MOSCOW (AP) _ A preliminary investigation into the loss of an American commercial satellite indicated that launch operations were performed properly, a Russian military official said Saturday.

The QuickBird 1 was launched from the Plesetsk cosmodrome in northern Russia on Tuesday. It was the first of two satellites the Longmont, Colo.-based company Earth Watch planned to launch on Russian rockets.

The Russian Cosmos-3 rocket carrying the satellite ascended without trouble, but controllers lost contact with it.

A preliminary analysis showed that Plesetsk personnel involved in the launch performed properly, Col. Ilshat Baichurin, head of the Russian Strategic Missile Forces' press service, told the Interfax news agency.

Plesetsk is under the jurisdiction of the Strategic Missile Forces.

Baichurin said a commission including specialists from the Russian Aerospace Agency and the Defense Ministry would continue the investigation.

U.S. companies often use Russian space facilities to launch commercial satellites. The rockets are usually considered reliable and a good bargain compared with European and American competitors.