The newest version of Boeing’s 747, the 747-8 Freighter, has passed its initial airworthiness testing, the company said today.

Passing those basic tests allows Boeing to carry testing engineers aboard the plane and to bring the second and third test aircraft into the testing regimen.

“The airplane is performing as expected in the initial stages of flight test,” said Mo Yahyavi, vice president and general manager of the 747 program.

Now that the first test aircraft has demonstrated its basic flight performance, Boeing will expand the flight test program to test the edges of the plane’s flight envelope.

The newest version of the 747 includes a new wing, new generation engines, improved electronics and an upgraded interior. The plane is stretched to carry more cargo and passengers than its predecessor, the 747-400, and it operating costs per passenger are expected to be as much as 15 percent less.

Boeing will initially base the 747-8 testing in Moses Lake and later move the testing base to Southern California.

Airlines, cargo companies and VIPS have ordered 108 of the aircraft. The first delivery is planned for the fourth quarter of this year after the plane earns its flight certification from the Federal Aviation Administration.