Orbiter OV-104
See also Space Transportation System and space shuttle
This orbiter is currently active.

Entered service October 3, 1985.

    STS-51J    10/03/85
    STS-61B    11/26/85
    STS-27    12/02/88
    STS-30    05/04/89
    STS-34    10/18/89
    STS-36    02/28/90
    STS-38    11/15/90
    STS-37    04/05/91
    STS-43    08/02/91
    STS-44    11/24/91
    STS-45    03/24/92
    STS-46    07/31/92
    STS-66    11/03/94
    STS-71    06/27/95
    STS-74    11/12/95
    STS-76    03/22/96
    STS-79    09/16/96
    STS-81    01/12/97
    STS-84    05/15/97
    STS-86    09/25/97
    STS-101    05/19/00
    STS-106    09/08/00
    STS-98    02/07/01
    STS-104    07/12/01

Atlantis was the fourth active orbiter in the fleet, and was intended to be the last of the line. This was changed when Challenger was destroyed, and Endeavour was built to replace it.

Atlantis was able to make use of many of the same design improvements that aided Discovery, including a reduction in weight of some 6,974 pounds, and nearly half the construction time of the original orbiters.

During the construction of Atlantis and Discovery, spare replacement parts were commissioned, amounting to an estimated $389 million. These included a spare aft-fuselage, mid-fuselage, forward fuselage halves, vertical tail and rudder, wings, elevons and body flap. These spare parts were later used to build Endeavour.

The rest of the orbiter fleet:
Enterprise * Columbia * Challenger * Discovery * Endeavour

ed note: In 2006, NASA anounced plans to retire Atlantis and use her for spare parts for Discovery and Endeavour.