...isn't the shuttle navigation powered by something similar to a 386 from intel?

The shuttle orbiter uses the IBM AP101S, the latest revision of the original AP101. It is a general-purpose computer provided in packaging suitable for aerospace physical requirements. Its architecture and instruction set are similar to the IBM System/360 commercial mainframe.

The computer design for the orbiter was remarkably thoughtful. A lot of special-purpose hardware was built to offload mundane computing tasks like I/O management. The engine controllers, for example, are dual Honeywell HDC-601 systems in a failover configuration.

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"Facts are stubborn things." --John Adams
Clavius Moon Base

ah yes, comparable to a 386 or relatively so at least...

i found an interesting article about it (they use several AP-101S parts, btw) and it contains one simple statement that puts the whole thing in persepective:

linky here...

taks

well, I'm not 100% sure, but I think our education was worse. I've read studies, after all, but then again, I've not read studies from 40 years ago testing the same thing. can someone older than I tell me what it was like to be bookish in the 60s?

it is true, however, that quite a lot of it seems to be proliferation. the internet is a tool. like all tools, it can be used for positive or negative purposes. BABB (and the website attached to this board) are positive. all those bloody sites about the hoax, or conspiracy theory du jour, are negative. the problems arise when the negative uses predominate.

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Gillian

"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"

"You can't erase icing."

"I can't believe it doesn't work! I found it on the internet, man!"

maybe not so much worse 40 years ago as it was less advanced... i'd be willing to bet there weren't many high schools teaching calculus in 1960, yet i managed college credit for it in 1986 as a senior (ut oh, dating myself).

the focus of education was certainly different, as societal viewpoints were different then as well... that's a constant evolution, however, with each new generation of parents i suppose.

taks

Reliability is far preferable to speed and capacity. The computational problems for space flight are not especially problematic until you are confronted with numerical solutions to orbital mechanics problems. That is a strategic application, not a tactical one. But regardless of what particular technology you choose for a control system, it becomes a critical component and must be engineered as such.

Not only must a system perform to specification for a longer time and with greater reliance, it must usually do so in a hostile environment. Space engineering is fraught with thermodynamic, electromagnetic, radiation, mechanical, and vibrational factors that affect system reliability. Acoustic loading is heinous, especially with engine controllers that are physically mounted to the engine structure. Rocket engines can generate something like 20g in acoustic loads.

People are always fond of telling me how much more power their PDA has than a space shuttle or Apollo guidance computer. I tell them that we should really put them to a more evenly-matched test. Let me boil their PDA and then put it in a paint mixer while I cycle its power two times a second. We'll see how well it computes during that. And I get to kill them if their PDA malfunctions. For man-rated space applications I'll take a slow, clunky dinosaur any day over a lump of chastised, nonfunctional consumer silicon.

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"Facts are stubborn things." --John Adams
Clavius Moon Base

=D>

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At night the stars put on a show for free (Carole King)

One Earth, One Sky - IYA 2009

Hay! i not dummer...
[-(

Ditto - =D>

That's hysterical!

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"I'd take the awe of understanding over the awe of ignorance any day." - Douglas Adams

I just want to add myself as someone in his early twenties (23) that has no doubts about Apollo, or the Holocaust, or that the government isn't evil.

Though I am a bit biased seeing as I grew up right next to Washington D.C. and have several relatives including my Dad, and parents of friends, that work or have worked for the government at one point or another. It gives you a much less suspicious view of government.

Is there any reliable data about the prevalence of hoax beliefs among different age groups, or the distribution of ages among HBs and believers in other common conspiracy theories?

I've found some references to a 1999 Gallup poll that found about 6% of respondents believed that the Moon landings were faked, but the poll itself is no longer on the Gallup Web site and any demographic data it contained has gone with it.

I'm sure we've all got anecdotes and impressions, but what do we actually know about the subject?

doubtful...
taks

seems like anecdotal evidence to me. then again, I don't do much debunking. Jay, do you know the ages of the people who you enlighten on the subject?

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Gillian

"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"

"You can't erase icing."

"I can't believe it doesn't work! I found it on the internet, man!"

No, I generally don't deal with age.

__________________
"Facts are stubborn things." --John Adams
Clavius Moon Base

it would seem to reason that believers would tend to be younger, simply due to a lack of experience and/or education. however, i think experience in this case is a double-edged sword creating the very distrust that breeds conspiracy. such beliefs tend to override logic and common sense, too.

taks