Gemini IX (space mission in
Project Gemini)
June 3-6, 1966
Thomas P. Stafford,
Eugene A. Cernan
3 days, 21 hours
Rescheduled from May to rendezvous and dock with augmented target docking adapter (ATDA) after original Agena target vehicle failed to orbit. The ATDA shroud did not completely separate, making docking impossible. Three different types of rendezvous, two hours of EVA, and 44 orbits were completed.
Source: NASA