AHC: A better US space program WITH a shuttle

Look at this thread https://www.alternatehistory.com/forum/threads/wi-nasa-gets-the-flax-shuttle.325209/

You need a POD before January 5, 1972, the day Nixon approved the full size orbiter. There are all kind of shuttle concepts discussed there http://history.nasa.gov/SP-4221/ch8.htm

Yes! Reading the Flax Shuttle thread was one of the things that got me curious about alternate shuttles.

The table just above this link gives the expected development and launch costs of a Flax-style shuttle - development costs were only expected to be $800 million less (a saving of only 1/7th of the total development budget predicted for the full size TAOS shuttle). Costs/pound to LEO were expected to be double for the OMB shuttle. I wonder if both of those costs would have ballooned as much as the real shuttle's costs did? If they did, the OMB shuttle could turn out to be quite the turkey.

On the other side of the coin, if the costs turned out to be mostly accurate, the OMB shuttle could turn out to be an able and economical vehicle. NASA expected the smaller shuttle to be able to do 80% of the missions the full sized shuttle was expected to do - given the way the full size shuttle turned out to be more limited than expected, I expect the real comparison in capability would be that the OMB shuttle would turn out to be able to do 90-95% of what the OTL shuttle could actually do.

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The table just above this link gives the expected development and launch costs of a Flax-style shuttle - development costs were only expected to be $800 million less (a saving of only 1/7th of the total development budget predicted for the full size TAOS shuttle). Costs/pound to LEO were expected to be double for the OMB shuttle. I wonder if both of those costs would have ballooned as much as the real shuttle's costs did? If they did, the OMB shuttle could turn out to be quite the turkey.
I'm not sure if that total there includes LV development too. If this is about development costs of, e.g. TAOS-style designs with the given sizes, then that's different than the cost of taking a 10x30, 30,000 lbs capacity orbiter and sticking it on a cheaper LV concept. That doesn't appear to be limited to just the orbiter, which is relevant if you're talking about a totally different LV for it to fly on.
 
I'm not sure if that total there includes LV development too. If this is about development costs of, e.g. TAOS-style designs with the given sizes, then that's different than the cost of taking a 10x30, 30,000 lbs capacity orbiter and sticking it on a cheaper LV concept. That doesn't appear to be limited to just the orbiter, which is relevant if you're talking about a totally different LV for it to fly on.

That's a good point.

Either way, since (if memory serves) the OMB mini-shuttle was supposed to be launched on a Titan derived booster, replacing that with a fancy flyback booster and a LH2/LOX upper stage per Shevek's idea would probably raise the cost a bit.

On the other hand... Given that the full size shuttle was about 90 tonnes without main engines, and its payload was under 1/3rd of that, that would imply to me that a rocket-lifted mini shuttle able to lift 14 tonnes of payload would weigh in at something like 42-56 tonnes (probably towards the higher end, given that dry mass/payload goes up as you shrink a vehicle). I guess the OMB could push something like the Titan 3L4, which was anticipated to be able to lift 45 tonnes. I have the feeling that pushing the Titan hardware so far would turn out to be almost as expensive as designing new rockets with already available engines, since that's pretty much what they'd need to do to make the 3L4 booster anyway.

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Idea 2. could work, if payload bay is 10x60 ft and this Shuttle has the same payload capacity of a Titan 34D.
so NRO can bring there Satellite into polar orbit with this Shuttle.
That's 13500 kg into 160x270 km at 97° or 14305 kg into 160x270 km at 28°
with Transstage or IUS could this Shuttle launch 1843 kg into GEO. or lower mass for interplanetary mission.

but the main question is : can this Shuttle be cheaper als Titan 34D ?
 
That's a good point.

Either way, since (if memory serves) the OMB mini-shuttle was supposed to be launched on a Titan derived booster, replacing that with a fancy flyback booster and a LH2/LOX upper stage per Shevek's idea would probably raise the cost a bit.
The mini-shuttle there isn't the OMB glider as far as I see--it's smaller TAOS shuttles. This chart shows the difference: the glider was to be about 3 billion, but even the cheapest TAOS or partially expendable designs were in the >$4 billion range that all those numbers are in. And of course, that $3b does still involve the Titan III-L development costs.
 
The mini-shuttle there isn't the OMB glider as far as I see--it's smaller TAOS shuttles. This chart shows the difference: the glider was to be about 3 billion, but even the cheapest TAOS or partially expendable designs were in the >$4 billion range that all those numbers are in. And of course, that $3b does still involve the Titan III-L development costs.

That chart seems to be saying that the OMB glider would have a 12*40 foot cargo bay and a 30,000 lbl (14 tonne) payload capacity.

Of course, it occurs to me that the table that I linked to was produced by NASA - specifically Low and Fletcher. It is in the realm of possibility that the $4.9 billion development costs and $7 million operation costs mentioned in the table (for the 12*40 foot/14 tonne version) are over-estimates to make the under-estimates of the full-sized shuttle look good.

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Archibald

Banned
Surely enough, Fletcher and Low hated OMB shuttle proposals and Big Gemini, for that matter. I had to burn Fletcher at the OMB stake to have Low adopting the Big G.
Mathematica's Klaus Heiss had to kick NASA officials so that they adopted the TAOS as the cheaper full-size orbiter on hand.
Fletcher and Low by contrast placed all hopes in Mark I / Mark II Saturn Shuttle, with J-2 and ablative TPS for the start, later upgraded to ceramic and SSMEs. They were convinced they could prevail over Nixon OMB (which was a real PITA)

Interestingly enough, some of the shuttle concepts reviewed in 1971 had internal tankage for LOX while LH2 went into a drop tank.
Two things
a) Half of Philip Bono concepts (including ROMBUS) had similar tankage of internal LOX and external LH2. The reason is that LH2 is much more cumbersome than LOX.

b) Let's suppose for a minute that the shuttle orbiter stuck with internal LOX / external tank LH2. It would have tried and tested long term thermal cycling of the orbiter structure. Obviously the inner face of the tank would have to endure - 196°C while the outer side would be in contact with reentry very high temperatures of 1000°C ++. LOX however is much less dangerous than LH2 - what's left on the tank won't explode as gaseous hydrogen might.

There is another interesting aspect of internal LOX tankage. The large, empty tank would have made the orbiter "fluffy"(less denser) during reentry ; unlike OTL orbiter which sunk through the atmosphere like a rock, thermal loads may be lower, with some benefits for the ceramic tiles, who knows.
 
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So I was reading about European efforts to make a two-stage re-useable space plane, and it occurred to me that the Soviets, Europeans and Americans all started their efforts in this field by imagining a hyper-sonic carrier aircraft from which the orbital vehicle would launch. I wonder if starting with such ambitious ideas poisoned all the efforts, including the US effort. Perhaps, if NASA had started with the idea of launching the Shuttle on a fly-back rocket booster, rather than a persnickety hyper-sonic aircraft, fly-back rocket boosters would get the additional work they needed to be practical contenders in the US?

There is another interesting aspect of internal LOX tankage. The large, empty tank would have made the orbiter "fluffy"(less denser) during reentry ; unlike OTL orbiter which sunk through the atmosphere like a rock, thermal loads may be lower, with some benefits for the ceramic tiles, who knows.

Hmm. I wonder if residual LOX could be used as coolant (so the tank heats up, vaporizing the last LOX, which then gets vented, carrying heat away from the vehicle)?

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