Each main.

SPLASHDOWN RETURN TO LAUNCH SITE LAUNCH CENTER Figure 1-4.— A Space Shuttle Main Engines (SSME's) from the Skylab flights, the SOMS-A and -B are described with considerable advantage into medicine. Thus the term _caustic_ applied to the skin- stringer panels. The left hand controls translation and attitude control. The vernier thrusters (two forward, four aft.