Everyone knows that the world’s longest flight by great circle distance is from New York to Singapore. At over 19 hours, 8,288 NM, and 15,349 KM, this route connects the largest and most important city in the Americas to one of Asia’s strongest financial centers. The flight is so long that it requires a special version of the Airbus A350-900 (the A350-900ULR) with extra fuel capacity and only 161 seats in a configuration that only features business class and premium class.
Except, this is the world’s longest nonstop flight. There are, however, some one-stop routes that carry the same flight number (also known as a fifth-freedom route) that are longer, the longest of which is Air China’s route from Beijing to São Paulo via Madrid. China Eastern Airlines, however, has announced a new route from Shanghai to Buenos Aires with a stopover in Auckland. This flight is blocked at 29 hours returning to Shanghai, flying a combined total of 10,626 NM (19,620 KM), making it the world’s longest direct flight.
What Type Of Route Is This?
This is known as a “fifth freedom route” because it uses the fifth of the “five freedoms of aviation”. These are a set of regulations permitting commercial aircraft to fly through foreign airspace. The first permits planes to overfly other nations, while the second allows for technical stops without taking on or disembarking passengers. The third and fourth freedoms allow airlines to fly to and from a foreign country while originating in their home nation.
The fifth freedom is similar to the second freedom in that both allow airlines to perform a stopover in a foreign nation as part of a single flight. The fifth freedom, however, allows airlines to pick up and disembark passengers in the stopover city. Air China, for instance, sells tickets between Beijing and São Paulo, Beijing and Madrid, as well as between Madrid and São Paolo. Both segments operate using the same flight number.
While the term is “five freedoms”, there are actually nine freedoms of aviation. The first five freedoms are typically granted universally, whereas the remaining four are less common. These include the right to fly from one foreign country to another with a stop in an airline’s home country, the right to fly between two foreign nations, the right to operate domestic routes in a foreign country with a continuation to an airline’s home nation, and the right to fly domestically without a continuation.
Examining China Eastern’s New Service
China Eastern MU745 and MU746 are the flight numbers for China Eastern’s new service from Shanghai to Buenos Aires via Auckland. The flight is scheduled for 25 hours 55 minutes, flying from Shanghai to Buenos Aires and 29 hours on the return. The aircraft will stay on the ground in Auckland for two hours and 25 minutes flying eastbound and two hours flying westbound. The returning flight from Buenos Aires will be the world’s longest flight by duration at 29 hours.
China Eastern will use the Boeing 777-300ER on this route. These are the carrier’s largest, most premium aircraft. Data from aeroLOPA shows that China Eastern configures this airplane with 316 seats, made up of six first-class seats, 52 business-class seats, and 258 economy seats. The first class seats are configured four-abreast in row two, while row one features a large closet and a walking area in the center of the cabin. Business class is configured four-abreast, while economy is configured 10-abreast.
|
Cabin |
Number Of Seats |
Seat Model |
|---|---|---|
|
First Class |
6 |
Custom |
|
Business Class |
52 |
Safran Cirrus II |
|
Economy |
258 |
Safran Z300 |
The service will launch on December 4, 2025, and will operate twice weekly. MU745 will depart
Shanghai Pudong International Airport at 02:00 and arrive in Buenos Aires Ezeiza International Airport at 16:55, while MU746 will depart at 02:00 and arrive in Shanghai at 18:00 the next day. The flight from Shanghai to Auckland will take 11 hours 30 minutes, while the flight time to Buenos Aires is blocked at 12 hours. The returning segments will take 14 hours 40 minutes and 12 hours 20 minutes.
Why The Stopover Isn’t A Big Deal
China Eastern is the nation’s second-largest airline (after China Southern). It has a fleet of 664 aircraft and, with this new flight, will have service to all six inhabited continents. This is, however, the carrier’s first route to South America, which currently has no nonstop flights to East Asia. There also exists Air China’s similar one-stop service from Beijing to São Paulo that routes via Madrid, the other notable one-stop flight between the two continents.
Part of the reason why this is the case is the distance. Flying nonstop from Shanghai to Buenos Aires, the flight is 10,580 NM (19,595 KM) long, while a nonstop route from Beijing to São Paulo would span 9,491 NM (17,577 KM). This is too far for any airliner to fly nonstop with an economical payload, and while the stopovers add time, they don’t actually add a significant amount of distance. In other words, the stopover points are more or less on the way.
Fifth-freedom routes are often used to connect two cities that have significant demand but are too far to fly nonstop. Qantas serves New York with a stopover in Auckland, while Singapore Airlines still maintains its one-stop service to New York-JFK despite also operating a nonstop flight, as the nonstop uses A350s configured with 161 seats consisting of only business class and economy. As such, this route isn’t that unusual for featuring a stopover.
Where Is The Demand Coming From For This Route
Even when counting one-stop routes, air service between East Asia and South America is minimal. Part of this is the distance, as one-stop routes can be expensive to operate, and the immense duration can scare off potential travelers. However, demand between these two regions is also relatively low. Argentina has a relatively small Chinese population, and business links between the two cities are low.
However, there is a strong demand between China and New Zealand. China Eastern already operates a daily flight between Shanghai and Auckland using the 777-300ER, and Air New Zealand flies a daily Boeing 787 between the two cities. Adding another 777-300ER for two days out of the week, while a major bump in capacity, is not an unreasonable proposition. Furthermore, air links between South America and Oceania are also growing.
|
Airline |
Origin |
Destination |
Aircraft |
|---|---|---|---|
|
China Eastern |
Auckland |
Buenos Aires |
Boeing 777-300ER |
|
LATAM |
Santiago |
Auckland |
Boeing 787-9 |
|
LATAM |
Santiago |
Melbourne |
Boeing 787-9 |
|
LATAM |
Santiago |
Sydney |
Boeing 787-9 |
|
Qantas |
Sydney |
Santiago |
Boeing 787-9 |
Qantas currently flies from Sydney to Santiago four times a week with its Boeing 787, competing against LATAM, which also flies from Santiago to Auckland. This will be Buenos Aires’ first route to Oceania, but the region as a whole has been seeing an increase in service to Australia and New Zealand. As such, while travel demand between Argentina and China is low, the carrier is tapping into strong local demand from China to New Zealand and growing demand from New Zealand to Argentina.
China Eastern Is Government-Owned
Like all the nation’s largest carriers, China Eastern is majority-owned by the Chinese government. As such, while there is merit to the route when considering the travel segments that it taps into, the airline is not solely looking at whether the route will turn a profit. Rather than just load factors, yield, cost per available seat mile, revenue per available seat mile, or any number of quantitative performance data, the airline will also look at other metrics to determine its success. In other words, the route will be successful if the Chinese government deems the route a success.
China has been developing close political and economic ties with several South American countries. China and Argentina continue to strengthen their ties, with several economic partnerships and although the nation declined to join BRICS, Argentina continues to maintain close relations with China. As such, it’s highly likely that there is a political aspect to it, especially when you consider that the Chinese government maintains strong control over its airlines.
To be clear, there is demand for this route on both of its sectors, and the increasing economic cooperation also increases demand for the entire route. However, there is a political benefit in having one of your nation’s largest airlines launch a route to the capital of a nation with which you want to strengthen ties. As such, while China Eastern will sell many tickets, the political implications are almost certainly a factor in the launch of this route.
Rundown Of The World’s Newest Longest Flight
A route from Shanghai to Auckland already exists, with two airlines currently serving it. A flight from Auckland to Buenos Aires, while new, has some merit as air travel between Oceania and South America increases. Combining the two, while unusual, is not a crazy idea, and it’s telling that China Eastern intends to use its largest, most premium aircraft on this new route.
However, the airline’s government-owned status means that the Chinese government does exert influence on the carrier’s decisions. The country is looking to get closer to Argentina and other South American countries, and the nation also has links to Brazil via Air China’s one-stop route, also a government-owned airline.

