“It seemed like a good idea at the time” is probably the single biggest flagstone the road to Hell is paved with.
The problem is that post 1972 congress and the taxpaying public simply didn’t want to pay for an ambitious space program. Apollo got its start in the early 1960’s when it was presumed that manned spaceflight would have an immediate and important role in the strategic balance between the US and the USSR. We would never have gone to the moon without the “Space Race”; and once it became clear that nobody was going to base nukes in space or nationalize the moon or other planets, and once remote controlled spy satellites became a better option than manned reconnaissance platforms, the funding simply wasn’t there.
NASA proposed several post-Apollo programs, all of which got shot down. An eventual Mars mission? Not for what it would cost. A permanent lunar base? Not for what it would cost. Extended-duration missions to the moon? Not for what it would cost. A permanently manned space station? Which would do what? Not for what it would cost. Finally NASA decided on the one thing it appeared that people were good for in space: piloting a reusable space shuttle, which could conceivably reduce launch costs for future projects. And even that was problematic. The Shuttle was technically risky and NASA couldn’t get the funding to do it right- it had to settle for a compromise design which limited risk and costs, and it still wouldn’t have happened except that the Air Force anticipated eventually conducting its own Shuttle launches.
The rest is history. The Shuttle couldn’t meet its performance goals and couldn’t reduce the risk of catastrophic loss enough to justify risking a crew and a billion-dollar investment.
This is a somewhat oversimplified view which fails to take into account significant differences between the operation of the Saturn IB and the Titan IIIC/M. It is true that the Air Force wanted a launch system with which they had prior experience with, and the Titan system, having been previously developed as an ICBM (LGM-25 ‘Titan I’ and LGM-25C ‘Titan II’) was such a system. As the space launch version (Titan 23B) was already being developed for use in launching the Keyhole seris of surveillance satellites, uprating it with the addition of the Titan Solid Rocket Boosters for use with the X-20 and Manned Orbiting Laboratory (MOL) was comparitavely simple given the previous research and development that the Air Force had done with solid propellant rocket motors on both the Minuteman system and the 260" diameter test motors which later led directly to the Shuttle RSRMs.
The operational advantages to the Air Force of using an evolution of the Titan system as opposed to adopting the Saturn are listed below:
[ul]
[li]The Air Force had existing service history and experience with the Titan system, including processes and procedures for fueling and defueling; the Saturn system was constantly evolving throughout its short production lifecycle[/li][li]The Air force maintained technical orders and crew training for the various Titan vehicles, and so would not be dependant upon a unique launch intergration crew as it would be fore the Saturn system, for which the only pool of trained crew were from NASA[/li][li]The Titan system and Gemini capsule, using analog avionics, was significantly less complex to integrate and operate than the more sophisticated Saturn family[/li][li]Titan enjoyed a nearly continuous high rate (for space launch rocket) production line which extended through the late 'Seventies (only cancelled due to a mandate from on high to use the STS exclusively for launches); Saturn was produced at lower production rates and somewhat intermittantly[/li][li]The only developed facility suitable for launching the Saturn IB was at Cape Canaveral, useful only for launching prograde trajectories; the Air Force desired a facility from which they could launch high inclination or polar orbit trajectories, hence the selection of Vandenberg AFB (Space Launch Complexes 4 and 6)[/li][li]The Titan IIIC/M, using storable liquid propellants (N[SUB]2[/SUB]0[SUB]4[/SUB] and UDMH) and solid propellant boosters, could be maintained on a launch pad indefinitely and be readied for launch in a few tens of minutes; the Saturn IB, with its LOX and (for the S-IVB stage) LH[SUB]2[/SUB] propellants, had to be fueled just prior to launch, limiting launch availability[/li][li]Finally, the Air Force new that the Titan booster would be in or available for production indefinitely and without competition or need for support by the civilian space program; it was clear even by 1966 that the post-Lunar future of the space program would be highly dependant upon political whims. [/li][/ul]
It is not that problematic to have a payload diameter exceeding that of the launch vehicle, and indeed both the Atlas V and Delta II/III, as well as the Falcon 9v1.1 and Falcon Heavy are or have been offered with oversized fairings to accommodate wider diameter payloads. This obviously has aerodynamic effects that have to be considered, but as long as the “hammerhead turbulence” effect (of going from a large diamter to a smaller diameter and then back to a large diameter within a certain length) is accounted for it is not a design constraint.
As it turns out, the issues that drove the Air Force to adopt the Titan III vehicle for their manned space programs (before they were cancelled entirely) were also applicable to the Air Force ‘Blue Shuttle’ program, in which the Air Force was obliged to adopt the STS as their exclusive heavy lift and crewed vehicle at enormous cost (over US$4B alone was spent upgrading SLC-6 at VAFB, and well over $1B sunk into development of the fiber-wound composite SRBs necessary to boost into polar oribt), with significant delays and schedule conflicts, and terminated ultimately because of the lack of system reliability and availability. After the catastrophic loss of Challenger and the resulting delays and reliability concerns, the Air Force leadership, which never warmed to use of STS to begin with, summarily cancelled Blue Shuttle and reopened Titan and Long Tank Thor (Delta) production as well as modifying surplus Titan II ICBMs into launchers. These vehicles, and the evolution therefrom (Delta II, Titan IV, and later the Atlas II) continued to serve the Air Force through the 2000s when they were supplanted and replaced by the EELV vehicles (Delta IV and Atlas V), as well as being used as the basis for JAXA’s first liquid propellant space launch vehicle, the Delta-based N-I, N-II, and H-I.
This capability turned out to be not nearly as useful or impressive as it was originally presumed to be. The recovery of satellites for return to Earth and refurbishment was done only once. Other servicing missions could likely have been done without the specific capabilities of the orbiter, and at any rate is often cheaper (if schedule prohibitive) to construct and launch a new satellite rather than to perform major refurbishment on existing satellites, especially in the case of telecommunications or nagivation sats which are already obsolecent by the time they are launched and are also in orbits too high to be accessed by the Shuttle without a supplementary space tug that was planned but never constructed. The main function for the Shuttle turned out to be delivering and helping to assemble modules of the ISS, which of course primarily exists as a political sop and a place to fly the Shuttle to.
To be precise, the STS met the performance goals as defined in the latest proposal specifications (although not as desired in the original concept), and the empirically realized reliability (of roughly 98%) was exactly where the technical management estimated (between 1:50 and 1:100 incidence of catastrophic loss of vehicle). Where the STS failed was meeting cost and schedule expectations, notwithstanding the setbacks presented by the multi-year hiatus after the loss of Challenger and Columbia and dependance upon the STS as a primary or exclusive heavy lift vehicle.
The lessons learned of the STS program are thus:
[ul]
[li]Reusability does not equate to cost savings, schedule reduction, or improved reliability[/li][li]Spaceplane configurations present significantly greater complexity and risk with only marginal improvements in operational capability or flexibility compared to expendable launch vehicles and blunt-body capsules[/li][li]At the current state of the art you have to assume a non-negligible likelihood for catastrophic loss of vehicle at any point in ascent, and make provisions for protection and recovery of crew accordingly[/li][li]A ‘safety culture’ for crewed launch vehicles must include realistic and independent assessment of risks rather than just to be oblivious to known issues or accept out-of-design degradation on the rationale that if it hasn’t failed yet it won’t cause a problem in the future[/li][li]It is necessary to both evolve a system as you learn more about it in order to drive out design risks, and make provisions for integrating such lessons into a next generation design[/li][li]For a vehicle such as a shuttle, it needs to be recognized that it exists as one part of an overall space architecture; without funding and approval for developing other parts of that infrastructure, you are left with a vehicle that has no place else to go and a vary narrow range of missions it can support[/li][/ul]
The culture and philosophies that lead to the essential failure of the STS to significantly advance the technology of crewed spaceflight live on and are even exacerbated in the now-cancelled Constellation and the Space Launch System. The low launch rate, lack of clear long term planning and supporting infrastructure, and compromises in engineering rigor which ultimately plagued the STS are also being built right into the SLS. A progression from the maturing of the Saturn family to evolving a next generation of separate heavy lift and partially or completely reusable small lift crewed space launch vehicles, plus a space infrastructure would likely have us maintaining a significantly expanded and possibly sustainable indefinite human presence in orbital space, with the potential for crewed interplanetary missions (although the value of a crewed landing mission with its wide array of protections and support versus robotic probes and rovers remains questionable from a purely technical standpoint). Certainly we gained little of value out of the entirity of the three decades of the STS program that could not have been accomplished more cheaply by other means. Whether anyone in the decision chain has learned and can implement these lessons remains to be seen.
It seems to me that re-entry is a major problem for all spacecraft. In the mid-1960’s there was a study about a different way to do this-via a balloon-parachute concept (“ballute”).
As I recall, astronauts would 'bail out of the spacecraft, and descend gradually via a large balloon-when the atmosphere got dense enough, they would ditch the balloon and open a large parachute.
what happened to this idea?
The points about the USAF preferring to build on its operational experience with an upgraded ICBM are taken, but that still leaves the following:[ul]
[li]Payload capacity. The Titan III took upgrading of the original booster to its limit; the Saturn IB was a heavier booster to begin with, and could be upgraded further.[/li][li]Payload dimensions. Yes, the booster main tank diameter isn’t an absolute limit, but a wider tankage would have made things easier and offered more options.[/li][li]Storable propellent seems a minor consideration. Weren’t all Titan III launches planned well in advance? The idea that the Titan III could be kept on indefinite standby like a silo missile seems unrealistic.[/li][li]The Titan was mass produced precisely because it was the USAF/DoD’s heavy launcher; if the Saturn had been adopted by the USAF, it would have been continually produced, whether NASA used it or not.[/li][li]In a similar vein, launch faciilites would have been built at Vandenberg if the Saturn had been adopted.[/li][/ul]
IMO they should have developed parallel programs - the next-gen heavy lift vehicles to take sections up for the ISS (or it’s primitive clone) and for manned missions to the Moon, and the Shuttle for capture-and-repair work on satellites, special near-Earth low-g sciences, and to carry crews back and forth from the space station (you know, like a shuttle).
I know they couldn’t have both, because our politicians were (and are) too blinkered to understand how important it might have been, but a man can dream. As it is it stands now, I have no faith in man’s future in space, and feel we’re doomed to smother to death over the next 10 generations. Our only hope at this point is China, and as much as I dislike their government, they’re still human beings, and as such I’m rooting for them.
Another error in the administrator’s logic is that a billion dollar savings results in an extra billion the next year. The reality is that they would have been hit with a billion dollar budget cut because, “Hey, you didn’t need it and we can put that money towards another stealth bomber.”
Thats what I was thinking totally. When people have a grand in their budget, and they don’t spend but 900, then their budget is lowered the next year. There is no incentive to really in the end save money because a dollar not spent is a dollar you can’t spend next year.
I love the lore and the feeling that NASA gives me deep in my chest, but I think at best it will always be a slow to evolve expensive money pit, because it doesn’t have a guaranteed budget. If it ALWAYS got, say, 100 billion a year (random number picked from the air), then I bet the very large and powerful minds at NASA would be a lot better at getting costs down, because they could actually save and plan for years that they would need to spend more.
For example, they could save money and only launch 2 probes in 2015 and 2016 so that they could roll the money they saved in those years for the big huge mission to the moon or mars in 2017. As it is now, they would just lose the money.
Although I would be very willing to give them a large fixed budget every year, not many people get excited like I do about space, and really, we do have starving people here at home that could use the money. Its tough when there is only so much to go around.
Maybe NASA could do something like NASCAR where you could see the “Bud Light Shuttle” flying out of the “Nextel Space Port” or something. But probably not.