Asri-unix.1310 net.space utzoo!decvax!cca!OTA@S1-A@sri-unix Fri Apr 23 23:01:27 1982 Some definitions of abbreviations From: Ted Anderson I was going to produce a glossary to help solve this and similar problems but somehow the project got delayed as might have been expected. In this case let me fill in the definitions for this case. OPF - Orbiter Processing Facility - This is the building at Kennedy where the orbiter goes after it returns from its landing and before it is remated to a new external tank (often refered to as an ET) and solid fuel rocket pair. OMS - Orbital Manuvering System - These are the small engines (using hydrazine as fuel and nitrogen tetroxide as oxidizer (this propellant combination is called hypergolic, this means that they ignite upon contact, no ignition system is needed (The ignition system is one of the hard parts about a liquid fuel rocket engine. It caused the failure of many early US rockets and probably Hudson's recent failure in Texas. The problem is that if you don't ignite the fuel immediately after it starts entering the combustion chamber it globs up in a kind of jelly (at least kerosene and LOX (Liquid Oxygen) do) which literally explodes when it does ignite.).) that the Space Shuttle uses for moving around in orbit. It also uses them to do the tail end of getting into orbit and for getting out of obrit before landing. SSME - Space Shuttle Main Engines - While I'm at it let me mention that this is the acronym that is commonly used for the big engines in the back of the orbiter that burn Liquid Hydrogen and Oxygen thats stored in the external tank. SRB - Solid Rocket Boosters - These are the solid fuel rocket engines that are straped onto the sides of the external tank for the first 2 minutes and 6 seconds of the flight. These burn a mixture of powdered aluminum and what amounts to "rubber". KSC - Kennedy Space Center - This of course is where the Shuttle is launched from. I hope these help, I may get around to the glossary project enentually. Ted Anderson ----------------------------------------------------------------- gopher://quux.org/ conversion by John Goerzen of http://communication.ucsd.edu/A-News/ This Usenet Oldnews Archive article may be copied and distributed freely, provided: 1. There is no money collected for the text(s) of the articles. 2. The following notice remains appended to each copy: The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996 Bruce Jones, Henry Spencer, David Wiseman.