The Soviets, generally unsuccessful in selling their large planes outside the Soviet bloc, may soon be trying with a small one.

The candidate would be the AN28, a small commuter airplane on display in the West for the first time at the Paris Air Show - a plane that can be converted in minutes from a 17-seat passenger plane to an all-cargo plane by folding up the seats into the sides.

In an unusually detailed and friendly interview aboard the plane here. Oleg Konaninovich Antonov, the designer of the AN28, said an initial order for the plane from Aeroflot will be produced in Poland at a factory in Pezetel, which also has been given a license to produce the plane for sale to others.

"I tell all my commercial people they have given away the golden calf to the Poles," Antonov said.

The interview, granted two Western journalists, was conducted with the aid of an American who speaks fluent Russian.

Antonov, now a young-looking 73, was the designer of what is considered the most successful Russian designed plane, the AN2 (for Antonov), a biplane first flown in commercial service in 1947 and still being produced today. There are more than 10,000 of the 10-seater planes in operation today, Antonov said. It is considered a standard workhorse, much as the DC3 was.

"We expect this new aircraft will be even more successful," be added.

The AN28 was designed specifically to replace the AN2, Antonov said, ad is tailored to serve unpaved runways in the "boondocks" of the vast Soviet territory. "Our nation is in the same stage of development as the United States 100 years ago," he said. "There is a huge territory just opened that is rich in many minerals and natural resources - oil, natural gas, rare and precious metals," he said. "And the geologists are most talented in finding promising deposits the furthest away from airports and roads," he said with a laugh.

As a result, he needed to design an airplane specifically to operate without an airport, a plane that could land on unpaved surfaces with possibility of rocks and other debris and very little runway space.

The plane created has maximum visibility from the cockpit to allow the pilot to "buzz by and eyeball" the possible landing site at a minimal approach speed before turning around and landing in any weather, Antonov said. The engine turboprop is said to have extremely short takeoff and landing capabilities. "Our goal was frankly to develop the safest, most foolproof plane in the world," Antonov said.

It will take the Polish factory 1 1/2 to two years to come up to full production. The asking prce for the plane will be in the 80,000 range, he estimated.