Airbus said A320 family aircraft recently passed the 50-million-flight milestone and have carried 5 billion passengers since entering commercial service in 1988.

“One of our A320 family aircraft takes off every six seconds somewhere around the world,” COO-Customers John Leahy noted, adding that the manufacturer is “investing at least €100 million [$122.7 million] a year in the A320 family” to improve its efficiency and extend the program’s life “for decades to come.”

Incredibly, the then-fledgling A320 was the stumbling block for a failed merger attempt between Airbus and McDonnell Douglas in 1989, with the US manufacturer insisting that any new single-aisle aircraft resulting from the merger be based on the MD-80/-90 line. Airbus dismissed the notion, saying that the MD-80/-90 was “old technology.”

It had delivered about 70 A320s of the several hundred on order at the time and wanted McDonnell Douglas to build A320s for US airlines. Airbus has now sold 6,500 A320s in just over 25 years, almost twice the number of all the commercial jets built at McDonnell Douglas’s Long Beach factory from 1956 to 2006.

The first member of the A320 family, the A320, was launched in March 1984, first flew on Feb. 22, 1987, and was first delivered in 1988. The aircraft now can be seen in the colors of some 250 different airlines and 60 other customers and there are 10 operators with more than 100 in their fleets.