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We could not build a Saturn V today; at least, not in the same way it was done in the Sixties. No, this isn't about the myth that the plans were deliberately destroyed. There's at least one complete set on microfilm, in the National Archives, and partial sets of paper plans exist in several locations. The people who drew those plans _knew_ they would be of historical interest (besides expecting them to be used much more than they were). The reason is that forty years have passed. Much of the infrastructure is simply gone. Recreating it would be prohibitively expensive.
Also prohibitively expensive would be doing things the way they were done then. The second stage intertank dome - the common bulkhead between the oxygen and hydrogen tanks - was a work of art, two segmented domes of aluminum with a fiberglass honeycomb between them. It had liquid oxygen on one side, and liquid hydrogen on the other, at different pressures and very different temperatures. It was stronger than a solid billet of aluminum the same mass, and far more insulating. For each one which was used, perhaps a dozen were rejected. The inspections were incredibly stringent, because the requirements could only be met by a perfect unit. They wound up creating what was essentially the world's largest surgical theater for the construction. Even then the failure rate was high, because a single speck of dust in a welded seam would make the unit unfit for service. And that was only one dome segment of two, and without the fiberglass honeycomb. Assembled units were tested by ultrasound. Some flaws could be repaired. For many of the other flaws some components could be salvaged. Some required scrapping everything.
This sort of process would be insanely expensive today. Fortunately, we now have better methods.
How reliable was the Saturn V? The first flight was a all-up; that is, the complete stack flew. It went all the way to orbit with no problems. There were minor equipment failures on other flights, but the payload always made it to space. During one Apollo launch the Saturn V was struck by lightning twice. The crew reset some breakers and kept going, the engines barely noticing. During the launch vehicle's total mission lifetime there were no serious failures, and very few minor ones.
Given economies of scale, it can actually be cheaper to design, test, build and launch a large rocket than a small one. This is something proponents of the Big Dumb Booster concept have known about for decades. The problem is that right now large payloads are few and far between... but that won't last.
When we do need to put lots of big loads into space something like a Saturn V would probably be a good choice. Even with that for our goal, we could do a far better job today than they did back in the Sixties... if we can just maintain the proper design philosophies. KISS is vital in this sort of work. So is knowing when to leave well enough alone. Any competent engineer knows there comes a time to say "That's good enough for now." As well as when something *isn't* good enough.
NASA is exactly the wrong agency for this kind of work. They don't just ask contractors to add unneeded bells and whistles, they _insist_ on having everything at least gold plated, if not made of solid platinum. The agency looks down its nose at anything which can do the job cheaply, feeling it isn't worthy of them. Just look at what they did to the DC-X. After the contractor met all program goals and came in on time and under budget with no major problems, they handed it over to NASA. Which promptly ignored everything the program should have taught them and tried to use it to test an expensive new fuel tank technology... and promptly crashed it.
There are companies working on cheap, simple launch vehicles. One is planning a launch later this month. When the time comes to put lots of tonnes into space, people like that will be ready and eager to fill the need. If we can keep the bureaucracy from sabotaging them.
Also prohibitively expensive would be doing things the way they were done then. The second stage intertank dome - the common bulkhead between the oxygen and hydrogen tanks - was a work of art, two segmented domes of aluminum with a fiberglass honeycomb between them. It had liquid oxygen on one side, and liquid hydrogen on the other, at different pressures and very different temperatures. It was stronger than a solid billet of aluminum the same mass, and far more insulating. For each one which was used, perhaps a dozen were rejected. The inspections were incredibly stringent, because the requirements could only be met by a perfect unit. They wound up creating what was essentially the world's largest surgical theater for the construction. Even then the failure rate was high, because a single speck of dust in a welded seam would make the unit unfit for service. And that was only one dome segment of two, and without the fiberglass honeycomb. Assembled units were tested by ultrasound. Some flaws could be repaired. For many of the other flaws some components could be salvaged. Some required scrapping everything.
This sort of process would be insanely expensive today. Fortunately, we now have better methods.
How reliable was the Saturn V? The first flight was a all-up; that is, the complete stack flew. It went all the way to orbit with no problems. There were minor equipment failures on other flights, but the payload always made it to space. During one Apollo launch the Saturn V was struck by lightning twice. The crew reset some breakers and kept going, the engines barely noticing. During the launch vehicle's total mission lifetime there were no serious failures, and very few minor ones.
Given economies of scale, it can actually be cheaper to design, test, build and launch a large rocket than a small one. This is something proponents of the Big Dumb Booster concept have known about for decades. The problem is that right now large payloads are few and far between... but that won't last.
When we do need to put lots of big loads into space something like a Saturn V would probably be a good choice. Even with that for our goal, we could do a far better job today than they did back in the Sixties... if we can just maintain the proper design philosophies. KISS is vital in this sort of work. So is knowing when to leave well enough alone. Any competent engineer knows there comes a time to say "That's good enough for now." As well as when something *isn't* good enough.
NASA is exactly the wrong agency for this kind of work. They don't just ask contractors to add unneeded bells and whistles, they _insist_ on having everything at least gold plated, if not made of solid platinum. The agency looks down its nose at anything which can do the job cheaply, feeling it isn't worthy of them. Just look at what they did to the DC-X. After the contractor met all program goals and came in on time and under budget with no major problems, they handed it over to NASA. Which promptly ignored everything the program should have taught them and tried to use it to test an expensive new fuel tank technology... and promptly crashed it.
There are companies working on cheap, simple launch vehicles. One is planning a launch later this month. When the time comes to put lots of tonnes into space, people like that will be ready and eager to fill the need. If we can keep the bureaucracy from sabotaging them.
