America's Space Shuttle: Return to Launch Site (RTLS) Abort NASA Astronaut Training Manual (RTLS 2102)

This unique and historic document provides extraordinary detail about the Space Shuttle's Return to Launch Site (RTLS) abort procedure. The official NASA astronaut training manuals comprised a major part of the formal flight crew training process, and were used by flight controllers as well. These internal NASA manuals were produced by the Mission Operations Directorate (Space Flight Training Division branch) at NASA's Johnson Space Center. The manuals and workbooks are extremely detailed and comprehensive, and are designed for self-study. A full listing of all acronyms and abbreviations used in the text is included. They provide a superb way to learn about Shuttle systems, hardware, and operational procedures. Special emphasis on crew interaction with the displays, controls, and hardware is included. If an engine fails during the first 4 minutes of ascent, the shuttle cannot achieve orbit. For the first 3 minutes or so of ascent, it cannot even reach a TAL. The only runway near enough to be reached is one near the launch site. In order to reach this runway, the shuttle must literally reverse course and fly back the way it came. The turn to reverse course is called powered pitcharound (PPA), and the timing of PPA is critically important. Since the orbiter is powerless once the main engines are shut down, these engines must be shut down when the orbiter has enough speed and altitude to glide to the runway. Also, in order to safely separate the orbiter from the ET, the ET should have no more than 2 percent propellant remaining. More propellant might slosh around and cause the tank to lurch and collide with the orbiter. Therefore, the shuttle must turn back toward the launch site at the exact instant that will allow it to arrive at MECO with the right amounts of speed, altitude, and propellant. If the RTLS is declared before the time of PPA, the shuttle has to perform what is called fuel wasting. This means pointing the shuttle more vertical (called lofting) to minimize loss of altitude while still flying away from the launch site and runway. This continues until the shuttle must execute PPA and turn back toward the launch site. From this point on, the shuttle thrusts back toward the runway until it reaches MECO conditions. These conditions are specified as 2 percent propellant remaining with the right speed, direction, and altitude to glide to a landing.