yee@trident.arc.nasa.gov (Peter E. Yee) (10/12/89)
KSC SPACE SHUTTLE PROCESSING REPORT - WEDNESDAY, OCT. 11, 1989
STS-34 - ATLANTIS (OV 104) - PAD 39-B
Workers have opened up the orbiter's aft compartment and
will be setting up special platforms on the mobile launcher
platform to allow removal of the controller from main engine
number 2. Schedulers are assessing a new launch date.
Today, workers will continue setting up access platforms and
begin removing heat shields surrounding the number two engine.
Once the access has been set up and the heat shields have been
removed, the engine will be positioned to allow removal of the
controller. Rocketdyne technicians are scheduled to begin
disconnecting the controller today. There are about two dozen
connections between the controller and engine.
Once the new controller has been installed, a flight
readiness test, which involves cycling engine valves and
actuators, will be conducted to verify the operation of the
controller. The controller weighs about 230 pounds and is an
electronic package that controls all main engine components and
operations. The dimensions of the controller are 23 X 14 X 7
inches.
After the successful retest of the controller, workers will
button up the aft compartment and remove access stands prior to
the resumption of the launch countdown.
Only work necessary to change the controller is planned at
the launch pad until the countdown resumes. The STS-34 countdown
will remain in an indefinite hold at the T minus 19 hour mark.
The countdown entered the second planned built-in hold last night
at 4 p.m. at the T minus 19 hour mark.
Yesterday, the launch team successfully completed loading
the power reactant storage and distribution system with the
liquid hydrogen and liquid oxygen reactants. Console operators
will monitor this system from the firing room.
The STS-34 five-member flight crew left the Kennedy Space
Center this morning. They will return to Houston and practice
launch, entry and Galileo deploy simulations in the shuttle
simulator. The crew will return to KSC several days prior to the
launch.johnson@ncrcce.StPaul.NCR.COM (Wayne D. T. Johnson) (10/12/89)
In article <33403@ames.arc.nasa.gov> yee@trident.arc.nasa.gov (Peter E. Yee) writes: > controller. The controller weighs about 230 pounds and is an > electronic package that controls all main engine components and > operations. The dimensions of the controller are 23 X 14 X 7 > inches. Hmmm. Thats about the size of a PC. And it weighs 230 pounds? On what planet did they weigh this? Or is it using lead instead of silicon in its chips. On second thought, its probably descreet transistors mounted on cement PC boards. No wonder the shuttles so heavy. -- Wayne Johnson (Voice) 612-638-7665 NCR Comten, Inc. (E-MAIL) W.Johnson@StPaul.NCR.COM or Roseville MN 55113 johnson@c10sd1.StPaul.NCR.COM These opinions (or spelling) do not necessarily reflect those of NCR Comten.
henry@utzoo.uucp (Henry Spencer) (10/13/89)
In article <1621@ncrcce.StPaul.NCR.COM> johnson@ncrcce.StPaul.NCR.COM (Wayne D. T. Johnson) writes: >> ...The controller weighs about 230 pounds ... > >Hmmm. Thats about the size of a PC. And it weighs 230 pounds? On what >planet did they weigh this? Or is it using lead instead of silicon in its >chips... Uh, this thing is bolted to an SSME. The turbines that drive the *pumps* on an SSME are rated at over 80,000 horsepower. The SSME itself puts out roughly as much power as a *really huge* power plant, in an assembly a few feet across, burning half a ton of fuel per second at a pressure higher than that in a compressed-gas cylinder. The noise alone is capable of doing serious damage to nearby equipment. You had better believe that the engine controller, which is required to be essentially 100% reliable, is built just a wee bit more sturdily than your tinplate-and-plastic PC. -- A bit of tolerance is worth a | Henry Spencer at U of Toronto Zoology megabyte of flaming. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
john@frog.UUCP (John Woods) (10/16/89)
In article <1621@ncrcce.StPaul.NCR.COM>, johnson@ncrcce.StPaul.NCR.COM (Wayne D. T. Johnson) writes: > In article <33403@ames.arc.nasa.gov> yee@trident.arc.nasa.gov (Peter E. Yee) writes: > > controller. The controller weighs about 230 pounds and is an > > electronic package that controls all main engine components and > > operations. The dimensions of the controller are 23 X 14 X 7inches. > Hmmm. Thats about the size of a PC. And it weighs 230 pounds? On what > planet did they weigh this? Or is it using lead instead of silicon in its > chips. On second thought, its probably descreet transistors mounted on > cement PC boards. Though it probably is made from bulkier, heaver technology than a typical PC, it probably owes a good fraction of its weight to being in a thick, iron box which is EMI proof. Unlike a typical PC user, NASA probably cares whether or not the engine computers crash when a nearby radio transmits... -- John Woods, Charles River Data Systems, Framingham MA 508-626-1101 ...!decvax!frog!john, john@frog.UUCP, ...!mit-eddie!jfw, jfw@eddie.mit.edu