Anyone who's ever had a really pressing desire to look down on Washington needn't sublimate any longer: 15-minute, $49 helicopter tours of our nation's capital began operating out of National Airport this week.

Art Godjikian, who pilots a Bell Jet Ranger known to the control tower at National as November 2297 Gulf, had us hovering over the city at about 500 feet, roughly the same altitude occupied by Washington's most conspicuous whirlybird, the police department's crime copter. Godjikian, however, does not spend his evenings shining a blinding light down upon suspected felons; his major concerns seem to be smooth takeoffs and landings, and avoiding P-56, which is the prohibited airspace that extends from the White House to the Capitol.

The flights leave from a helipad near the Commuter Aviation Terminal. Nine-Seven-Gulf, which carries four passengers, lifts off with an almost imperceptible defiance of gravity and rises like a very rapidly accelerating elevator over some Crystal City apartment buildings. It proceeds past the mixing bowl of roads near the Pentagon; on to the Kennedy Center; across downtown Washington just north of the White House; past L'Enfant Plaza, where the Loew's hotel swimming pool seems as small as a hot tub; and on to Union Station, from which railroad tracks stretch out like tiny but infinite ribbons. Then it's back to National, via the Tidal Basin.

Apparently there have never been flights of this sort over Washington before. "Nobody's had the number of helicopters available to be able to dedicate some to tours," said John Neilson, the 29-year-old chief pilot of Omniflight Airways Inc., which is based at Baltimore-Washington International Airport. Omniflight has been running charter operations for 27 years, from Baltimore and three other cities. In March the company began flying out of National; for starters it will dedicate one helicopter to tours, which are available from 10 a.m. to 6 p.m. and from 7 until 9 p.m. by calling 261-1979. In addition to the 15-minute downtown tour, there is 25-minute run ($69 per person) that extends up to the Washington Cathedral, across to Catholic University and down to RFK Stadium, and a 50-minute version ($125) that ventures well out into the suburbs and includes a jaunt down the Potomac at 200 feet over the deck.

Anyone who has ever landed at National in an airplane has a pretty good idea of what Washington looks like from the air: There are a lot of buildings and monuments, and some of them are interesting. Whether one wants to extend this experience into a separate entity seems like a decidedly subjective decision and, for now, only Omniflight need speculate how popular a pastime it will become.

One consumer caveat: Helicopters are remarkably noisy, and the wise tourist will seek the left-front seat, next to the pilot, which affords a headset that replaces the rotor's roar with the chatter between aviators and air traffic controllers.