Jim Martin and his colleagues hoped the lander mission would follow the ideal schedule: Final prelaunch activities begin 56 days before launch with the terminal sterilization of the entire lander system within its bioshield. The craft must survive a 40-hour sterilization cycle, during which temperatures will reach a maximum of 112°C. During this preparation period, the lander is functionally passive except for its two mass-spectrometer ion pumps. Following a checkout, the propellants, pressurants, and flight software are loaded, and the lander is mated with the orbiter. After the first prelaunch checkout, initiated by the orbiter under local control of the guidance computer, the spacecraft is encapsulated, transported to the launch pad, and mated with the launch vehicle, followed by the second and final prelaunch checkout. All major communication with the lander before separation is accomplished through the orbiter communications link.
29 July |
Orbiter precountdown checkout and lander cruise-mode monitoring tests completed. |
30-31 July |
Lander computer prelaunch checkout. |
1 August |
Composite electrical readiness test completed. |
2 August |
Super Zip installed on Viking A shroud. (Super Zip is a linear explosive charge used to seperate the clamshell halves of the shroud after launch). |
3 August |
Pyrotechnic ordnance devices installed on Viking A. |
6-7 August |
Propellants loaded into Titan IIIE launch vehicle. |
*** The Titan IIIE core vehicle was shipped by C-5A aircraft from Denver, where it had been manufactured by Martin Marietta. The Centaur stage, built by General Dynamics Convair Division, was also flown to Florida on a C-5A from the factory in San Diego. United Technologies Chemical Systems Division shipped the solid rocket motors from Sunnyvale, California, by rail.