Officials say a Russian-made Sukhoi Superjet 100 with 46 people aboard has gone missing from radar screens just south of the Indonesian capital, Jakarta.
Indonesian authorities said it was unclear if the plane had crashed.
A search-and-rescue operation has been launched.
Reports say all those aboard the aircraft were guests and crew.
The aircraft, which seats up to 100 passengers, was making a demonstration flight as part of an Asian tour also scheduled to include Kazakhstan, Pakistan, Indonesia, Vietnam, Laos, and Myanmar.
The Superjet 100 made its debut in 2008.
In 2011, the first one went into service with Armenia's Armavia airlines.
A total of eight Superjet 100s are currently in service with Armavia and Russia's Aeroflot and have carried out more than 3,300 commercial flights.
Based on reporting by Interfax, ITAR-TASS, and AFP