West German, 19, Interrogated : Moscow Puzzle: How Did Flier Penetrate Defenses?

The young West German pilot who put his light plane down Thursday night in Red Square, apparently as a lark, was being interrogated Friday by concerned Soviet authorities.

Officials said that although the pilot, 19-year-old Mathias Rust of Hamburg, may look on the flight as a stunt, it is no laughing matter to the Soviet government and may have serious military and political ramifications.

Soviet authorities were described as anxious to learn how Rust managed to penetrate Soviet airspace and proceed, in broad daylight, for 560 miles or so from Helsinki, the capital of Finland, to Moscow through what is reputed to be the world’s finest air-defense system, made up of jet fighters, missiles and anti-aircraft guns.

Further, they would like to know how Rust, flying a single-engine, four-seat Cessna, could circle the Soviet capital, over which all flights are prohibited, and put down literally next to the Kremlin, the seat of Soviet power.

“The implications for Soviet defenses, and for the whole debate on how a war could start by mistake, are astounding,” a military analyst said.

The Soviet government was thought to be highly embarrassed by the incident.

Some observers said it might be seized on by opponents of Soviet leader Mikhail S. Gorbachev, who returned Friday from a Warsaw Pact meeting in East Berlin, to criticize his controversial policy of glasnost , or openness.

And there was speculation that heads will roll among officials responsible for air defenses in the areas involved.

Adding to the embarrassment, the flight took place on a day set aside for honoring the Border Guard, 500,000 men of the KGB, the agency responsible for security and espionage.

Military analysts pointed out that even sophisticated air-defense systems are not necessarily geared to detect and bring down low-flying light planes, which are not expected to be used in any serious attack.

Soviet Boast

Yet two years ago, Pravda, the Communist Party daily, said the defense network was capable of striking targets high or low, at any speed and in any conditions of visibility.

Tass, the official news agency, said Friday, “The flight of the plane above Soviet territory was not cut short, and it landed in Moscow.”

Its three-paragraph dispatch said “competent bodies” are investigating, but it did not say if Rust was arrested or would face criminal charges.

The news agency said Rust came in from the Baltic Sea near the Estonian coastal city of Kokhtla-Jarve, on the Gulf of Finland about 90 miles southeast of Helsinki. Kokhtla-Jarve is on the Gulf of Finland almost directly between Helsinki and Moscow, indicating that the young pilot made a beeline for the Soviet capital.

No Embassy Contact

The West German Embassy reported late Friday that it had had no contact with Rust, who under Soviet rules can be held for three days without official notification to his country’s ambassador.

Rust was quickly taken away not long after he landed about 6 p.m. in Red Square, which covers about 85,000 square yards between the red-brick wall of the Kremlin and the onion-shaped domes of St. Basil’s Cathedral.

Witnesses said that at first they thought the landing was an official operation or perhaps connected with the shooting of a film.

The pilot swooped in from the south past the Moscow River, they said, and then low over the big GUM department store, on the northeast side of the square, before landing on the cobblestones.

Signed Autographs

The young man waved to the startled onlookers, climbed out and signed a few autographs with the words “Hamburg-Moscow.” His plane was said to bear the markings of a Hamburg flying club.

Policemen on duty at the square reportedly behaved casually at first, and some time elapsed before a large number of security officers arrived and sealed off the area.

Juliet Butler, a British woman who works in Moscow as a governess, said: “When I went to take a picture of (the police),” they just giggled. They clearly had no instructions from high up at first. It took them some time to realize it was not officially organized, but then guards from the Kremlin escorted (Rust) in through the Spassky Gate. He seemed quite happy as he was taken away.

“Then some higher officers came in big cars and seemed to get things more organized. About six army trucks drew up, and Red Square was sealed off. Metal railings were put around the plane, and about seven policemen stood around to guard it.”

One report suggested that a young woman was in the plane with Rust, but this could not be confirmed, and later versions cast doubt on the report.

Computer Operator

According to Finnish and West German authorities, Rust is a computer operator and lives in Hamburg. He started flying lessons two years ago at the age of 17, intending to be a professional pilot, and joined the Hamburg Air Club.

He was described by his mother, Monika, as “a quiet young man of wonderful character with a passion for flying.”

“We still can’t believe it,” she told reporters in Hamburg. “I am unhappy because I don’t know the reason for his flight.”

Helmut Gass, president of the flying club, said Rust rented a four-place Cessna 172B and installed extra gas tanks in the passenger seats. This is said to have given the plane a range of about 1,000 miles.

Rust took off from Hamburg on May 13 for the German resort island of Sylt in the North Sea, then flew on to the Shetland Islands north of Britain. From there he crossed the North Atlantic to Iceland, then to Bergen, on the Norwegian coast, and to Helsinki.

Stockholm Flight Plan

According to Finnish authorities, he arrived in Helsinki on May 25 and filed a flight plan for Stockholm, the Swedish capital.

Reuters, the British news agency, quoted Rust’s mother as saying that “he called the last time from Helsinki, on Tuesday; he was going to fly home via Stockholm.” She said he would have had no political motive for flying into the Soviet Union.

Rust took off Thursday from Malmi, a military airport outside Helsinki that is also used by private planes, and gave his destination as Bromma Airport at Stockholm.

Finnish authorities said he headed west toward Stockholm and flew in that direction for several minutes, but then headed toward the Soviet Union. Officials in Helsinki, thinking Rust had lost his way, started a search late Thursday, then called it off Friday after getting word that he had put down in Moscow.

May Have Been Lost

Aviation officials speculated that Rust may indeed have lost his way. But others pointed out that visibility in the area was good, that the flight path over the Baltic Sea to Sweden hardly resembles the Russian landscape and that Rust seemed to know where he was when he landed.

“Despite his age,” said Werner Schultz, a flight instructor at the Hamburg club, “Rust is an experienced pilot. His solo flight, especially the stretch from the Shetlands to Iceland, deserves recognition. He is a good pilot, with no tendency toward daredevil flying.”

He took an enormous risk, specialists here say. In 1983, a Soviet fighter shot down a Korean airliner in Soviet airspace in the Far East. All 269 people on board were killed.

Penetrating Soviet airspace without permission is strictly prohibited. Foreign commercial traffic is closely monitored, and even Soviet military aircraft are banned from operating over central Moscow.