(CNN) — If you're already finding long-haul flights to be at the limits of human endurance, then assume the brace position -- some of the world's longest flying legs are about to get even longer.
With aircraft design becoming more fuel-efficient -- and time-starved passengers more demanding -- the race is on to create commercial long-haul flights that span ever greater distances.
Qantas has confirmed that it will be launching a London-to-Perth leg when it receives its first Boeing 787 -- also known as the Dreamliner.
The 14,498-kilometer (9,008 miles) service, due to begin in March 2018, will be the first regular passenger flight to directly link Australia with Europe.
"When Qantas created the Kangaroo Route to London in 1947, it took four days and nine stops," said Qantas Group CEO Alan Joyce in a statement.
"Now it will take just 17 hours from Perth non-stop."
In the meantime, other airlines are jostling for position to offer flights that cover the greatest distance in the shortest possible time.
But even at full stretch, the world's longest routes are already nudging 17 hours, making the world's great "red-eye" flights even more fatiguing.
Following on from our feature on the world's shortest airline routes, CNN is reaching for the melatonin, pulling down the eyeshades and dragging on the compression socks to bring you the world's longest air routes.
World's longest air route
There is strong competition for this spot.
The Gulf carriers Emirates and Qatar Airways are locked in a struggle for their Dubai-Auckland and Doha-Auckland ultra-long-haul flights.
In March, Emirates claimed the title of the world's longest commercial flight, completing the 14,200 kilometers (8,824 miles) to the New Zealand city.
Qatar Airways announced plans to launch flights from Doha to Auckland later this year or early in 2017. This leg will just pip Emirates at 14,539 kilometers (9,034 miles).
Longest regular nonstop route by time
Flying with Emirates from Dubai to Panama City will take over 17 hours, making it the longest nonstop journey in the world.
Dubai (United Arab Emirates) to Auckland (New Zealand)
Airline: Emirates. (DXB-AKL). Distance: 8,824 miles (14,200 kilometers)
In terms of time alone, Emirates takes pole position with its Auckland flights.
Flown daily by a Boeing 777-200LR configured for 266 passengers, it takes 16 hours on the outbound leg (it completed its maiden voyage in 16 hours and 24 minutes) and 17 hours and 15 minutes on the return flight.
As of October 31, the airline began plying the route with the Airbus A380, the longest route yet to be served by the giant airliner.
Longest route in terms of distance
Delhi (India) to San Francisco (United States)
Airline: Air India. (DEL-SFO). Distance: 9,408 miles (15,140 kilometers)
Air India now flies to San Francisco via the Pacific rather than via the usual polar route -- a move that saves valuable fuel.
The new route for the Boeing 777-200LR means Air India can take advantage of the high-altitude jet stream, giving it speed-boosting tailwinds all the way to San Francisco.
The return leg then takes advantage of the polar route.
While the long-haul flight clocks up 1,000 more miles, it takes two hours off the journey at just over 15 hours.
Longest international flight in near future
Doha (Qatar) to Auckland (New Zealand)
Airline: Qatar Airways. (DOH-AKL). Distance: 9,032 miles (14,535 kilometers). Starts on February 5, 2017
As Doha is slightly west of Dubai, the moment Qatar Airways launches its own nonstop flight to Auckland it will be able to claim first place in the ranking (also in terms of time).
This flight, which is expected to begin operation in February 2017, will also be plied by the reliable Boeing 777-200LR.
Longest nonstop domestic flight
La Réunion islanders bid farewell to an Air France plane.
Paris to La Réunion (France)
Airlines: Air Austral, XL Airways. (CDG-RUN). Distance: 5,809 miles (9,348 kilometers)
Airlines: Air France, Corsair, French Blue (planned). (ORY-RUN). Distance: 5,802 miles (9,337 kilometers)
Believe it or not, it is neither Russia, nor Canada, nor the US, but France that can lay claim to the longest nonstop domestic flight.
This trick of geography and history, which means French overseas territories (or département d'outre-mer) have the same status as their metropolitian equivalents in mainland France, makes the long-haul flight from Paris to the island of La Réunion, in the Southern Indian Ocean, the world's longest domestic flight.
There are no shortage of airlines linking Roland Garros airport (named after the WWI aviator and native of the island who also gives his name to the French Open tennis grand slam) to both Paris international airports, Charles de Gaulle and Orly.
Longest domestic flight over continuous territory
Moscow Vnukovo to Petropavlovsk Kamchatsky (Russia)
Airline: Rossiya Airlines. (VKO-PKC). Distance: 4,227 miles (6,803 kilometers)
Moscow Sheremetyevo to Petropavlovsk Kamchatsky (Russia)
Airline: Aeroflot. (SVO-PKC). Distance: 4,203 miles (6,764 kilometers)
Russia is such a large land mass that its domestic flights can put a New York to London transatlantic hop in the shade.
Aeroflot and its subsidiary, Rossiya, operate regular flights between Moscow and Petropavlovsk-Kamchatsky, the gateway to a mountainous peninsula on Russia's Pacific coast.
Once famous as a submarine base, Kamchatka is now best known for its volcanoes.
Longest domestic flight with a stop
Thanks to its distant overseas territories, France boasts some of the world's longest domestic flights.
Paris CDG to Papeete (France), via Los Angeles (United States)
Airline: Air France. (CDG-LAX-PPT). Distance: 5,669 + 4,095 = 9,765 miles (15,715 kilometers)
Once again, France's overseas territories do the trick.
Although French Polynesia is out of range for any Paris-based airliner, a convenient refueling stop at Los Angeles International airport makes it possible for Air France's Boeing 777s to reach Tahiti from Europe in less than 24 hours.
Honolulu (United States) to Majuro (Marshall Islands) to Kwajalein (Marshall Islands) to Pohnpei (Micronesia) to Chuuk (Micronesia) to Guam (United States)
Airline: United Airlines. It takes more than 14 hours.
Although not strictly a non-stop flight, United Airlines Flight 154 and its return counterpart, UA 155, deserve a mention here.
This flight links Honolulu to Guam, but what makes it special is that, rather than doing so directly, it hops from atoll to atoll across the immensity of the Pacific Ocean, making stops at Majuro, Kwajalein (both in the Marshall Islands), Pohnpei and Chuuk (in the Federated States of Micronesia).
It takes more than 14 hours to complete the itinerary and the aircraft, a narrow-bodied Boeing 737-800, carries an extra crew on-board.
In this way, UA154 preserves the legacy of what was one of the legendary air routes of the pre-war period, when Pan Am's flying boats, the famous China Clipper among them, flew between Alameda (California) and Manila by way of Honolulu, Midway Island, Wake Island and Guam.