In an era where it takes years — often many years — to bring a warplane from drawing board to flight line, Tuesday's first flight of a new Boeing-Saab training jet in St. Louis shows that defense firms can, on occasion, build a complex weapon quickly.

In one year, the firms went from certifying the design of its plane to flying it — light speed for the defense industry.

“We don’t do that very often at The Boeing Company,” said Ted Torgerson, the project’s program manager. “I don’t want to say it’s not been done, but for a manned aircraft to go through a complete and production-ready design — that is as fast and as efficient as we’ve ever been through it.”

The new jet took off from Lambert-St. Louis International Airport, home of Boeing's military aircraft division, where the company builds F-15 and F/A-18 fighter jets. During the 55-minute flight, Boeing test pilot Steven Schmidt flew the plane to nearly 11,000 feet. The company plans to fly the jet for the second time “in the next few days,” Torgerson said.

“We haven’t done anything like this in terms for a production aircraft,” Eddy De la Motte, Saab deputy program manager, said when asked about the rapid timeline. “This really proves the ability that we bring to the table here jointly.”

In the three years since the American and Swedish companies signed a deal to work together on Dec. 5, 2013, the duo has created two new aircraft. Some parts were built in Sweden, but assembled in St. Louis. Boeing has not said where it would build the plane if it wins the U.S. Air Force competition to replace the 1960s-era T-38 Talon.

The Boeing-Saab plane is not the only new jet in the Air Force’s T-X contest. Northrop Grumman has built and flown a new plane quickly itself, although company leaders have chosen not to talk about it. Last week, Sierra Nevada Corp. and Turkish Aerospace Industries told Aviation Week that they would offer a bid in the competition. The other jets in the competition are the T-50, built by Lockheed Martin and South Korea’s KAI, and the T-100, made by Raytheon and Italy’s Leonardo. The Air Force is expected to choose a winner in 2017.