By July 2014, the launch was scheduled by NASA for "no earlier than" December 2014, with docking to the station projected to occur two days after launch. Originally scheduled for a 16 December 2014, launch, the mission was changed to 19 December 2014, in order to give SpaceX more preparation time for a successful launch. The launch was postponed again to NET 6 January 2015, in order to allow more tests before committing to a firm launch date. On 6 January 2015, the launch attempt was placed on hold at 1 minute 21 seconds prior to scheduled lift-off after a member of the launch team noticed actuator drift on one of two thrust vector control systems of the Falcon 9second stage engine. As this launch had an instantaneous launch window, meaning no delays are possible in the launch sequence, the flight was postponed to 9 January 2015. On 7 January, the flight was rescheduled for 10 January 2015. The Falcon 9 rocket carrying the CRS-5 Dragon spacecraft successfully launched on 10 January 2015 at 9:47 UTC. Dragon reached the station on 12 January. It was grappled by the Space Station Remote Manipulator System at 10:54 UTC and berthed to the Harmony module at 13:56 UTC.
Primary payload
The Dragon spacecraft for CRS-5 carried of cargo to the ISS. Included in this was of provisions and equipment for the crew, of station hardware, of science equipment and experiments, and the Cloud Aerosol Transport System. CATS is a LIDAR remote sensing instrument designed to measure the location, composition and distribution of pollution, dust, smoke, aerosols and other particulates in the atmosphere. CATS is to be installed on the Kibo external facility and is expected to run for at least six months, and up to three years. Upon completion of its stay, Dragon was loaded with of outgoing cargo, returning it back to Earth.
SpaceX attempted a landing on the drone ship on 10 January. Many of the test objectives were achieved, including precision control of the rocket's descent to land on the platform at a specific point in the south Atlantic Ocean and a large amount of test data was obtained from the first use of grid fin control surfaces used for more precise reentry positioning. However, the rocket was destroyed due to a hard landing. Musk said that one of the possible problems was the grid fins running out of hydraulic fluid. The SpaceX webcast indicated that the boostback burn and re-entry burns for the descending first stage occurred, and that the descending rocket then went "below the horizon," as expected, which eliminated the live telemetry signal. Shortly thereafter, SpaceX released information that the rocket did get to the drone spaceport ship as planned, but "landed hard... Ship itself is fine. Some of the support equipment on the deck will need to be replaced." SpaceX made a video of the landing attempt available on Vine.