Heavy Lifting

I've been looking at NASA's proposal for a heavy-lift manned spacecraft for missions to the moon and Mars. Here is the pdf for those interested in such, my (completely underinformed) assessment follows.

http://www.nasa.gov/pdf/510449main_SLS_MPCV_90-day_Report.pdf

Okay, so. The gist of it is basically that Congress has given NASA a mandate and a $7-billion budget to create a space program capable of routinely carrying a crew and 70-100 ton payload to the moon and Mars (and if necessary the International Space Station, although this is a very secondary function), to be operational by 2016. It is not clear how many actual rockets Congress is envisioning, or if they are reusable or expendable, etc.

First off, for perspective, a single B-2 bomber costs about $1-billion, and adjusted for inflation a single Saturn V Apollo rocket would also cost about $1-billion.

Congress and the Obama administration gave NASA the green light to cannibalize as much of the space shuttle hardware and existing Constellation/Ares V hardware as possible. In many cases this is the same hardware; Constellation/Ares V was basically rebuilding Apollo out of spare space shuttle parts.

Respectfully to those far more knowledgeable than myself, building a moon or Mars vehicle out of spare parts from Low Earth Orbital vehicles seems like a fairly inefficient way to design a rocket.

I happen to own a 50cc 3hp scooter, which I enjoy a great deal on those rare occasions when it actually runs. It gets me around Seattle residential streets at about 30mph, and can do that at about 70mpg. If I wanted to build a 300hp truck to haul shipping containers from Seattle to New York, one way I could do that would be to use 100 scooter engines on a single cam shaft. And if all I had to build a truck with was old scooter parts, that's how I'd build a truck.

This is kind of what the Soviets did with N1, which was their answer to the Saturn V. They built four of them, and all four of them failed catastrophically. Which is kind of what you would expect from a truck built out of old scooter parts.

But then the Soviets built Proton, which was originally designed as an ICBM but was actually far too large for that task. After a bumpy start to the program, Proton proved (and continues to prove) to be one of the most successful heavy lift rockets ever built.

The American equivalents were and are the Atlas and Delta programs, with the Atlas V HLV and Delta IV Heavy being the current best heavy-lift rockets the US possesses, other than the remaining Atlantis space shuttle. Proton, Delta and Atlas have the advantage, like the Apollo rockets, of actually being designed from the ground up for long distance heavy lift.

It seems that Charlie Bolden is pushing to use the congressional mandate to create heavy-lift on-the-cheap as a means to restart the Constellation program under a different name. One salient point he makes in his report is that NASA had already looked at some 2000 different heavy-lift designs prior to Congress becoming involved in the discussion. With the implication that Constellation actually was the best and least expensive solution for heavy-lift, and if that's what Congress wants they need to get out of the way and actually fund it. Which is not entirely unreasonable, and a reasonable Congress might even be inclined to accommodate that. But the Congress we have right now, which does not want to fund disaster relief in Missouri and elsewhere because they have become so psychotically obsessed with the budget, isn't one which is going to hear that argument.

I happen to agree with Congress that learning from the Soviet "big dumb booster" concept is valuable, and can help NASA rethink its process of developing heavy-lift long distance space craft. But in doing so one needs to have a realistic understanding of what the Soviet program actually was able to accomplish, and how different the successful Soviet programs actually were from the US programs. Vostok, which epitomizes the BDB concept, was excellent but never intended for more than Low Earth Orbit. N1 was the biggest of the dumb boosters, but it didn't work. Proton worked splendidly, but could as well have been a US design.

What Bolden is basically saying is that to build a heavy-lift surfaced launched vehicle to reach the moon and Mars we need another Apollo, with Apollo funding. There is no time or money built into the congressional mandate for new R&D, so everything has to be accomplished with off-the-shelf parts. The Constellation/Orion MPCV capsule is already completed, so it's a no-brainer to use that. If we're insisting on leaving for Mars or the moon from earth's surface (as opposed to building and launching from the ISS) then duct-taping as many PBAN solid rocket boosters as needed to the outside of the main engines makes sense. The only remaining question is whether to use space shuttle main engines, Delta IV main engines or Atlas V main engines.

Either way, what you end up with is Constellation. By any other name.

Which, if it had simply been allowed to continue, over-budget and behind schedule as it was, still would have been completed earlier and cheaper than it will now, with all of this start/stop/start mess.

Because, at the end of the day, NASA has a much better understanding of what it takes to build a rocket than Congress does. Because being a politician isn't exactly rocket science.