An Antonov An-140, Azerbaijan Airlines Flight 217 from Baku, Azerbaijan, to Aktau, Kazakhstan, heading across the Caspian Sea, crashes, killing 23 people.

The Antonov An-140 is a turboprop regional airliner, designed by the Ukrainian Antonov ASTC bureau as a successor to the Antonov An-24, with extended cargo capacity and the ability to use unprepared airstrips.

Azerbaijan Airlines Flight 217 was a scheduled passenger flight between Baku and Aktau, Kazakhstan that crashed into the Caspian Sea at ca. 22:40 on 23 December 2005. The flight was operated by an Antonov An-140.

Baku is the capital and largest city of Azerbaijan, as well as the largest city on the Caspian Sea and in the Caucasus region. Baku is 28 metres (92 ft) below sea level, which makes it the lowest lying national capital in the world and also the largest city in the world below sea level. Baku lies on the southern shore of the Absheron Peninsula, on the Bay of Baku. Baku's urban population was estimated at two million people as of 2009. Baku is the primate city of Azerbaijan—it is the sole metropolis in the country, and about 25% of all inhabitants of the country live in Baku's metropolitan area.

Azerbaijan, officially the Republic of Azerbaijan, is a transcontinental and landlocked country at the boundary of West Asia and Eastern Europe. It is a part of the South Caucasus region and is bounded by the Caspian Sea to the east, Russia's republic of Dagestan to the north, Georgia to the northwest, Armenia and Turkey to the west, and Iran to the south. Baku is the capital and largest city.

Aktau is a city in south-west Kazakhstan, on the eastern shore of the Caspian Sea. Aktau is on the Mangyshlak Peninsula in the Mangystau Region.