ISS. Columbus laboratory is the largest single contribution to the ISS made by the European Space Agency (ESA). In May 2009 Atlantis flew a seven-member crew to the Hubble Space Telescope for its Servicing Mission 4, STS-125. The mission was a success, with the crew completing five spacewalks totalling 37 hours to install new cameras, batteries, a gyroscope and other components to the telescope. This was the final mission not to rendezvous with the ISS. The longest mission flown using Atlantis was STS-117, which lasted almost 14 days in June 2007. During STS-117, Atlantis crew added a new starboard truss segment and solar array pair (the S3/S4 truss), folded the P6 array in preparation for its relocation and performed four spacewalks. Atlantis was not equipped to take advantage of the Station-to-Shuttle Power Transfer System so missions could not be extended by making use of power provided by ISS. During the STS-129 post-flight interview on November 16, 2009, shuttle launch director Mike Leinbach said that Atlantis officially beat Space Shuttle Discovery for the record low amount of interim problem reports, with a total of just 54 listed since returning from STS-125. Leinbach added, "It is due to the team and the hardware processing. They just did a great job. The record will probably never be broken again in the history of the Space Shuttle Program, so congratulations to them." Leinbach made a similar report during a post-launch interview on May 14, 2010, saying that there were a total of 46 listed from STS-129 to STS-132. Orbiter maintenance down periods Atlantis went through two overhauls of scheduled orbiter maintenance down periods (OMDPs) during its operational history. Atlantis arrived at Palmdale, California in October 1992 for OMDP-1. During that visit 165 modifications were made over the next 20 months. These included the installation of a drag chute, new plumbing lines to configure the orbiter for extended duration, improved nose wheel steering, more than 800 new heat tiles and blankets, new insulation for main landing gear, and structural modifications to the airframe. On November 5, 1997, Atlantis again arrived at Palmdale for OMDP-2 which was completed on September 24, 1998. The 130 modifications carried out during OMDP-2 included glass cockpit displays, replacement of TACAN navigation with GPS and ISS airlock and docking installation. Several weight reduction modifications were performed on the orbiter including replacement of Advanced Flexible Reusable Surface Insulation (AFRSI) insulation blankets on