WANT TO SEE the plane that dropped the bomb on Hiroshima? Satisfy your latent Trekkie longings by checking out the Enterprise? Find the place where airmail began? Or reflect on captured aircraft -- some with bullet holes -- from World Wars I and II, and Korea?

You've come to the right place. Not only does Washington have the Air & Space Museum -- at more than 10 million visitors annually, the most popular museum in the world, they say -- but the town's outskirts are also studded with mini-monuments to air and space. The NASA center in Greenbelt creates, tests and tracks satellites; the Smithsonian's Paul Garber Facility in Silver Hill is busily restoring aircraft like the Enola Gay, the B29 of the Hiroshima mission; the Marine Air and Ground Museum at Quantico can give you a condensed version of flight in its corner of the military; and the Academy of Model Airplanes in Reston has a museum of miniatures of everything from early biplanes to the space shuttle.

Here's how to tour them and more. They're all free.

ACADEMY OF MODEL AIRPLANES -- Reston, 435-0750. The academy's first floor is given over to models -- of engines, radios, airplanes. Many are scale models -- painstaking miniatures that take dozens, sometimes hundreds of hours to make.

On the ceiling, mobiles full of models turn; rubber-band-powered, gliders, pre-WWII planes, radio-controlled and control-line craft. The Academy also demonstrates how modeling helps aeronautical engineers experiment and develop ideas -- such as the space shuttle.

Open Monday through Friday, 8:30 to 5, Saturday by appointment only. To get there, from the Beltway take I-66 west to Route 7 Tysons Corner exit to left on Route 606 at Reston sign. Go to Reston Avenue (Bradlee's on your right) and make another left. Make a left at first light, Sunset Hills Drive, and go past he light for another half-mile to Samuel Morris Drive, and make a right. Academy is on your right.

AIR AND SPACE MUSEUM -- on Independence Avenue between Fourth & Seventh streets, 357-1400. It has something for everybody -- from a model of Star Trek's Enterprise (in the Flight Testing Gallery on the 2nd floor) to a film of Sid Caesar "breaking" the sound barrier (in Jet Aviation on the first floor); from a hangar deck where planes seem to land and take off (Sea-Air Operations, second floor) to a puppet show in the Balloon & Airships Gallery (second floor). The most popular area is probably Space Hall, with its tall rockets and tour of Skylab.

The museum also shows some magnificent giant-screen films at its Samuel P. Langley Theater -- "The Dream Is Alive," "To Fly!", "Living Planet" and "Flyers," from 10:10 to 5 p.m. daily. The Albert Einstein Planetarium shows "Comet Quest" from 10:50 to 4:50 daily. Admission to all shows is $1.50 for adults, 75 cents for children, students and senior citizens.

Open seven days a week, 10 to 5:30.

ANDREWS AIR FORCE BASE -- Suitland, 981-4511. Tours by appointment only, during the week from 10 to 3. Depending on the group, a tour may include a drive around the base and down the flight-line to see transport, passenger and executive jets, helicopters and fighter aircraft. The president's plane, Air Force 1, is not on display. Groups of 10 or more should call or write four weeks ahead to: 1776 Air Base Wing/PAC, Andrews Air Force Base, Maryland 20331-5000.

COLLEGE PARK AIRPORT MUSEUM -- College Park, 864-1530. The exhibit, in a two-room trailer, traces the history of this, the nation's oldest airport in continuous use. The airport opened in 1907. Among other things it served as an Army aviation school and was the site of the start of regular airmail. Uniforms, scale models of planes and sites and other paraphernalia are on display. Outside the museum are modern Cessnas and Pipers; on a good day, you can watch a few take off or land.

The museum is open Friday, Saturday and Sunday from 10 to 4. To get there from the Beltway, take U.S. 1 south; go about four miles past the University of Maryland to the Quality Inn; make a left on Calvert Road. Go another half-mile, make a left on Corporal Frank Scott Drive. The airport is at the end of the road.

GODDARD (NASA) SPACE CENTER -- Greenbelt, Md., 344-8981. Guided tours of communications and satellite tracking facilities every Thursday at 2, or by prior arrangement. Visitors center open Wednesday through Sunday from 10 to 4. More than 70 percent of NASA's orbiting materials were developed and checked at Goddard. The visitors center displays satellite test models and a 100-foot Delta launch vehicle. You can pretend you're an astronaut and have your picture taken behind a photo cutout. There are information booths with sound and light shows on space matters, and one of the area's cheekiest computers to answer your questions ("Thank you very much, I found your questions trivial."). There's also a lab where, by appointment, teachers can research and duplicate curriculae, slides, photos, filmstrips and audio cassettes. From the Beltway, take the Baltimore Washington Parkway toward Baltimore. Stay in the right lane, go under the Greenbelt Road overpass, and take the ramp off to your right. Go to light, and turn left onto Greenbelt Road about two miles past the main gate, turn left onto Soil Conservation Road. Take your next left into the gate, and go to the Visitor's Center.

MARINE AIR & GROUND MUSEUM -- Quantico, Va. 703/640-2606. Two buildings and an outdoor section display Marine Corps and enemy aircraft, uniforms, vehicles, balloon carriages, helicopters, amphibious vehicles and artillery. Closed at present because of to lack of heat; museum will reopen April 1. Open Thursday through Sunday from 10 to 5; tours available with 48-hour warning. From I-95, go to either the North or South Gate of the Quantico Marine Base, and follow signs to museum.

NASA/WALLOPS FACILITY -- Wallops, Island, Va. 804/824-3411, Ext. 584 or 298. For those on their way to Chincoteague, this makes a nice stop -- or return visit. The collection highlights the growth of rocketry, and displays the history of the space program. On Route 175 about 6 miles from Route 13, and 6 miles from Chincoteague.

PAUL GARBER FACILITY -- Silver Hill, Md. 357-1400. Four "no frills" buildings crammed with planes from the early days of flight to the jet age, plus a restoration building where they're working on the Enola Gay, a SPAD XIII (WWI biplane, with fabric-covered wings shot through with bullet holes), an Arado (WWII German aircraft) and a Kingfisher (large amphibious aircraft). It can be toured only by appointment. Tours are given at 10 Monday through Friday and on Saturday, Sundays and holidays at 10 and 1. Call to be fitted in to a tour. Facility will hold an open house April 26 and 27. To get there, from the Beltway take the Branch Avenue, Silver Hill Exit (Rte. 5 North); make a left, go one block to traffic light, go right on Rte. 5 and follow for 1 mile to St. Barnabas Road. (Rte. 414); continue on St. Barnabas half a mile to Facility, directly across Silver Hill Road intersection.

SPACE SHUTTLE -- Nothing official, mind you, but we happen to know the retired space shuttle "Enterprise" is resting at Dulles airport, about a mile from the observation tower. On a clear day, you can get a good glimpse of it; the area is not open to the public. The Smithsonian hopes to build an annex to house the "Enterprise," possibly near the airport, if Congress agrees.