Expedition 11 was a long-duration International Space Station increment flown by Sergei Krikalev and John Phillips. The crew launched on Soyuz TMA-6 with ESA astronaut Roberto Vittori on April 15, 2005, docked with the station on April 17, and formally took over after the Expedition 10 crew undocked on April 24. NASA describes the increment as a caretaker crew period that supported station maintenance, science, Earth observation, and preparations for the Shuttle return-to-flight era. Krikalev commanded the expedition while Phillips served as NASA ISS science officer and flight engineer.