STS-112 (ISS assembly flight 9A) was an 11-day space shuttle mission to the International Space Station (ISS) flown by Space Shuttle Atlantis was launched on 7 October 2002 at 19:45 UTC from the Kennedy Space Center's launch pad 39B to deliver the 28,000 pound Starboard 1 (S1) truss segment to the Space Station. Ending a 4.5-million-mile journey, Atlantis landed at 15:44 UTC on 18 October 2002 on runway 33 at the Kennedy Space Center's Shuttle Landing Facility.

During the launch, the ET bipod ramp shed a chunk of foam that caused a dent ~4" wide and 3" deep into the metal SRB-ET Attach Ring near the bottom of the left SRB Prior to the next mission (STS-113), an upper-level decision was made at NASA to continue with launches as scheduled. The launch subsequent to that was the ill-fated STS-107

Space shuttle Atlantis had been scheduled to visit the International Space Station (ISS) again on STS-114 mission in March 2003, however, due to the shuttle Columbia disaster all space shuttles including Atlantis were temporarily grounded. Due to rescheduling of missions Atlantis did not fly again until STS-115 on 9 September 2006.

STS-112 carried several science experiments to the space station including the Plant Generic Bioprocessing Apparatus (PGBA), Commercial Generic Bioprocessing Apparatus (CGBA), the Protein Crystal Growth Single-locker Thermal Enclosure System housing the Protein Crystallization Apparatus for Microgravity (PCG-STES-PCAM) and samples for the Zeolite Crystal Growth Furnace (ZCG) experiment.

Launch preparations for STS-112 mission were sightly delayed due to tiny cracks found within the plumbing of Atlantis' propulsion system on 17 June 2002 by an inspector. The cracks were in metal flow liners inside the main liquid hydrogen fuel lines that feed the shuttle's three main engines. Although there were no cracks in the actual fuel pipes themselves, the concern was that metal pieces from the flow liners might break off and fly into the engines. In such a worst-case scenario, the debris can potentially trigger a catastrophic engine shutdown, which in turn could lead to the loss of the crew and the shuttle.

Space Shuttle Atlantis lifted off from Launch Pad 39B of the Kennedy Space Center at 19:45:51 GMT through mostly clear blue skies. There were no problems reported during the countdown, and the ascent conformed to the standard timeline (see Space Shuttle – Mission Profile – Launch). For the first time in Space Shuttle history, a "rocketcam" video camera mounted to the upper part of Atlantis' external tank returned live video of the flight to NASA flight controllers. The video was near perfect until the two solid rocket boosters were jettisoned. At that point, the exhaust from the separation motors fogged the camera lens and made the rest of the video difficult to see.

Later, NASA announced that it was looking into a problem with explosive bolts that failed to fire properly during the launch. Immediately before the twin solid rocket boosters fired into life, only one set of pyrotechnics in ten explosive bolts exploded when commanded to do so. All 10 nuts exploded as planned, but NASA was interested in finding out an explanation for the unexpected anomaly.

Arguably the most significant event from this launch was the ET bipod ramp shedding a chunk of foam, estimated to be ~4"x5"x12", that broke away and hit the lower left SRB-ET Attach Ring near the Integrated Electronics Assembly (IEA) box causing a dent ~4" wide and 3" deep into the solid metal.[3] Prior to approval for the next mission, the situation was analyzed and NASA decided to press ahead under the justification that "The ET is safe to fly with no new concerns (and no added risk)" of further foam strikes. This fateful decision set the stage for the STS-107 tragedy just two launches later. The CAIB report did not highlight the significance of video data from this being the first flight with the ET Camera.