For the space-age commuter, L.A. to Washington in 33 minutes

Ladies and gentlemen, please fasten your seatbelts for takeoff. Once airborne, we will come through the cabin with complimentary drinks, but there will be no meal served since our flight time from Washington to Los Angeles is 33 minutes. Thirty-three minutes?

Sometime in the 21st century such gazelle-quick flights may become possible, if work now gearing up on a new generation of aircraft bears fruit.

The focus of the research is on ``hypersonic'' aircraft, planes that might travel at five times the speed of sound. By contrast, the supersonic Concorde cruises at speeds near Mach 2 (1,350 m.p.h). Eventually, Mach 25 aircraft are envisioned -- ones quick enough to spirit passengers from New York to Tokyo in two hours.

Formidable technical hurdles to developing a hypersonic plane remain, however, and many skeptics remember the problems the US had with its supersonic transport program, which Congress killed in 1971. Still, an accelerated research program is under way to develop the technology for an ``aerospace'' plane that would be able to take off from conventional runways and enter low-Earth orbit in flight.

Interest in the superplane is being driven by advances in technology and the belief that faster, more flexible aircraft will soon be needed for many civilian and military purposes. Some aerospace planners, for instance, have long been captivated by the notion of using hypersonic aircraft to link the United States with far-flung trading partners, particularly in Asia. Hence, the name often given the plane: the ``Orient Express.''

Given advances in technology and the growing economic power of Pacific Rim nations, ``the time has come when we can no longer be in this static condition of flying airplanes that were invented in the 1950s,'' says Scott Crossfield, a congressional consultant and hypersonic enthusiast, as well as a former X-15 pilot.

The idea of an aerospace plane got a boost recently when President Reagan singled it out in his State of the Union address. Support for the radical aircraft, however, had been building before that among some aerospace lobbyists and Pentagon officials. Last spring, a blue-ribbon presidential advisory panel recommended that research on a hypersonic airliner be made a top US priority.

``We are at the point where we are convinced it is technologically feasible,'' says Lana Couch, an aerospace plane program manager with the National Aeronautics and Space Administration (NASA).

The Reagan administration is seeking $600 million over the next three years to research the technology for hypersonic aircraft. It projects that $3 billion might be needed between now and the mid-1990s to develop an experimental plane. A commercial version probably wouldn't be ready until after the year 2000.

Initial funding would be divided between NASA and four Pentagon agencies. This reflects the diversity of interest in the aircraft, as well as conflicting views about its uses. The Air Force says aerospace planes might be useful for photo reconnaissance or even bombing missions.

Strategic Defense Initiative officials are interested in an inexpensive cargo carrier for servicing a space-based missile defense system. Others would like to see a 300- to 500-passenger civilian transport.

Building an aerospace plane will take plenty of technological talent. A chief hurdle will be the engines. One idea being looked at is the ``air turboramjet,'' which combines traditional turbine and rocket technology to achieve efficient operation at all speeds. Variations of the ramjet may be able to propel a plane to Mach 25 (more than 17,000 m.p.h.), the velocity needed for orbit. A hypersonic passenger plane would probably cruise at Mach 5. More work is also needed on lightweight, heat-resistant materials for such an aircraft, as well as on its aerodynamics.

All this will cost money, and Congress is likely to look hard at any spending increases in these deficit-ridden times.

Following the explosion that destroyed the space shuttle Challenger, some aerospace specialists have argued that NASA should develop a hypersonic aircraft rather than press for a new orbiter.

Moreover, questions are bound to surface over whether there is a commercial market for hypersonic passenger planes.

Advocates argue such aircraft hold some advantages over supersonic planes. They fly high enough to reduce problems with sonic booms, and because several round trips a day could be made to even the most distant cities, more productive use could be made of each plane.

Yet too much speed also has drawbacks: More daily flights per plane will mean fewer planes are needed. Nor will there likely be bargain-basement fares. ``It is far from clear anybody is going to be able to afford the tickets,'' says John Pike, a space specialist with the American Federation of Scientists.