First, its important to understand what the Ares I rocket is (and isn’t)

Ares I consists (from the top down) consists of, at the top, the launch abort system (the long pointy thing at the top). Below that is the Orion Capsule/Service Module. Under that is the 2nd stage, which uses what is called a J-2X engine. Below that the 1st stage, which consists of a 5 segment rocket, based on the 4 segment Solid Rocket Booster on the shuttle (the 2 things on the side of the shuttle, when it launches), although the propellant grain and burn is different. Also, if memory serves me correctly, the guidance systems that were planned for Ares I are still under discussion, and might be largely handled by the Orion spacecraft.

The Ares I-X rocket consisted of a mass simulator of the LAS & Orion Spacecraft, a Mass simulator of the 2nd stage, a mass simulator of a single segment of the SRB, and a modified 4 segment shuttle SRB. In addition, the guidance system was a modified Atlas V guidance system.

In other words, the top was different, the 2nd stage was different, the first stage was different, and the guidance system was different. Now, I have no problem doing test flights – I think they are great things, and its important to remember they are tests. But, for test flights to be valuable, they need to test the actual flight hardware

The first computer I worked on was the Univac 1108(1969), which was sold as a third generation machine [1)tubes,2) transistors,3) integrated circuits] though it was really only generation 2.5. Most of that computer was transistors, resistors, capacitors, inductors. Only the registers (with 177 base 8 addresses) were integrated circuits.

The military had, at the same time, the YUK 7(a mil-spec, hardened Univac 1108), which, as I recall, used all integrated circuits and was 1/10th the physical size of the Univac 1108.

I’m pretty sure the onboard computers on Apollo were similar to the U 1108, a mix of solid state and integrated circuits.

Russian satellites used tubes in those days, which proved much more reliable than solid state devices in hard vacuum, since vacuum evaporation of printed circuits and redeposition of conductive thin films was a real problem. We eventually solved that problem and now integrated circuits are much more reliable than vacuum tubes in the same environment.

GAry 7

I’m curious if Phil has any more information on what he said about the Ares I-X launch being basically a sham.

The exploration part of the manned space program should focus on direct trips to Mars and maybe a landing or orbit of a near-earth asteroid. (Doing this will also help us get a lot closer to doing the moon colony.)

1. Prof. Park has addressed the issue of a Chinese expedition on to the moon his web site and his response is “yawn”.

2. The argument for human space flight seems to come down to a spirit of adventure and exploration, much like Columbus, Magellan, and their contemporaries. That’s all well and good, but in these times of massive budget deficits, this is an adventure that we can’t afford, particularly as it will detract from scientific discovery from robotic missions which will have to survive on short rations.

However, let me state the case this way. Returning to the moon with astronauts is a big so what. We did it 40 years ago with far inferior technology. I think that a far more exciting discovery is potentially within reach with present technology, namely the possibility of life in the oceans of Europa. Imagine a robotic mission to Europa in which a TV camera or other such device is lowered into one of the vents in the ice sheet and discovers a shark (or other living creature) swimming around in the Europaen ocean. That would, IMHO, be the greatest discovery in the history of the human race.