Two Soviet TU95 "Bear" reconnaissance bombers that penetrated deep into U.S. airspace off the Virginia coast yesterday to get a look at a new U.S. aircraft carrier were detected by Airborne Warning and Control System (AWACS) planes now said to be patrolling the waters between Cuba and this country.

Although it is not uncommon for Soviet reconnaissance planes to probe around U.S. fleet maneuvers, informed sources said deployment of the Air Force's AWACS planes is a new development and is linked to growing concern about shipment of new MiG23 "Flogger" attack jets from Moscow to Havana earlier this month.

Military officials said last night that the two Soviet TU95s had taken off from their base in Cuba and were intercepted and escorted from U.S. airspace by Air Force F15 Eagle fighters and Navy F4 Phantom jets. The Soviet planes returned to Cuba.

The planes reportedly penetrated 42 miles into the U.S. air defense zone off the coast to within about one mile of the new USS Carl F. Vinson, the 93,000-ton Nimitz-class nuclear aircraft carrier. The Vinson left Newport News Sunday and is undergoing sea trials.

Pentagon officials said the TU95s were at about 1,200 feet when they came closest to the Vinson off Cape Charles, Va.

Such Soviet bombers occasionally have penetrated the U.S. air defense zone, which extends about 200 miles. U.S. jets normally intercept Soviet planes detected in the zone and escort them out.

Officials who declined to be identified told the Associated Press that yesterday's incursion was the first they could recall in which TU95s made a special round-trip from Cuba to reconnoiter U.S. naval units off the East Coast. It was not known immediately whether Soviet planes have penetrated more deeply than they did yesterday.

According to the Pentagon, an unspecified number of F15s scrambled from Langley Air Force Base, Va., and intercepted the Soviet planes about 218 miles from the Vinson.

Two F4s from Oceana Naval Air Station at Virginia Beach took over the escort about 46 miles from the Vinson, and accompanied the TU95s as they circled the carrier once before heading back toward Cuba, the Pentagon said.

The presence of about half a dozen MiG23s in packing crates at an airfield near Havana is "making a lot of people uncommonly unhappy" in Washington, one well-placed source said here yesterday.

Secretary of State Alexander M. Haig Jr. expressed concern about the MiGs yesterday during a meeting with Soviet Foreign Minister Andrei F. Gromyko in Geneva, the source said.

Although the MiGs are crated, sources here said U.S. specialists, jokingly called "crate-ologists," are sure the planes are of the modern MiG23 variety. About 30 or 40 other crates are believed to contain spare parts and other equipment.

The major unknown is whether these MiGs are primarily models used for air defense or to support ground troops or whether they are models that can carry various bombs, including nuclear weapons.

If they are the bomb-carrying variety their presence could involve a breach of understandings reached in 1962 between Washington and Moscow about keeping such weapons out of Cuba.

It is not known whether the planes are meant to stay in Cuba or are for eventual shipment to Nicaragua.