Boeing Co's 747-8 Intercontinental, the new passenger version of its legendary jumbo jet, completed its maiden flight without a hitch on Sunday, marking a key milestone for the aircraft model more closely associated with Boeing than any other plane.

The behemoth began its first test flight from Boeing's Paine Field north of Seattle into clear blue skies at 9:58 a.m. local time. The take-off, witnessed by thousands of Boeing employees and aviation enthusiasts, occurred almost 42 years after the first flight of the original 747, which later became one of the most recognized planes in the world.

After almost four and half hours in the air, the red and white plane landed safely at Boeing Field just south of central Seattle.

The 747-8 Intercontinental will seat 467 passengers, 51 more than the current version of the 747. It promises to burn less fuel and offer more passenger comforts. The plane also boasts new wings, a new tail, state-of-the-art engines and a new cockpit.

The 747 was the world's largest airplane until 2005, when Airbus unveiled its 525-seat A380.

Boeing has taken orders for 33 747-8 passenger planes, according to the company website on Friday. The plane lists at $317.5 million.

Germany's Lufthansa has ordered 20 of the planes, and is set to be the first airline to bring the new jumbo into service early next year.

Production of the new 747 has been delayed as has the mid-sized 787 Dreamliner, a carbon-composite plane, which represents a bigger leap in technology than the revamped 747-8.

The stronger-selling freighter version of the 747 has already flown and is due to be delivered in mid-2011 -- 18 months later than first planned. Boeing has sold more than 70 747-8 freighters.

(Reporting by Bill Rigby in Seattle and Kyle Peterson in Chicago; Editing by Diane Craft)