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Was directed to GCNR about you.

He (gaetanomarano) is...

I haven't really done much research (as you can probably tell), but I'm learning fast. I think I briefly skimmed over some chat in the nasaspaceflight forums which mentioned that 'The Stick' won't be good enough to lift the Orion. That's the only source I remember. Frankly, I'm surprised at my current 'hit score' considering the next-to-nothing research I have actually done.

Nevertheless, at the very least, I hope to promote discussion and thought, just in case there is some room for improvement somewhere...

With that said, I'll continue: What is this toxic vapor related to the ammonium perchlorate that the wikipedia article mentions? I wasn't able to find any more info on it. Edit: Is it just unburned perchlorate?

BTW, while you may be a bit biased, I appreciate your vast and detailed knowledge. I guess we need realists like you to bring dreamers like me back to earth. However, dreamers have been right in the past. Perhaps the idea is to be able to seperate the potentially viable dreams from the pure fantasies...

Yeah, your right. Also, it won't be good when it re-enters uncontrolled after its been neglected in orbit. Case closed.

Just a quick thought: has anyone ever considered retiring the shuttle orbiters in space. That is, non-return space missions to the ISS instead of decomissioning them. I'm sure they'll make useful additions to the space station, especially if fitted out with pressurized cargo bays, although they might not be worth the safety concerns. Still, could be a fitting tribute to the orbiters.

Here's another idea: Use the current Shuttle ET's in a Paris VII configuration. By my calculations, such a vehicle at its skinniest will just fit through the VAB door with about an inch either side...

Actually, a Paris V configuration would just fit through also.

Now let it be clear: I don't care much myself about the environmental effects of a shuttle launch. I don't recycle, I drive a gas-guzzling sports car, and well, generally I don't care much for the environment. However, that is not to say that the environmental effects of a shuttle launch won't play a negative part in the future. In other words, I'm afraid that the greenies will give NASA bad PR, whether they deserve it or not.

Whether you like greenies or not doesn't matter.

"The chemistry of the solid rocket booster propellant can be summed up in this reaction:"

From Wikipedia articles:

The propellant mixture in each SRB motor consists of ammonium perchlorate (oxidizer, 69.6% by weight), aluminum (fuel, 16%), iron oxide (a catalyst, 0.4%), a polymer (such as PBAN or HTPB, a binder that holds the mixture together, also acting as secondary fuel, 12.04%), and an epoxy curing agent (1.96%).

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Ammonium perchlorate is a chemical compound with the formula NH4ClO4. It is the salt of ammonia and perchloric acid. Like other perchlorates, it is a powerful oxidizer.

This salt generates toxic gas and extremely high temperature elevation following its decomposition.

Like all ammonium salts, it decomposes before fusion. Mild heating results in chlorine, nitrogen, oxygen and water, while strong heating may lead to explosions.

It is an important oxidizer used in solid rocket propellants, such as the Space Shuttle Solid Rocket Boosters, as well as many other solid rockets including some fireworks, amateur and hobby high powered rockets, and larger rockets used for space launch and military purposes.

The PEPCON disaster happened at an ammonium perchlorate manufacturing plant. The resulting explosions measured 3.5 on the Richter scale

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Aluminium is a neurotoxin that alters the function of the blood-brain barrier.[11] It is one of the few abundant elements that appears to have no beneficial function to living cells. A small percent of people are allergic to it — they experience contact dermatitis from any form of it: an itchy rash from using styptic or antiperspirant products, digestive disorders and inability to absorb nutrients from eating food cooked in aluminium pans, and vomiting and other symptoms of poisoning from ingesting such products as Rolaids, Amphojel, and Maalox (antacids). In other people, aluminium is not considered as toxic as heavy metals, but there is evidence of some toxicity if it is consumed in excessive amounts. The use of aluminium cookware, popular because of its corrosion resistance and good heat conduction, has not been shown to lead to aluminium toxicity in general. Excessive consumption of antacids containing aluminium compounds and excessive use of aluminium-containing antiperspirants are more likely causes of toxicity. In research published in the Journal of Applied Toxicology, Dr. Philippa D. Darby of the University of Reading has shown that aluminium salts increase estrogen-related gene expression in human breast cancer cells grown in the laboratory. These salts' estrogen-like effects have lead to their classification as a metalloestrogen.

It has been suggested that aluminium is a cause of Alzheimer's disease, as some brain plaques have been found to contain the metal. Research in this area has been inconclusive; aluminium accumulation may be a consequence of the Alzheimer's damage, not the cause. In any event, if there is any toxicity of aluminium it must be via a very specific mechanism, since total human exposure to the element in the form of naturally occurring clay in soil and dust is enormously large over a lifetime.[12],[13]

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PBAN - Polybutadiene Acrylonitrile copolymer. Also noted as Polybutadiene — Acrylic acid — Acrylonitrile terpolymer.

This was the binder formulation widely used on the 1960-70's big boosters (e.g., Titan III and Space Shuttle SRBs). It is also sometimes used by amateurs due to simplicity, very low cost, and lower toxicity than the more common HTPB. HTPB uses isocyanates for curing, which are generally toxic.

PBAN is normally cured with the addition of an epoxy resin, taking several days at elevated temperatures to cure.

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The reactivity of isocyanates makes them harmful to living tissue. They are toxic and are known to cause asthma in humans, both through inhalation exposure and dermal contact. Exposure to isocyanates and their vapors should be avoided.

I sincerely hope you are right. I hate the shuttle and ISS just as much as you do. However, I cannot say whether NASA will ever be sufficiently pardoned from either before 2020.

But your right. IMO, NASA is stuck between a rock and a hard place with this one.

These are problems with the Shuttle system only. I doubt whether anyone will care when woody woodpecker takes a bite out of Ares V's delicious foam.

In the environmentally conscious world of 2020, SRB's just won't work.

Okay, here's my latest plan: First, don't waste effort with 'The Stick' and these problematic 5-segment SRB's. Instead, build a direct orbiter replacement based on the Shuttle-C, with an Orion on top and two RS-68's as described in a nearby thread. Then, while the ISS is finished, and the Orion is being tested, forget the Ares V and jump straight to this vehicle:

Ares VI:

- A pair of 4-segment SRB's, like the shuttle.

- A suitably reinforced 10m diameter tank, as tall as can fit under the VAB doors with an upper stage and payload.

- An engine cluster of 6 or 7 standard RS-68's or RS-68b's.

The dry weight will amount to 590 + 590 + 118 + maybe 160 tonnes payload = ~1500 tonnes max. This is less than the Ares V with its pair of 5-seg SRB's (SRB's suck, remember).

Then, once you've got this, develop the core a little further to allow for Paris III's and VII's.

Artwork will follow shortly.

Edit: This Ares VI will probably lift about the same as Ares V. This is because the larger main tank will probably barely make up for the smaller SRB's. Can anyone confirm this?

I'd have to say I prefer a Direct Shuttle Derivative (DSD or DIRECT) over the Ares I ('The Stick'). http://www.directlauncher.com/ It's quicker, cheaper, safer, and more versatile. However, if we go down this route, we may still need to develop an Ares V style vehicle for proper lunar and mars missions. Therefore, it might be better to revive an even cheaper option than DIRECT for the interem: A crewed version of Shuttle-C. Here's my proposal: mount a 'compromise Orion' capsule atop the expendable side mounted pod. Have the module sit near where the entry hatch is now on the shuttle, and power the pod with two cheap standard RS-68's.

This vehicle will be a direct 'Orbiter Replacement': It shouldn't require any noticeable changes to infrastructure at all. This design will be the cheapest possible to develop; I don't see where you could cut costs further with this one (except if you use a cluster of 3 SSME's, but the increased launch costs won't be worth it). The payload might be only 70 tonnes or less (due to the less efficient RS-68's), but with the weight of the Orion, this will still leave more payload than what can fit in a Shuttle bay.

Again, has this or similar design been discussed in any detail before? Forgive me if it has.