They didn't fly it without testing--it was the test that was wrong, due to a null corrector that wasn't positioned correctly. They just didn't double-check it--the redundant test was cancelled due to budget constraints.
Cheers
Phil Hobbs
The Lord had a few things to say about folks like you.
True, but the whole structure was fragile. It was hot because it had wings. It had wings because they wanted it to look like an airliner. The o-rings, the foam, the fragile materials were all bad design decisions.
The design was a horrible kluge, for cosmetic and political reasons. Some very good people died at no advantage. The shuttles and the ISS will be retired soon, having accomplished pretty much nothing. There's not much for people to do in LEO but try to stay alive, and the stars are out of reach.
The ISS *could* be a hot-standby storage space for a flock of comet/asteroid defense missiles, and we *could* have a fleet of small telescopes in orbit looking for planet killers.
John
How many years of development do you think the mobile tracking Ku band antenna they just mounted on the Space Station had? How many jobs were involved with its development? How many jobs were there making it able to operate in a space environment? What about the modems and other equipment that it also required to operate?
They used a single, bad fixture to check it. P&E never did basic testing or imaging because they decided that the mirror was so good, other tests weren't up to their standards. Some simple tests would have shown the gross error. The backup mirror, made by Kodak, was properly tested. I think it's still in a crate somewhere. They has two mirrors and didn't test them to see which was the best.
You've got to stay paranoid when building complex stuff. Looking away from possible problems is trouble.
John
What use were those jobs? You may as well pay people to dig holes and other people to fill them. Makework is a waste to society.
And why did they just add an expensive antenna to a heap that will burn up on reentry in a few years?
John
Why? You'll just pull a dimbulb and deny it.
They bought from where I worked too. For well over 30 years. Some of my ideas are in products they are using, and they spent millions of dollars on our equipment. Some was in continuous use for over 30 years, other than a couple short power outages when labs were rewired. It was still in calibration, and never required any repairs.
When it is time to deorbit ISS, apparently into the satellite graveyard in South Pacific, but what happens, if the controlled deorbit system fails ?
Large objects can fall down anywhere between 52 N and 52 S, which include nearly all high population density areas in the world.
Now you are being completely unfair to NASA. It was as good as they could make it with the materials and technology available at the time.
Its routine Shuttle bus image was sort of true in that you could put mission specialists to do experiments in space on board without quite so much heavyweight astronaut training. But space exploration is always going to be very dangerous. The energetics to reach escape velocity are serious stuff. And correspondingly coming back down you have to get the right trajectory - too shallow and you skip off like a stone from a pond and too steep and you burn up on re-entry.
The Shuttle was designed to land at an airfield instead of requiring a splashdown and sea rescue like Apollo. That was a good decision.
Putting missiles into space unless we absolutely have to is a very dangerous escalation of the militarisation of space.
There are plenty of ground based survey scopes looking for and cataloguing small asteroids and comets. SOHO images are popular with amateurs looking for sun grazing comets so even the terrestrial blind spot is fairly well covered. It is rare these days for a Comet to bear a human discoveres name the survey instruments hoover them up first.
The names are much less romantic (hardware used in brackets).
Regards, Martin Brown
When the Apollo moon missions were launched a human crew was the only way to do it. It is only comparatively recently that robotic probes have become sophisticated enough to do flexible missions. During Apollo portable calculators were developed to give them a sporting chance of computing a return trajectory if the main computer failed.
Space exploration is intrinsically dangerous. It is a *very* hostile environment for life outside of the Earth's atmosphere. We should not be surprised when some of them do not come back safely. There are still enough volunteers to satisfy the requirements for astronauts.
I favour robotic exploration whenever possible unless and until we find something that the robots cannot do and a bloke working in a clumsy pressure suit can. These are increasingly rare now as robots have become pretty dextrous and kit can be designed to make it easier for robots to work with them. Witness the Mars rovers longevity.
Regards, Martin Brown
Only the *very* best amateur mirror makers could hope spot zonal errors on an R-C primary mirror. There is good reason why R-C designs are not commonly mass produced. SCTs are a simpler design and also beyond most amateurs to make. Amateurs typically make almost spherical mirrors and then parabolise them.
It isn't true to say that P-E didn't test it either. They did but discounted as inaccurate the results that conflicted with the their ultra precise (but incorrectly assembled) null corrector.
These days at least one other completely independent method is used to check exotic mirror figures - holographic techniques. But the computational power to do that was not available then.eg the MMT
And the other tests that were done did show what was with hindsight the error as present but were discounted because they lacked precision. See the summary on p4-7 in
Actually they did test them and chose the one with the best surface roughness which was the P-E mirror. It was made very very precisely but unfortunately to the wrong shape template.
When the budget was in danger of the whole thing being cancelled they could not afford the luxury of a full system test. The crazy thing was that they did not build a brace of HSTs since the additional cost to build the second one was tiny compared to the total design investment.
The Kodak mirror is now a door stop at the Smithsonian Air & Space Museum which is a heck of a waste of a space qualified mirror.
Regards, Martin Brown
While direct industry subsidies are not accepted e.g. by the WTO, it is a common practice all over he world to use such projects to direct state money to company R&D in their own country, so that the companies can later on generate new commercial products based on the R&D done to such special projects. In addition, engineers working on the project will gain skills that they can use later in life to create better products.
Such projects are a more or less internationally accepted method of giving subsidies to the own industry.
If the contracts go to companies that only produce products to the national space administration and the engineers work for these companies until retirement, then it could be compared to digging and filling holes.
One interesting point in that criticism was the high inclination orbit.
Without it, Baikonur in Kazakhstan could not have been used to launch ISS modules. After US Shuttle retirement, there would be no ways to send new crews to ISS, since the Soyuz space crafts are also launched from Baikonur.
While a Soyuz (A-series) launch site is still under construction in Kourou in French Guiana, which could reach a low inclination orbit, but I have never heard of any attempts to man-rate that launch site.
On a sunny day (Fri, 28 May 2010 09:40:17 +0100) it happened Martin Brown wrote in :
We need to spot a nice habitable planet. So we can drill for oil there and pollute it.
On a sunny day (Thu, 27 May 2010 19:51:32 -0700 (PDT)) it happened George Herold wrote in :
You are right of course, but what I was sort of jokingly pointing out is: That once you have reached the status of 'astronut', that basically means you have been a few hundred miles? up, then you are safe and have the safest job, a PR job basically.
While LH/LO upper stages (GTO/planetary) was not accepted after Challenger, why would man rating increase the cost of satellites that did not contain flammable or toxic substances ? Some vibration tests ?
Some critics also claim that the USAF original requirements forced some stupid design decisions and I fully agree with those critics.
STS at LEO is about 100 tons, while Saturn V was 130 tons, as expected. Unfortunately the STS actual net payload (ISS modules etc) to orbit is these days about 10 tons.
A much more sensible approach would have been a small 10-20 ton space plane with 2-8 seats, a non-reusable payload bay (perhaps 80 ton net load) or alternatively a smaller payload bay and a much smaller lift of mass.
The Earth rotates 15 degrees each hour and one orbit takes 90-120 minutes, so the Earth has moved up to 30 degrees below the orbit. Situation gets nasty especially on the intended polar orbits, so up to
2000 km aerodynamical flight sideways is required, which require large wings.Without such sideway requirement, wingless crafts could be used, saving in wing heat shields, wing weight and avoiding the Columbia type disaster.
It had wings because the requirement was landing back to the runway of the launch site after only a single orbit.
If the requirement would have been landing on a specific airstrip every 24 h, then the wingless HL-10 would have been sufficient.
If the space program had continued with any sort of shielding, the odds are high that someone would have died. It is a very dangerous thing to do. The main problem in the shuttle design is that it is positioned so that ice falling off the tank can hit it.
Based on what I have heard, the whole rocket motors and external tank thing are the results of budget cuts and politics. The Rocket motors are in sections because they need to be made in Utah for political reasons. The re-rounding and reusing of the solid rocket motors was more about being able to say "reused" than saving money.
From what I heard, the whole launch system was completely different and the shuttle wings had the ability to get longer once they got down to about 300 MPH. Budget just wouldn't allow it so the shuttle ended up only able to get to low orbits.
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I suspect you are right. We have worked with some of the NASA science types. Many of them really know their stuff. A few were very concerned about the paper work being signed. Our guy wisely just said "no" to signing any paper work that was brought along at the last minute and suddenly the extra paper work went away and the science guys took charge.
Isn't that a little like tricks on the blind?
Fit it with high explosives so that it gets broken up after it is low enough that even the fastest bits will reenter nearby. If it comes in wrong, few big bits will be left.
one may get inhabitable.
rm,
Lots of folks have worked on platforms. It is actually a surprisingly safe way to make a living. Your risks are much higher if you run a family farm.
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