com/pdfarchive/view/1954/1954%20-%203146.html | url-status=dead}} Canadian Pacific DC-6Bs started Vancouver–Amsterdam in 1955, then Pan Am and TWA started West Coast to Paris/London in 1957. SAS was first again, flying Europe to Tokyo via Anchorage with Douglas DC-7Cs in February 1957; Air France Lockheed L-1649 Starliner (which was the final version of the Lockheed Constellation) and KLM DC-7C aircraft followed in 1958.{{cite web|url=https://blog.klm.com/to-tokyo-with-a-dc-7-over-the-north-pole/|title=To Tokyo with a DC-7 over the North Pole|date=23 November 2014|website=KLM Blog |last1=Ogier |first1=Frido }} Air France was the first to operate commercial jet service over the North Pole on the routing Tokyo – Anchorage – Hamburg – Paris on 18 February 1960 using Boeing 707-328 Intercontinental equipment.

During the Cold War, the Arctic region was a buffer zone between the Soviet Union and North America. Civilian flights from Europe to the Asian Far East were prohibited from crossing the Eastern Bloc countries, Soviet Union or China,{{Citation needed|date=October 2021|reason=Air France started to fly to Beijing from 1966, Swissair started flights to China in 1970s, and there are TWA flights from US cities to Shanghai in 1980s.}} and had to fly either via the Middle East or across Arctic North America and Greenland with a refueling stop in Anchorage. These Cold War tracks extended from the northern Alaskan coast across Greenland to Europe. In 1978, Korean Air Lines Flight 902 operated with a Boeing 707 was shot down over the USSR by a Soviet Air Force fighter aircraft after the flight crew made gross navigational errors attempting to fly the assigned polar route.{{facts|date=October 2022}}

In April 1967 Japan Air Lines (JAL) began an experimental service between Tokyo and Europe via Moscow across Siberia. This service used an Aeroflot Tupolev Tu-114, with one JAL flight crew and mixed JAL and Aeroflot cabin crew. However, Japan Air Lines dropped the service in 1969.{{facts|date=October 2022}}

During the Cold War, Anchorage International Airport (ANC) in Alaska was a technical stop for a number of airlines flying the polar route between western Europe and Tokyo. According to the July 1, 1983 edition of the Worldwide Official Airline Guide (OAG), Air France, British Airways, Japan Air Lines (JAL), KLM Royal Dutch Airlines, Lufthansa, Sabena and Scandinavian Airlines (SAS) were all operating flights between Japan and western Europe which included a stop in Anchorage.http://www.departedflights.com, July 1, 1983 Worldwide Official Airline Guide (OAG), Tokyo-Anchorage flight schedules Most of these international airlines were operating earlier model Boeing 747 aircraft on the route at this time, although Sabena and SAS were instead operating McDonnell Douglas DC-10-30 aircraft on their respective polar route services via Anchorage. U.S. based air carrier Western Airlines also flew a polar route during the early 1980s between London Gatwick Airport and Honolulu using DC-10-30 aircraft, with these flights also making a stop in Anchorage.http://www.departedflights.com, March 1, 1981 Western Airlines system timetable

The only airline that still flies this type of route between Europe and Anchorage is Condor Airlines, seasonal service between Frankfurt (EDDF) and Anchorage.{{cite press release |title=StackPath (12 August 2020) |url=https://www.aviationpros.com/airports/press-release/21150014/anc-condor-announces-2021-anchorage-flights |website=www.aviationpros.com |access-date=21 August 2020}} This will soon be joined by a flight by Eurowings, also from Frankfurt, using an Airbus A330.{{update inline|date=August 2020}}

Finnair was the first airline to fly non-stop via the polar route without a technical stop. This service began in 1983 and was flown with a McDonnell Douglas DC-10-30ER wide body jetliner between Tokyo and Helsinki.http://www.departedflights.com, July 1, 1983 Worldwide Official Airline Guide (OAG), Tokyo-Helsinki flight schedules{{cite journal | last = Huhtanen | first = Ann-Mari | date = 7 September 2014 | title = Perhana, se tulee suoraan kohti. Jouluna 1987 Finnairin lento AY 915 oli matkalla Tokiosta Helsinkiin, kun Huippuvuorten kohdalla konetta lähestyi ohjus | trans-title = ‘Damn it, it's coming straight at us. At Christmas, 1987, Finnair flight AY 915 was en route from Tokyo to Helsinki, when a missile approached it over Svalbard’ | journal = Helsingin Sanomat | pages = C 6–8 | publisher = Sanoma | access-date = 2014-09-21 | url = http://www.hs.fi/sunnuntai/a1409895098937 | language = fi | archive-date = 2016-03-04 | archive-url = https://web.archive.org/web/20160304071539/http://www.hs.fi/sunnuntai/a1409895098937 | url-status = dead }}

United States Boeing B-52 aircraft operated in the Arctic Ocean region almost continuously in the 1960s as part of Operation Chrome Dome and in later decades as part of readiness exercises. A number of Western reconnaissance aircraft also conducted missions regularly along the Soviet Union's northern coast. Russian Long-Range Aviation now perform some of the same types of training flights, testing the readiness of Alaskan Command and Royal Canadian Air Force interceptors.[https://www.adn.com/alaska-news/military/2017/04/21/russian-military-planes-intercepted-off-alaska-for-4th-straight-night/ Russian military planes approach Alaska for 4th straight night], Anchorage Daily News, Published April 21, 2017.

Starting 1 May 1992, Aeroflot began regular flights between Moscow and San Francisco via Anchorage in both directions. These flights were operated by IL-62 aircraft which didn't have long enough range to fly nonstop between Moscow and San Francisco.{{cite book |title=Aeroflot Worldwide Timetable, 29 March - 24 October 92 |publisher=Aeroflot Soviet Airlines}} The Moscow-Anchorage and Anchorage-Moscow legs were, at the time, the scheduled passenger airline routes that came closest to the North Pole. Flights between Moscow and Los Angeles, also via Anchorage and operated by IL-62 aircraft, were added in 1994.{{cite news |title=Aeroflot offers LA/Moscow flights |url=https://www.upi.com/Archives/1994/05/17/Aeroflot-offers-LAMoscow-flights/2588769147200/ |work=UPI |date=17 May 1994}} The Anchorage stop was eliminated later in May 1994 when the IL-62 was replaced on this route by the longer-range IL-96.{{cite web |title=Aeroflot History 1990-1999 |url=https://www.aeroflot.ru/xx-en/about/aeroflot_today/aeroflot_history/1990_1999 |publisher=Aeroflot Russian Airlines |access-date=18 December 2023}}

Immediately after the Cold War, a number of direct southern routes had opened up between Europe and Asia over the Black Sea and southern former Soviet republics across Afghanistan, and by the mid-1990s, over China. In Russia's eastern and Arctic regions there were significant problems with lack of English-speaking controllers, lack of radio facilities, poor radar coverage, poor ATC capacity, and a lack of funds. To solve these issues, RACGAT (Russian-American Coordinating Group for Air Traffic) was formed in 1993. By summer 1998, the Russian government worked through these problems and gave permission to open four cross-polar routes, named Polar 1, 2, 3 and 4.Over the Top: Flying the Polar Routes. Avionics Magazine, April 1, 2002. Retrieved 3-07-12. [http://www.aviationtoday.com/av/commercial/Over-the-Top-Flying-the-Polar-Routes_12647.html] {{Webarchive|url=https://web.archive.org/web/20160304190720/http://www.aviationtoday.com/av/commercial/Over-the-Top-Flying-the-Polar-Routes_12647.html |date=2016-03-04 }} Additional routes were opened in subsequent years.

Cathay Pacific Flight 889 from New York John F. Kennedy International Airport, piloted by Captain Paul Horsting on 7 July 1998—the first arrival to the new Hong Kong International Airport at Chek Lap Kok west of Hong Kong—appears to be the first non-stop flight over the Arctic polar region and over Russian airspace by a non-Russian airline. It was the world's first nonstop transpolar flight from New York to Hong Kong, dubbed Polar One. It took 16 hours to complete, and it was and still is one of the longest flights that Cathay Pacific operates.{{cite press release|title=Cathay Pacific's non-stop New York flight 'strengthens Hong Kong's hub'|url=http://www.cathaypacific.com/cpa/en_HK/aboutus/pressroomdetails?refID=aa24e27ed1faa010VgnVCM22000022d21c39____|publisher=Cathay Pacific|date=11 June 2004|access-date=5 July 2009|url-status=dead|archive-url=https://web.archive.org/web/20110927161051/http://www.cathaypacific.com/cpa/en_HK/aboutus/pressroomdetails?refID=aa24e27ed1faa010VgnVCM22000022d21c39____|archive-date=27 September 2011}}

The American Federal Aviation Administration now defines the North Polar area of operations as the area north of 78° north latitude,{{cite web|url=http://www.boeing.com/commercial/aeromagazine/aero_16/polar_story.html|title=Aero 16 - Polar Route Operations|location=Arlington, VA|publisher=Boeing}} which is north of Alaska and most of Siberia.

Aircraft like the Boeing 747-400, 747-8, 777-200ER, 777-200LR, 777-300ER, 777X, 787-8, 787-9, and 787-10, as well as certain variants of the Airbus A330, A340, A350, and A380, with ranges of around {{convert|7000|nmi|km mi nmi|order=out}} or more, are required in order to travel the long distances nonstop between suitable airports.Study Finds Air Route Over North Pole Feasible for Flights to Asia, Matthew L. Wald, New York Times, 10-22-2000. Article retrieved 03-12-09. [https://query.nytimes.com/gst/fullpage.html?res=9B05EFDE1F3CF932A25753C1A9669C8B63&scp=1&sq=polar&st=nyt]

Arctic polar routes are now common on airlines connecting Asian cities to North American cities. Emirates and Qatar Airways fly nonstop from Dubai and Doha to the US West Coast (San Francisco, Seattle, and Los Angeles), coming within a few degrees of latitude of the North Pole.{{cite web|url=http://flightaware.com/live/flight/UAE215 |title=Flightaware website}}{{Cite web |title=QR737 (QTR737) Qatar Airways Flight Tracking and History |url=http://flightaware.com/live/flight/QTR737 |access-date=2022-03-12 |website=FlightAware |language=en}}

In 2022, the Russian invasion of Ukraine has led countries such as the UK{{cite web |title=Ukraine-Russia invasion: Russia launches attack on Ukraine from several fronts |work=BBC News |url=https://www.bbc.co.uk/news/live/world-europe-60454795 |url-status=live |archive-url=https://web.archive.org/web/20220221183326/https://www.bbc.co.uk/news/live/world-europe-60454795 |archive-date=21 February 2022 |access-date=24 February 2022 |publisher=BBC News}} and the US,{{cite web |title=Russia-Ukraine: Biden closes US airspace to Russian flights |url=https://www.aljazeera.com/news/2022/3/2/russia-ukraine-biden-closes-us-airspace-to-russian-flights |website=Al Jazeera |date=2 March 2022 |access-date=7 March 2022}} as well as the entire EU,{{cite news|url=https://www.cbsnews.com/news/ukraine-russia-european-union-airspace-rt-sputnik/|title=EU closes airspace to Russian planes, bans pro-Kremlin media outlets and pledges arms to Ukraine|agency=Associated Press|date=27 February 2022|access-date=7 March 2022|work=CBS News|archive-url=https://web.archive.org/web/20220305215826/https://www.cbsnews.com/news/ukraine-russia-european-union-airspace-rt-sputnik/|archive-date=5 March 2022|url-status=live}} to ban Russian airlines from entering their airspace; these countries received reciprocal bans from operating in Russian airspace. This has led airlines to avoid Russian airspace when flying to certain destinations, including Eastern Asian cities from the US and Europe and vice versa.{{cite news|last=Cox|first=John|title=How will Russia-Ukraine conflict affect air travel? Longer flights, higher fuel costs, fewer planes|url=https://www.usatoday.com/story/travel/airline-news/2022/03/01/how-russia-ukraine-conflict-impacts-air-travel/6978208001/|work=USA Today|publisher=Gannett|date=1 March 2022}}{{cite news|last=Rains|first=Taylor|title=Creative routings to avoid Russian and EU airspace closures are adding up to 4 hours of extra flight time on some plane journeys across the globe|url=https://www.businessinsider.com/airline-routings-add-hours-flight-time-to-avoid-russian-airspace-2022-|work=Business Insider|date=12 March 2022|access-date=12 March 2022}}{{Dead link|date=January 2025 |bot=InternetArchiveBot |fix-attempted=yes }} One instance includes Japan Airlines, whose Heathrow Airport-Haneda Airport route now flies over the Outer Hebrides of Scotland, Iceland, Greenland, Canada, the Arctic Ocean, and Alaska, crossing the International Date Line in the process.{{Cite web |date=2022-03-07 |title=Polar route to Japan is back as Japan Airlines avoids Russian airspace |url=https://www.independent.co.uk/travel/news-and-advice/japan-airlines-polar-route-russia-b2030302.html |access-date=2024-08-19 |website=The Independent |language=en}} (An alternative route from London to Tokyo flies south of Russia and over Turkey, Central Asia, Mongolia and China).{{Cite web |last=Petchenik |first=Ian |date=2022-03-10 |title=Russian roundabout: how flights are avoiding Russian airspace |url=https://www.flightradar24.com/blog/russian-roundabout-how-flights-are-avoiding-russian-airspace/ |access-date=2024-04-02 |website=Flightradar24 Blog |language=en-US}} While this route uses a Boeing 777, which can cover the route without refuelling, its flight time increased by an additional four hours because of the longer new route.{{cite news|last=Calder|first=Simon|title=Polar Route to Japan is Back as Japan Airlines Avoids Russian Airspace|url=https://www.independent.co.uk/travel/news-and-advice/japan-airlines-polar-route-russia-b2030302.html|work=The Independent|date=7 March 2022|access-date=12 March 2022}} The airspace bans also forced cargo airlines to change their course, with some changing their polar routes.{{cite news|last1=Cherney|first1=Mike|last2=Katz|first2=Benjamin|last3=Cameron|first3=Doug|title=Airlines Scramble for Routes Around Russia as Flight Bans Intensify|url=https://www.wsj.com/articles/amid-ukraine-war-airlines-plot-detours-around-russia-as-flight-bans-intensify-11646232786|work=The Wall Street Journal|date=2 March 2022|url-access=subscription}}{{cite news|last=Passy|first=Jacob|title=Russia's war in Ukraine has closed airspace — and disrupted air-cargo transportation|url=https://www.marketwatch.com/story/russias-attack-on-ukraine-has-closed-airspace-and-disrupted-airline-routes-but-its-also-impacted-the-transportation-of-air-cargo-11646416225|work=MarketWatch|date=4 March 2022}}

Few airlines fly between cities having a great circle route over Antarctica. Hypothetically, flights between South Africa and New Zealand, or between either Western Australia or Western Southeast Asia and southern South America, would overfly Antarctica, but no airline currently operates such flights.

Flights between Australia and South America and between Australia and South Africa pass near the Antarctic coastline. Depending on the winds, the Qantas flight QFA63 from Sydney to Johannesburg{{spaced endash}}O. R. Tambo, or the return flight QFA64, sometimes flies over the Antarctic Circle to 71° latitude as well and allowing views of the ice sheet.{{Better source needed|reason=The link has no information this flight at 71° latitude. |date=September 2019}} Qantas QFA27 and QFA28 and LATAM LA809 and LA810 fly nonstop between Sydney and Santiago de Chile, the most southerly polar route. Depending on winds, this flight may reach 70° south latitude. From July 2012[https://www.lavoz.com.ar/ciudadanos/aerolineas-argentinas-unira-buenos-aires-sydney-sin-escalas Aerolíneas Argentinas unirá Buenos Aires-Sydney sin escalas] until 2014, Aerolíneas Argentinas flew nonstop between Sydney and Buenos Aires.{{cite web|url=http://flightaware.com/live/flight/ARG1180 |title=Flightaware website}}{{Better source needed|reason=The link is to a flight which no longer operates and only shows a great circle route, not actual flight path.|date=September 2014}} Previously, Qantas also operated QFA17 and QFA18 between Sydney and Buenos Aires. Nowadays, LATAM operates LAN804 and LAN805 between Melbourne, Australia, and Santiago, Chile, and Air New Zealand, until 2020, operated ANZ30 and ANZ31 between Auckland and Buenos Aires all with similarly south-running routes.{{facts|date=October 2022}}

The polar route across the remote southern Pacific Ocean between South America and Oceania was pioneered by LAN Chile (now LATAM), with a special flight from Santiago to Sydney operated with a Boeing 707 in 1974, with a stop in Punta Arenas (Chile). Commercial flights began with Aerolíneas Argentinas, with service from Buenos Aires via Rio Gallegos to Auckland in the 1980s flown with a Boeing 747-200 aircraft. Aerolíneas Argentinas later extended its service to Sydney via Auckland and Rio Gallegos with return flights to Buenos Aires not making a stop in Rio Gallegos,{{Cite web| title=Aerolineas Argentinas - International Services | url=https://www.timetableimages.com/ttimages/ar/ar89/ar8901-2.jpg | archive-url=https://web.archive.org/web/20121008235113/http://www.timetableimages.com/ttimages/ar/ar89/ar8901-2.jpg | archive-date=2012-10-08}} but then ended its flights to New Zealand and Australia in 2014.

Previously, because of ETOPS limitations on twin-engined aircraft — the maximum distance the aircraft can operate from an airport for emergency landings — only four-engined aircraft such as the Boeing 747, Airbus A340, and Airbus A380 could operate routes near Antarctica. Twin-engined aircraft had to fly further north, closer to potential diversion airports; for example, when Virgin Australia operated their VA 15 and VA 16 flights between Melbourne and Johannesburg on twin-engined Boeing 777 aircraft with a 180-minute ETOPS rating, the flight was two hours longer than a Qantas flight from Sydney to Johannesburg.{{cite news|last1=Freed|first1=Jamie|title=Virgin Australia brings back direct flights to Johannesburg through South African Airways codeshare|url=http://www.bordermail.com.au/story/2596703/virgin-australia-brings-back-direct-flights-to-johannesburg-through-south-african-airways-codeshare/|access-date=21 March 2017|work=The Border Mail|date=1 October 2014}} In 2015, government regulators approved Air New Zealand's twin-engined Boeing 777-200ER aircraft for a 330-minute ETOPS rating (i.e. its 777 aircraft can fly a maximum 330 minutes away from the nearest diversion airport), an increase from its previous 240-minute ETOPS rating, to operate their new route between Auckland and Buenos Aires-Ezeiza which ended in 2020.{{cite news|last1=Carey|first1=Bill|title=Air New Zealand 777 Makes First 330-Minute ETOPS Flight|url=http://www.ainonline.com/aviation-news/air-transport/2015-12-02/air-new-zealand-777-makes-first-330-minute-etops-flight|access-date=21 March 2017|work=AINonline|publisher=The Convention News Company, Inc.|date=2 December 2015}} LATAM Airlines began their LAN800 and LAN801 nonstop flights between Santiago de Chile and Sydney via Auckland in April 2015 with twin-engined Boeing 787 aircraft with a 330-minute ETOPS rating.{{cite news|last1=Leaman|first1=Aaron|title=Flight test: Auckland to Santiago on LATAM's Boeing 787-9|url=http://www.stuff.co.nz/travel/news/82400804/flight-test-auckland-to-santiago-on-latams-boeing-7879|access-date=21 March 2017|work=Stuff|date=31 July 2016}}{{cite news|last1=Clark|first1=Peter|title=PICTURE: LAN avails of 787 ETOPS certification|url=https://www.flightglobal.com/news/articles/picture-lan-avails-of-787-etops-certification-411442/|access-date=21 March 2017|work=Flight Global|date=22 April 2015}} LATAM has announced a nonstop flight between Santiago de Chile and Melbourne (LAN804/LAN805) to begin in October 2017.{{cite news|title=LATAM to serve Melbourne-Santiago nonstop from October 2017|url=http://australianaviation.com.au/2016/12/latam-to-serve-melbourne-santiago-nonstop-from-october-2017/|access-date=21 March 2017|work=Australian Aviation|date=5 December 2016|archive-url=https://web.archive.org/web/20170321170847/http://australianaviation.com.au/2016/12/latam-to-serve-melbourne-santiago-nonstop-from-october-2017/|archive-date=21 March 2017|url-status=dead}}{{cite news|last1=Flynn|first1=David|title=LATAM to fly Melbourne-Santiago from October 2017|url=https://www.ausbt.com.au/latam-to-fly-melbourne-santiago|access-date=21 March 2017|work=Australian Business Traveller|date=5 December 2016}} In late 2019, LATAM began direct flights between Santiago and Sydney (LA802/LAN803) competing with the existing Qantas (QFA27/QFA28) flights on the same route.

The southernmost flight route with plausible airports would be between Buenos Aires and Perth.{{cite web |url=http://www.greatcirclemapper.net/en/great-circle-mapper.html?route=SAEZ-YPPH&aircraft=73&speed= |title=Great Circle Mapper: EZE-PER |website=Great Circle Mapper }} With a 175° (S) heading, the route's great circle exceeds 85° S and would be within {{convert|500|km}} of the South Pole. Currently, no commercial airline operates this {{convert|6800|nmi|km mi nmi|adj=on|order=out}} route. However, in February 2018, it was stated that Norwegian Air Argentina is considering this "less than 15 hours" trans-polar flight between South America and Southeast Asia, with a stop-over in Perth en route to Singapore.{{cite web|url=https://thewest.com.au/travel/air-aviation/perth-stopover-on-world-first-flight-linking-south-america-and-asia-to-boost-wa-tourism-ng-b88751880z|title=World-first South American flight to boost WA tourism|date=25 February 2018|website=The West Australian}} They will not fly over the South Pole, but around Antarctica taking advantage of the strong winds which circle that continent in an easterly direction. Hence, the "westbound" flight from Buenos Aires would actually travel south-east south of Cape Town, over the southern Indian Ocean and on to Perth, while the true "eastbound" flight would also head south-east south of Tasmania and New Zealand, over the South Pacific and on to South America. If this route becomes operational, a Buenos Aires{{spaced endash}}Singapore return flight would possibly be the fastest circumnavigation available with commercial airliners, although Perth{{spaced endash}}Buenos Aires return would be faster but without passing the Equator.{{facts|date=October 2022}}

The FAA's policy letter Guidance for Polar Operations (March 5, 2001) outlines a number of special requirements for polar flight, which includes two cold-weather suits, special communication capability, designation of Arctic diversion airports and firm recovery plans for stranded passengers, and fuel freeze strategy and monitoring requirements.

Jet fuel freeze temperatures range between {{convert|-40|and|-50|C|abbr=on}}. These temperatures are frequently encountered at cruise altitude throughout the world with no effect since the fuel retains heat from lower elevations, but the intense cold and extended duration of polar flights may cause fuel temperature to approach its freezing point. Jet A grade with a maximum freeze point of {{convert|-40|C|abbr=on}} is used in the U.S., while Jet A1 grade with a maximum freeze point of {{convert|-47|C|abbr=on}} is used elsewhere.[ASTM specification D1655] Modern long-distance airliners are equipped to alert flight crew when fuel temperatures reach {{convert|3|C-change|abbr=on}} above these levels. The crew must then change altitude, though in some cases due to the low stratosphere over polar regions and its inversion properties the air may actually be somewhat warmer at higher altitudes.

The alerts are typically set at {{convert|3|C-change|abbr=on}} above the specified maximum freeze point. This provides a {{convert|3|C-change|abbr=on}} safety margin from the solidification temperature. However, fuels produced at the refineries are often better than the spec values; for example, it is not uncommon to find Jet A fuels that have measured freeze point better (colder) than the specified maximum of {{convert|-40|C|abbr=on}}. In that way, the safety margin is even larger than {{convert|3|C-change|abbr=on}}. On the other hand, the temperature probe that delivers fuel temperature information to the flight deck is not located in the coldest part of the fuel tanks. The difference between the recorded and the coldest fuel temperature varies depending on a variety of factors, especially the circulation of fuel in the tanks and duration of cold soak. It is, therefore, prudent to have a safety margin.{{facts|date=October 2022}}

For polar flights, FAA allows,{{Citation |last=Federal Aviation Administration, US Department of Transportation |title=Extended Operations (ETOPS and Polar Operations) |date=June 13, 2008 |url=https://www.faa.gov/documentLibrary/media/Advisory_Circular/120-42B.pdf |archive-url=https://web.archive.org/web/20130616090849/http://www.faa.gov/documentLibrary/media/Advisory_Circular/120-42B.pdf |id=AC 120-42B |archive-date=June 16, 2013}} under certain conditions, the measured freeze point be used instead of assuming the spec value in ASTM D1655. This gives the airlines more flexibility in flight planning.

{{Portal|Geography}}

• Longest flights
• Great circle
• Antarctica

{{reflist|30em}}

• [https://web.archive.org/web/20020329000146/http://www.racgat.com/ RACGAT website] – archived in 2003
• [http://www.flightradar24.com/blog/flight-paths-and-great-circles-or-why-you-flew-over-greenland/ Flightradar24 blog page – Why you flew over Greenland]

{{Arctic topics}}

Category:Air traffic control

Category:Air navigation

Category:Polar regions of the Earth

Category:Airline routes