U.S., Soviet Union Near Accord on Air Service : Transportation: More flights to more cities are expected as relations between the superpowers continue to thaw.

The United States and the Soviet Union are moving toward a major increase in scheduled and charter air service, opening for the first time a wide array of destinations in each nation.

The development represents one more signal of closer relations between the superpowers and opens a potential opportunity for U.S. commercial air carriers.

“Clearly, it would appear that the market is going to increase more rapidly in the future,” said Pamela Hanlon, a spokeswoman for Pan American World Airways, now the only U.S. carrier that flies into the Soviet Union.

“Potentially it’s an excellent market,” she said.

If the tentative agreement reached in London last week bears fruit, it would normalize and greatly expand air service disrupted a decade ago as the United States imposed sanctions to retaliate against the 1979 Soviet invasion of Afghanistan and the 1981 Soviet-encouraged crackdown against dissidents in Poland.

Under the preliminary agreement, U.S. airlines would increase scheduled service to Moscow and Leningrad and gain new rights to serve six additional Soviet cities, including two in the Soviet Far East, according to the State Department.

A department official said Wednesday that these cities include Kiev, the capital of the Ukraine; Riga, the capital of Latvia; Minsk, the capital of Byelorussia; Tbilsi, the capital of Soviet Georgia, and Khabarovsk and Magadan in the Soviet Far East. Khabarovsk is a station on the Trans Siberian Railroad north of Vladivostok. Magadan is a port on the Sea of Okhotsk, which opens to the Pacific.

In return, the Soviet airline Aeroflot would be permitted to increase its trans-Atlantic service to New York and Washington and would gain new rights to serve Chicago and Miami with onward service to two undisclosed points in South America.

Aeroflot service over the Pacific also could begin to Anchorage, and to San Francisco with a stop in Anchorage, the State Department said.

Airlines of both nations also could increase the number of weekly flights and increase the number of airlines designated to serve the expanded routes, the department said.

Hanlon said Pan Am sees the new development as an opportunity to expand more rapidly in a modest but steadily increasing market.

Pan Am, which began non-stop service to Moscow two years ago with three flights a week, added a flight last year and will operate five flights a week this summer, Hanlon said.

“We are currently looking to increase that to seven non-stops next year,” she said.

The spokeswoman said Pan Am and other U.S. carriers would not necessarily open air service to each of the new possible destinations inside the Soviet Union but would look at each city “to see if the market is there.”

The tentative agreement also would allow the United States and the Soviet Union up to 100 charter flights a year over the Atlantic.

The State Department said “positive consideration” also would be given to trans-Pacific charter flights between the two countries.

The preliminary agreement was reached by U.S. and Soviet negotiators at a second round of the London talks. A third round will be convened in London in late April to discuss financial provisions and other outstanding issues.

Then-President Jimmy Carter ordered Aeroflot to stop its service to New York after the Soviet invasion of Afghanistan.

In 1981, then-President Ronald Reagan cited Soviet-inspired repression in Poland in ordering Aeroflot to terminate its service to Washington.

The latter action halted all Soviet air service to the United States with the exception of Aeroflot flights carrying diplomatic personnel and supplies intended for Soviet embassies and consulates.

In 1983, Reagan ordered Aeroflot’s offices in New York and Washington closed in protest over the shooting down of a South Korean jetliner by Soviet warplanes.

Commercial flights between the two nations were resumed in April, 1986, with regularly scheduled Aeroflot service to Washington and Pan Am flights to Moscow.

The next year the two nations signed an agreement permitting an expansion of air service beginning in May, 1988.