Posted on 11/06/2006 2:44:20 PM PST by blam
Y2K-like fears create shuttle scheduling crunch
22:07 06 November 2006
NewScientist.com news service
Kelly Young
The shuttle Discovery is being prepared for a December launch in the Vehicle Assembly Building at Florida's Kennedy Space Center (Image: NASA)
NASA hopes to get its next space shuttle off the launch pad and back on the ground by the end of 2006 in order to avoid the spectre of problems once ascribed to 'Y2K'. It is now considering moving the shuttle Discovery's planned lift-off ahead by one day, to 6 December.
The space shuttle's computer software is about 30 years old and does not recognise when the calendar year switches. On 1 January 2007, for example, it will think it is day 366 of 2006 a problem NASA calls 'year-end rollover'.
To reset the time, the shuttle's main computers would have to be 'reinitialised', which would mean a period without navigation updates or vehicle control, a situation NASA obviously wants to avoid.
NASA had already moved the shuttle's target launch date from 14 to 7 December in part to avert the year-end issue and in part to allow shuttle workers to rest over the holidays. Now, it is considering moving lift-off one day earlier, to 6 December, to give launch teams another chance to get the shuttle off the ground before the new year.
"It looks like we will not try to execute the flight over the year end," says NASA shuttle programme manager Wayne Hale. He points out that avoiding the calendar change is simply a long-standing recommendation rather than a requirement NASA may change the policy in the future.
Cutting it close
If the shuttle were to launch on the last day of its launch window, on 17 December...
(Excerpt) Read more at newscientistspace.com ...
Amen
My first real sysadmin job was for a DEC PDP 11/84
DEC 11/780... fond memories! What programming language?
Fond memories, indeed, sir. I was not on the programming staff so I can not speak intelligently to that question. In those days my job was keeping the hardware and VMS operating system working properly as I was employed by Digital Equipment Corp. at that time.
You are dating yourself "taxcontrol", good system though. My first with DEC was a TOPS 10 operating system running on a KI10 36 bit octal processor platform.
DEC had exceptionally good hardware. And the VMS OS was top notch. In 1986 or so I was the system manager of the first VAX Cluster in Kentucky. Four 11/780s. WOW, what a system (for the time :)
IMHO, if DEC could have gotten VMS to run on an Intel processor, I think DEC could have given Microsoft a run for it's money.
As long as we're being nostalgic, did you read "The Soul of a New Machine?"
Wow, you have been around and I am in good company here I see. :-) Actually DEC did build a VMS that would run on a LAPTOP back in 1995 but, as usual, they did not market it well. It was very expensive at $15k, a lot of money then and now.
I did not read "The soul of a New Machine" but I will certainly put it on my list....sounds like something I would enjoy...many thanks.
As someone who worked on both the IRS Y2K effort, and the Maryland State Treasurer's Office effort, I can tell you that no one in the banking industry got new computers. Banking transactions were ALWAYS transmitted using only the Julian day as the transaction date. There were two digit years in the headers, but within transactions actual dates were generated by windowing the Julian day in the transaction against the current Julian day in the computer. So any reports that the Banking industry was going to have trouble on Y2K were made by folks who didn't know anything about the system.
Actually the Shuttle has IBM 4PI computers. Architecturally they are a dual(that is 2) IBM 360s, thus the name "4PI".
AWACS uses a variant of the same computer, and that community refers to them as their "steam powered" computers. No lie.
No, the IBM 4-PI predates the Intel 386. It's even older than the 8086, IIRC.
No, yes, not sure don't think so, and yes.
Not on the shuttle itself. Ground based most likely. Here's a link showing the IBM System 4-Pi as the shuttle computer. It's been upgraded, but is still basically the same machine, just a little faster and with more memory. Also called the AP-101 in that application. AP-101S, the upgrade, replaced the core memory with semiconductor memory. (So I was slightly wrong above, but until that upgrade they did have "core")
Dang, and I was just guessing based on the Verdin system we had on the boats. :)
If I remember correctly, the 360 core RAM had hand wound coils; at least the early ones did.
If Burt Rutan was running NASA, I don't think this would be a problem. Has NASA never heard of software updates?
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