In the long-running battle for the most delivered aircraft, is Boeing or Airbus winning? Boeing obviously launched the 737 long before Airbus launched the A320. This early start served Boeing well for many years, but Airbus has caught up recently. The A320 has moved ahead in sales - but the 737 retains the lead for aircraft delivered.
The Boeing 737
Boeing launched the narrowbody 737 in 1967. At the time, its twin engines marked a significant shift in jets. Its previous aircraft, the 707 and the 727 were four and three-engine aircraft. Market attention was shifting to a more economical two-engine possibility.
The 737 differed from its competition at the time by placing the two engines under the wings rather than on the rear of the fuselage. This allowed for a wider cabin and easier engine access for maintenance and has since become the standard.
The 737-100 first flew with Lufthansa in February 1968. However, only 30 737-100 aircraft were ever delivered, as it was soon improved by the 737-200. Sales of the new variant started slowly, but Boeing went on to sell 1095 aircraft, and its success in twin narrowbodies was underway.
The 737, of course, remains well in production today, over 50 years later. It has evolved through several variants, taking advantage of new technology and changes in airline expectations. The 737-800 has been the most sold of all variants, with an impressive 4,991 orders. This is due to its combination of range and capacity, not the largest of either, but a very versatile option for many airlines.
Orders have slowed and dropped back in some cases recently. Both the slowdown in global aviation and the issues with the 737 MAX have hit the type hard. It remains though the most delivered aircraft.
The Airbus A320
Airbus launched the A320 to compete with the Boeing 737. Airbus was formed to take on Boeing and other manufacturers and had done so already with the A300 and A310. The A320 entered service in April 1988 with Air France - over 20 years after the 737. It has caught up impressively in sales and deliveries.
Like Boeing and the 737, Airbus has continued to make improvements to the A320 through a series of new variants. Most significantly, the re-engined A320neo was launched in 2010. This prompted the development of Boeing's 737 MAX series.
Airbus moved ahead of Boeing for total orders in late 2019. Boeing's recent issues with the 737 MAX have undoubtedly given Airbus a boost, As has Airbus' ambitious plans with the A321LR and A321XLR versions of the A321neo. The A321XLR is a potential game-changer in aviation. It will see narrowbodies operating on longer routes than ever, bringing airlines many new possibilities, particularly if demand remains subdued.
Numbers as of October 2021
It's fair to say that the race is close. Boeing has always been ahead in aircraft delivered and remains so in 2021. The A320 is catching up, though - impressive given it has had around 20 years less in production.
According to data from Boeing, 10,617 Boeing 737 aircraft have been delivered to date. The milestone 10,000th aircraft went to Southwest Airlines in March 2018.
Airbus has (based on data as of the end of August 2021) delivered 10,004 A320s. Its aircraft registered MSN 10,000 went to Lebanese airline MEA in October 2020.
Looking at outstanding orders shows the strong position Airbus is in. Boeing lists 4,076 unfilled orders for the 737. Airbus has 5,696 A320s remaining on order.
Where things go next depends to a large extent on Boeing's next move in aircraft development. For a long time, we were expecting a new launch with the New Mid-sized Airplane (NMA), often dubbed the 797. Boeing dropped plans for this in 2020. This was due not only to issues with the 737 MAX and budgets but also as a response to Airbus's launch of the A321XLR.
Boeing urgently needs something to compete in that market. Sticking with the 737 and further updates is one option, but there are several more. A re-engining of the 757 is possible, as is a new widebody option based on the 767 or 787.
Don't forget the DC-3
While discussing most built aircraft, we have to give the Douglas DC-3 a mention. This aircraft launched in 1936 and remained in production until only 1942.
It has out-sold both the 737 and A320 - with 16,079 built. Most of these were for military use however - only 607 were for civilian airline use. It was operated by many airlines, including American, United, TWA, Eastern, and Delta. It was certainly a massive success for Douglas and something we won't see Boeing or Airbus beating for some time yet.
Both the Boeing 737 and Airbus A320 have been great success stories. Both manufacturers have continued to develop and adapt them, keeping them in production for decades. Both have now passed the 10,000 aircraft delivered mark, but which do you think will make the next milestone? Feel free to discuss this in the comments.