When Newton thought up the three laws of motion, one wonders if he envisioned anything like these three airplanes currently parked together at Washington Dulles International Airport - the Stratoliner, Dash 80 and Concorde. Each represents a significant advancement in the technology of flight.

The three airliners, and scores of other historically significant artifacts, are headed for permanent display at the Smithsonian's National Air and Space Museum's new Steven F. Udvar-Hazy Center near Dulles.

The luxuriously appointed Boeing 307 Stratoliner, designed in the late 1930s, was the world's first passenger airplane to be pressurized, allowing it to avoid rough weather by flying at unprecedented altitudes (20,000 feet) for transports of the era. It flew at 220 mph.

The swept-winged Boeing 367-80, which first flew in 1954, was the prototype for the Boeing 707. It was America's first commercially successful jet airliner and revolutionized commercial air transportation. The Dash 80 flew at 550 mph.

The sleek, delta-winged Concorde, debuting in commercial service in 1976, is the first supersonic jet and cruises at an altitude of up to 60,000 feet. A trip on the Concorde is about twice as fast as on conventional aircraft - more than twice the speed of sound at around 1,350 mph.

The airplanes are being temporarily stored at a holding area of the airport, and will be moved into the new facility within the next few weeks. They cannot presently be viewed by the public, but will be displayed in the same section of the new museum annex when it opens Dec. 15.