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I thought one of the records set for sustained human Gs was on a rocket sled... Ah yes, Dr. John Paul Stapp.

Ejection seats are another area where people are exposed to high Gs. The Gemini seats were particularly infamous. Both rocket escape systems and ejection seats balance the chance of injury to the crew against the risks of not getting them away fast enough.

Good stuff, as long as I only have to read about it :D

While an impressive vehicle, it's size is dwarfed by the Saturn V.

I called in sick to my job and flew down to Cape Kennedy to see the last launch of this monster. The last launch was used to put Skylab in orbit.

I got no closer than about Titusville, (I think this was about 10 miles from the launch pad) but when that sucker was lifting off, I felt a sonic impact that felt like someone slammed my chest!

All of the main engines on the three stages of the Saturn V, along with the main engine on the Service Module were mounted on gimbals, as are the three main engines on the Shuttles. I suppose the LEM used similar technology, but I don't feel like checking. Each of the RCS thrusters on the Service Module consisted of four nozzles at 90 angles. For Apollo geeks/modellers, here's a site absolutely loaded with detail shots of the Saturn V, including gimbals; http://www.apollosaturn.com/

Complicated is perhaps not the precise word I wanted. To plagerize two people more knowledgeable than myself:

It isn't the thrust that makes the SSME a piece of machinery running on the ragged edge of failure, but the chamber pressure. Give or take a bit, the RL-10 and the SSME have about the same thrust to weight ratio. However, the RL-10 was designed to operate only in space, where a high chamber pressure is not needed. It thus gets by with a low stress, expander cycle turbopump and a wimpy chamber pressure of about 30 atmospheres. The SSME was designed to operate in the atmosphere, and in order to avoid massive nozzle losses while doing so operates at a chamber pressure of about 200 atmospheres. This requires developing something like an order of magnitude more pump power for the same amount of weight. Not only are the turbopumps running at a massively higher stresses, the chamber is at about 7 times the pressure, increasing the amount of heat per unit wall area which needs to be dealt with. SSME development was a series of failure after failure, and NASA was so distrustful of the original turbopumps that it has spent massive sums on designing and building a completely new design of turbopump from another manufacturer.
It is chamber pressure, not thrust or size which makes an engine difficult to build. In turn, it is the SSTO requirement for the last bit of Isp and the requirement for operation in both the atmosphere and in space which drive the use of high chamber pressure engines.

--
Bruce Dunn

The development problems with the SSME were more a matter of tight funding and poor management... but they certainly were aggravated by the use of the staged-combustion cycle. The high pressures make the engineering more demanding and the failures more destructive, and the complex interactions between different subsystems make it difficult to debug them separately.
For example, the SSME start sequence is astonishingly complex, an elaborate dance of precisely-timed valve motions (with valves opening partway, pausing, closing slightly, pausing again, then opening wide), and as a friend of mine put it, "for every bend in those curves, there's a set of burned-out engine hardware to prove that it's necessary".
--
The space program reminds me | Henry Spencer henry@spsystems.net
of a government agency. -Jim Baen | (aka henry@zoo.toronto.edu)

You forgot to mention the Boost Protective Cover, or BPC. The BPC was part of the Launch Escape System (LES) which included the jettison motors. The BPC protected against heat buildup during launch and also protected the crew during a launch abort. They jettisoned the whole assembly around 270K feet. There's some really great footage kicking around of Apollo 6 losing its BPC as viewed from the inside of the cabin.

With all due respect, the Saturn-V rockets on display around the country never flew or participated in the actual missions to the Moon. The closest any of them actually came to a flight was the 1st stage on display at Kennedy - it was the test-firing engineering mule and was at least lit-up. Check this link for what IS actually on display. This tower is the last thing fixed to the ground which Neil Armstrong stood upon before getting into his tiny Apollo capsule (the only real bit of that rocket which we recovered). This tower is the last part of real flight-related Apollo hardware which could be restored to the quality it was in for that historic flight. That's why its important. Virtually nothing of the REAL Apollo hardware exists any more. Apart from anything else I am working with the teams behind the Saturn-V restoration efforts at Johnson and Marshall Space Centers and we are sharing resources. If we can find the money for this project it will be simple to find the relatively small amount required for those projects too.

Actually the Saturn V was the largest operational rocket ever.

Is worth a stop if you're going through TX. They've got a visitor center which is sort of an annoying combination of Disneyworld meets dumbed-down NASA, but the tours of the actual mission control center and such are quite cool. Also the Neutral Boyancy Lab is a blast. On the lawn out front they've got a Redstone rocket with a Mercury capsule up top, and also a Saturn V which is truly spectacular to walk beside (the various pieces would've been Apollo 18-20 but for the project cancellation).

Can you come up with a better way to get humans into space (and bring them back if needed)?

I don't have to. Someone else already did that.

Everything you've ever wanted to know about the Saturn V.

A Google search found this site. It lists all the commands and has an ASCII drawing of the display.