Number in parentheses indicates number of spaceflights by each individual prior to and including this mission.
Atlantis carried the SPACEHAB double module providing additional middeck locker space for secondary experiments. During the five days of docked operations with Mir, the crews transferred water and supplies from one spacecraft to the other. A spacewalk by Linenger and one of his Russian cosmonaut crewmates will be after Atlantis departs.
The STS-81 mission included several experiments in the fields of advanced technology, Earth sciences, fundamental biology, human life sciences, microgravity, and space sciences. It was hoped that data would supply insight for the planning and development of the International Space Station, Earth-based sciences of human and biological processes, and the advancement of commercial technology.
STS-81 will involve the transfer of 5,975 pounds (2,710 kg) of logistics to and from the Mir, the largest transfer of items to date. During the docked phase, 1,400 pounds (635 kg) of water, 1,137.7 pounds (516.1 kg) of U.S. science equipment, 2,206.1 pounds (1,000.7 kg) of Russian logistics along with 268.2 pounds (121.7 kg) of miscellaneous material will be transferred to Mir. Returning to Earth aboard Atlantis will be 1,256.6 pounds (570.0 kg) of U.S. science material, 891.8 pounds (404.5 kg) of Russian logistics and 214.6 pounds (97.3 kg) of miscellaneous material.
First Shuttle flight of 1997 highlighted by return of U.S. astronaut John Blaha to Earth after 118-day stay aboard Russian Space Station Mir and the largest transfer to date of logistics between the two spacecraft. Atlantis also returned carrying the first plants to complete a life cycle in space — a crop of wheat grown from seed to seed. This fifth of nine planned dockings continued Phase 1B of the NASA/Russian Space Agency cooperative effort, with Linenger becoming the third U.S. astronaut in succession to live on Mir. Same payload configuration flown on previous docking flight — featuring SPACEHAB Double module — flown again.
Blaha joined Mir 22 crew of Commander Valeri Korzun and Flight Engineer Alexandr Kaleri on September 19, 1996, when he arrived there with the crew of STS-79. Linenger was to work with the Mir 22 crew until the arrival in February of the Mir 23 crew of Commander Vasili Tsibliev, Flight Engineer Aleksandr Lazutkin and German researcher Reinhold Ewald. Ewald was to return to Earth with the Mir 22 cosmonauts after a brief stay on the station. Astronaut Michael Foale replaced Linenger on Mir when the STS-84 mission arrived in May 1997.
Docking occurred at 22:55 EST, January 14, followed by hatch opening at 00:57 January 15. Linenger officially traded places at 04:45 with Blaha who spent 118 days on the station and 128 days total on-orbit. During five days of mated operations, crews transferred nearly 6,000 pounds (2,722 kilograms) of logistics to Mir, including around 1,600 pounds (725 kg) of water; around 1,138 pounds (516 kg) of U.S. science equipment; and 2,206 pounds (1001 kg) of Russian logistical equipment. About 2,400 pounds (1,100 kg) of materials returned with Atlantis from Mir.
Crew also tested on Shuttle the Treadmill Vibration Isolation and Stabilization System (TVIS), designed for use in the Russian Service Module of the International Space Station. Another activity related to International Space Station involved firing the orbiter's small vernier jet thrusters during mated operations to gather engineering data.
Undocking occurred at 09:15 EST, January 19, followed by flyaround of Mir.
No significant in-flight anomalies experienced with orbiter.