On first sight, Russia's AN-2 planes hardly inspire confidence. They look as if they've flown straight out of the 1940s (which, in fact, is when they were first produced). As a mechanic gives the single propeller a whirl, clouds of exhaust gush out a large pipe near the front of the plane as the engine chokes and gasps its way to life.
Is this any way to travel into Russia's vast interior? Actually, it's about the only way. For almost 50 years, these small bi-planes have served as the ''workhorse'' of the Russian fleet. They can take off and land in very short distances, almost anywhere that is flat, such as a beach or open field. Called ''Aan-Dvah's'' in Russian, more than 20,000 have been manufactured over the years, making them the most common aircraft in the world.
Every year AN-2s fly to the North Pole, in a series of hops across the polar icecap. The two Russian pilots hired for this trip had been to the pole many times, reassuring passengers who did a double take upon seeing the plane.
''At first I had my doubts, but now I see these planes are wonderful: They fly so low and so slow, the views are simply fantastic,'' says London-based banker Peter de Roos, who has gone on several extended trips through the Arctic.
The only major drawbacks are limitations on space and weight. The planes can hold only about 10 passengers, plus crew. People and cargo share the same cabin.
The planes can fly about 500 km (300 miles) without refueling, depending on the load. But they lack instrument capability, so weather conditions must be good, particularly when flying over mountainous terrain.
Since most of Siberia is flat, open Arctic tundra, the AN-2 remains by far the best-suited aircraft in Russia for back-country duty.