The all-new Boeing 747-8 Intercontinental, which the aviation giant formally unveiled last month, is expected to take its first flight this Sunday, March 20.

Boeing announced today that its all-new 747-8 Intercontinental, the longest passenger plane in its history, is expected to take its first flight on Sunday.

Earlier in the day, the aviation giant said that the plane--which it unveiled in a huge ceremony just last month--had passed what is called final gauntlet testing, which "simulates flight conditions to test systems and ensure flight readiness," Boeing said in a release, adding that as part of the testing process, its test pilots "put the airplane through its paces."

Over the next few days, then, the plane will be subjected to "final flight readiness reviews, receipt of documentation from the U.S. Federal Aviation Administration and taxi testing," Boeing said. If all goes well, and if the weather permits, the plane should take to the sky sometime after 10 a.m. on Sunday.

Should that happen, Boeing will have gotten the new plane from unveiling to first flight in just over a month, a great deal faster than it did with its other major new commercial airplane program, the 787 Dreamliner, which was unveiled on July 8, 2007--07/08/07--and didn't take its first flight until December 15, 2009. The cargo version of the 747-8 made its initial flight on February 8, 2010.

Boeing bills the new 747-8 as the next-generation of its most iconic plane and as the most fuel- and cost-efficient passenger aircraft it has produced. One major highlight is its new wing design. Created using "the latest in computational fluid dynamics validated in the world's most sophisticated wind tunnels," Boeing said, the wings offer improved aerodynamics and larger fuel capacity while also allowing the plane to be as fast as, or faster than, any other passenger aircraft in the world.

The new wing design sports "fly-by-wire spoilers and ailerons that make it possible to incorporate a flight control feature known as a maneuver load-alleviation system," Boeing said. "Pioneered on the 787 Dreamliner, it changes the lift distribution over the wing during non-normal flight conditions, reducing the load on its outboard portion." This means a smaller wing structure that is 1,400 pounds lighter than that used on the 747-current-generation 747-400, while not compromising structural integrity.

Boeing is aggressively touting the plane's economic and green credentials: it is the only passenger plane in the 400- to 500-seat market, its four General Electric GEnx 2B engines use 16 percent less fuel per seat than those on the 747-400 and 11 percent less than does Airbus' giant A380.

This is all possible, Boeing said, because of its use of advanced materials in the construction and design of the plane, as well as its use of the GEnx engines, and the form factor and materials of its wings. Most of the plane is made from new aluminum alloys, while it also incorporates graphite composites in the rudder, spoilers, flaps, and other areas.

As designed, the 747-8 Intercontinental will carry 467 passengers in a three-class configuration, and has a range of 8,000 nautical miles. The freighter version of the 747-8 can fly up to 4,390 nautical miles. The Intercontinental has a wing span of 224 feet, 7 inches, and is 250 feet, 2 inches long. Its tail towers to 63 feet, 6 inches high. And its four GEnx-2B67 engines produce 66,500 pounds of thrust. The passenger plane's top cruising speed is Mach 0.86, while the freighter can fly at Mach 0.845.

Please stay tuned for CNET's coverage of the 747-8 Intercontinental's first flight this Sunday, weather permitting.