A Delta Air Lines DC-9 taxis on the tarmac on Monday at Minneapolis-Saint Paul International Airport before its final scheduled flight.
CNN  — 

Nearly half a century after it became the first U.S. airline to fly twin-engine DC-9s, Delta Air Lines retired the last of those venerable airliners from its commercial service Monday.

The final round trip bore the designation Delta 1965 – the first year the model entered service – on its way from Atlanta to Minneapolis, and Delta 2014 on the return flight. Delta was the last major U.S. carrier to fly the DC-9, the company said.

Delta had retired its original DC-9s in 1993, but acquired others in its merger with Northwest Airlines in 2008, the company said.

McDonnell-Douglas, which merged with Boeing in 1997, built the last of the T-tail aircraft in 1982. The DC-9 has been replaced by similar-looking successor models such as the MD-88 and Boeing 717 since then.

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