After a day and night of rain, smoke still curled yesterday from the debris of the Reston town house where Susan and Harry Ottinger died in Tuesday's crash of a light plane in Reston.

The explosion touched off when the plane struck the Ottinger town house, killing the pilot as well as the young couple [WORD ILLEGIBLE], was so powerful, the fire so intense, that the house and its contents were incinerated.

Only a few scraps of memorabilia were recovered from the debris yesterday by fire fighters and federal aviation safety investigators: the beaded necklace that the Ottinger's 7-year-old daughter, Jenny, had made from a leather thong and a color snap-shot of Jenny and her father at the Bicentennial parade in Washington on July 4, 1976.

he holocaust in the Hunters Green cluster of town houses wiped out almost all physical evidence of the family history. The home was so thoroughly destroyed that positive identification of the bodies found inside still has not been made but no one believes they are other than Jenny's parents.

This is because from his 15th floor office in Reston's International Center, Harry Ottinger could see when Susan returned home from her job at the Montessori Country School in Herndon and he would walk across the 17th fairway of the Reston South golf course and join her for lunch.

The couple had moved to the Hunters Green cluster of Reston town houses last spring so they could have lunch together, as well as get by with one car, friends recalled.

Tuesday, by all accounts, they were having lunch when a twin-engine Piper Aztec plunged out of the thick fog hovering over the area at 2:12 p.m. With its wings at a steep - a witness called it desperate - angle, the plane struck the house.

The Ottingers apparenty died instantly. JOe L. Reid, the pilot, died strapped in his blue seat.

Reid, 41, had delayed his departure from Ohio State Univesity Airport in Columbus several times during the morning Wednesday in hopes the weather would improve.

Finally, however, he took off, but listed Columbus as his alternate destination - an unusual procedure - and carried enough fuel for a round-trip to Washington. Normally an alternate destination would be closer to the original destination.

Jack Eggspueller, chairman of the department of aviation at Ohio State and Reid's boss, had himself started out for Washington in the same plane on Thanksgiving Day, but abandoned the trip before takeoff when the plane began spewing black smoke.

Eggspuehler said in a telephonee interview that a problem with the fuel mixture was corrected by mechanics before Reid took off Wednesday.

"Our mechanics really went over that plane well." Eggspuehler said. "because we knew it was leaving the area and going to a new owner." A number of small things had been repaired on the plane within recent weeks, Eggspuehler said.

The new owner was to be Louis Boursa, who runs the parking concession at Washington National Airport under contract to the Federal Aviation Administration, which owns the airport.

Boursa said yesterday that the plane was being brought to Washington for his approval and was to be checked out by mechanics at the Woodbridge airport.

Eggspuehler said that he had introduced Boursa to the plane's owner, Harrry Riggs, a Kentucky man. Eggspuehler and Riggs are part owners of a "company that teaches an aviation course around the country." Eggspuehler said. The plane, a two-engine, six-seated Piper Aztec, had been kept at the Ohio State University Airpot.

A member of the National Transportation Safety Board's crash investigation team was visting Ohio State University airport yesterday afternon to check the maintenance logs, pilot records and other information there.

Gerald T. McCarthy, who was heading the safety board investigation at the crash site, said yesterday that almost all of the aircraft had been recovered. "It's tough," he said, "because the house and the plane were so mixed together."

It is much too early to tell the cause of the accident and board investigators always are extremely careful not to jump to one conclusion and then discover days later that the pilot had a heart attack, for example.

Both engines of the plane were extracted from the wall of the home of Paul Luke near the Ottinger house and were taken to Dulles Airport yesterday for examination.

"We're very interested in the engines." McCarthy said. He said the engines were badly damaged by the impact and it was hard to tell at this stage if they had been working properly.

McCarthy said a number of witnesses had been interviewed; that there were the inevitable conflicts in the stories. However, he said, it was clear the accident was "not a classic stall and spinout."

The plane had good, straight-line velocity, either from engines or gravity, when it hit the row of townhouses, then caught fire. In a "classic stall and spinout" the plane would not have been traveling in a straight line.

An autopsy was scheduled on the pilot yesterday, but the results had not been reported to the board team.

Neighbors of the Ottingers said yesterday they believed Reid was trying to guide his plane onto the 17th fairway when it plowed through the second floor of the Ottinger house before coming to rest in an open area to the rear. Underneath the plane and near it were the contents of bureaus from the second floor bedrooms, long-playing records, and shattered pieces of furniture. Neighbor Carole Cohen, still dazed almost 24 hours after the disaster, walked back and forth in front of the rubble and remembered the Ottingers, her friends and next door neighbors.

"He used to come home and have lunch with his wife," Mrs. Cohen said. "How many husbands come home and have lunch with their wives?"

Last weekend, Mrs. Cohen hadd given Mrs. Ottinger a lamp shade that matched the new Gloria Vanderbilt wallpaper that had just been put up in Jenny's redecorated bedroom. In the front left corner - what was left of the house - the lamp shade, dented and wet but still intact, rested in the charred remains of Jenny's room.

Though the common wall separating the Ottingers' house from the Cohen house may have been structurally damaged by the crash, it served its purpose as a fire barrier. Flames from the explosion did not spread to the Cohen's roof or inside their house.

The grieving Ottinger family gathered yesterday in Bethesda at the home of Barbara Ottinger, the sister of Harry's father. Where Jenny will live has not yet been decided. "I hope we make the right decision," said Margie Anderson, Susan Ottinger's mother.

Some of the Ottinger's neighbors were upset by the continual stream of onlookers who, night and day, came to the scene, even pressing up against the white cord barrier that authorities had strung around the area.

"They're ghouls," one said. "They came up here pushing their babies in carriages and there was even someone in a wheelchair."

Fairfax County Supervisor Marthat V. Pennino (D-Centreville), whose district includes RestoN, thought differently.

"I don't think they came out to look. They cared, but they didn't know what they could do. But they had to do some thing, that's why they came."