MOSCOW - The Moscow International Air Show ended Sunday with a spectacular air display, and hope among Russian officials that new contacts would lead to a boost in aviation sales next year.

Nikolai Moiseyev, deputy head of the space agency Rosaviakosmos, which participated for the first year in the show, said discussions were held with representatives from 30 countries, the ITAR-Tass news agency reported.

He also said numerous countries signed preliminary agreements to buy Russian equipment or to receive upgrades of Soviet-era purchases. He didn't provide any exact details, but said that if all the contracts are realized, the deals will exceed US$5 billion.

Russia's ailing aviation industry is in significant need of foreign investment after state subsidies all but disappeared with the collapse of the Soviet Union. Military sales to foreign armed forces have outpaced civilian deals, with even Russian airlines preferring to buy Western Airbus or Boeing jets.

However, Nikolai Nikitin, director general of the manufacturer MiG, announced a deal to sell 25 Tu-334 passenger jets to the St. Petersburg-based Pulkovo Airlines, ITAR-Tass said. Details were still be worked out, said Nikitin, whose company assembles the new Tupolev jets. Tupolev had a successful show, earlier announcing a deal to sell 10 Tu-204 passenger jets to Russia's Transaero airline.

The air show, held every two summers at a former top secret Soviet air base outside of Moscow, has been an opportunity for Russia to showcase its aviation prowess and promote its products. This year, more than 500 firms participated, including companies from countries such as the United States, France, Britain, China and Chile.

For the first time ever, the U.S. Air Force brought some of its military planes to the show, exhibiting the Cold War workhouse B-52 bomber and flying an F-15 fighter jet in daily displays.

French and Italian fighter jets also participated in the acrobatic displays over the expansive Zhukovsky airfield.

Russia's NTV television estimated that some 700,000 people attended the six-day festival, which was held amid the tightest security. Lines of police roamed the grounds, and bomb-sniffing dogs inspected all entering vehicles.