
By National Aeronautics and Space Administration
The secure touchdown of STS-121 on July 17, 2006, marked the winning of entirety of NASA’s moment go back to Flight (RTF) venture. This ultimate version of NASA’s Implementation Plan for area trip go back to Flight and past presents an replace to NASA’s responses to the Columbia coincidence research Board innovations and observations, in addition to updates to the gap go back and forth application (SSP) “raising the bar” projects in the course of the RTF missions (STS-114 and STS-121). additionally incorporated is an replace to RTF-related bills throughout the finish of economic yr 2006. This ultimate variation presents technical updates that replicate the crowning glory and post-flight research of STS-121. those comprise NASA’s advancements to flooring and on-board ascent and on-orbit imagery features, alterations to the exterior Tank designed to minimize the ascent particles chance, and the turning out to be adulthood of NASA’s on-orbit thermal safeguard method (TPS) fix features. those updates describe how swapping out the 1st STS-114 exterior Tank, ET-120, resulted in a chance to research exterior Tank foam from a tank that had undergone an entire cryogenic loading cycle. This research resulted in a greater knowing of the basis reason mechanisms in the back of foam loss, and in particular ended in the removing of the protuberance air load (PAL) ramps from the exterior Tank for STS-121 and all next flights. STS-114 additionally supplied precious event and classes realized for fighting the free tile hole fillers noticeable on that flight. Following implementation of more advantageous methods to validate or substitute hole fillers, there have been no project affects from sticking out hole fillers on STS-121. a number of new functions have been additionally first verified on STS-121. New cameras with stronger viewing angles have been put in at the sturdy Rocket Boosters, offering engineers with higher assurance of the car in the course of ascent. The Orbiter growth Sensor System’s skill to function a good paintings platform for capability TPS maintenance used to be verified. A TPS fix fabric, non-oxide experimental adhesive (NOAX) was once effectively confirmed by means of astronauts in the course of an area stroll within the shipment bay, demonstrating that NOAX was once powerful in repairing small gouges and cracks in strengthened carbon-carbon fabric. eventually, a past due inspection of the TPS days ahead of re-entry was once additional to the venture timeline to examine the Orbiter for any major harm as a result of micrometeorite and orbital particles affects. including the consequences from STS-114, STS-121 succeeded in demonstrating the effectiveness of a few of the security advancements made to the distance travel approach in the course of RTF. NASA will proceed to pursue security advancements to the distance trip approach until eventually the deliberate retirement of the distance commute in 2010. advancements to the distance trip approach from STS-115 (the first foreign area Station meeting flight after RTF) onwards can be diligently reviewed and accounted for as a part of the traditional SSP and organization specifications and assets evaluation procedure. As we proceed to pursue rigorous engineering analyses throughout NASA, we're encouraging fit debate to spot, comprehend, and get rid of unacceptable threat that continues to be within the house go back and forth application. RTF isn't easily a suite of pursuits or pursuits, yet an evolution and development within the means we do enterprise. whereas we paintings to securely fly the distance commute, we're additionally operating to successfully transition these components which are appropriate to our destiny in exploration and stop these parts that might now not be wanted.