TABLE OF CONTENTS In the early days of space exploration, the problem of controlled atmospheric entry was as difficult and constraining as that of rocket propulsion itself. Although the technology is relatively mature and well understood today, it remains true that any Earth orbital mission for which the payload must be recovered, or any interplanetary mission targeted for a planet with an atmosphere, must address the issue of how to get down as well as how to get up. This obviously includes manned missions, and indeed some of the most challenging areas of manned spacecraft design are associated with systems and procedures for effective atmospheric entry.
It is worth noting that in several hundred missions over more than four decades of manned spaceflight, there has been only one fatal launch accident, the Challenger 51-L mission. Numerous launch abort procedures have evolved, and a variety of these (on-pad, in-flight, and abort-to-orbit) have been exercised in particular cases. In contrast, there have been three missions involving fatal reentry system failures of one kind or another (Soyuz 1, Soyuz 11, and Columbia STS-107), and several other "close calls." Though the technology of atmospheric entry is relatively mature, it remains very exacting in its demands, a characteristic deriving in part from the general lack of plausible abort scenarios following a primary system failure.
Atmospheric entry technology is a highly interdisciplinary area of space vehicle design. This is due to the many different functions that must be satisfied by the atmospheric entry system, and...
