© 1995 by Donald F. Robertson.
E-MAIL: DonaldFR@DonaldFRobertson.com.
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This article originally appeared in very different form in Astronomy Magazine.
by
Donald F. Robertson
NASA is on the verge of a great experiment. It is an experiment in the grand American tradition of exploration. With this experiment, a man whom many describe as the best NASA Administrator since the Apollo years hopes to open the new frontier once and for all -- to exploration, industry, and eventual settlement and trade.
The Space Shuttles, while in excellent condition, are growing old. In theory, they are capable of flying for the foreseeable future. But keeping the orbiters in the air costs a lot of money. Post-Challenger operations have proven extraordinarily reliable, but it is only a matter of time until another accident grounds the fleet -- this time possibly forever.
As experimental rockets, the Space Shuttles broke technological frontiers, becoming the first regularly re-usable launch vehicles. As operational "spaceliners," they have made human spaceflight into a relatively routine activity. Almost every flight demonstrates a new capability in space. Yet, the Shuttles have done little to reduce the high cost of reaching orbit or to duplicate the frequent, every-day occurrence of an airliner leaving the airport tarmac. While the orbiters can and will be improved (as we'll discuss later on), they will never become the fleet for a true "spaceline."
So why not simply build a new and better Space Shuttle? The problem, of course, is money.
Today, flying the Shuttle costs NASA something between $3 billion, and $5 billion or more, every year, depending on what you bill to the program. Soon, another $2 billion, or more, will be spent each year building and supplying the Space Station. These costs are very hard to reduce without drastic revisions in the way NASA does business. With great effort, NASA has managed to cut the Shuttle's budget by about one-fourth. There is little left to cut: two senior Shuttle managers recently resigned, apparently (although they both deny this) to protest the safety risks inherent in further cuts planned by NASA.
It gets worse. The Clinton Administration, desperate to keep the deficit under control, reportedly has told NASA to expect substantially smaller budgets -- around $12.6 billion -- by the end of the decade. Factor in inflation, and this is a huge cut; the space agency gets a little over $14 billion today. Although both political parties generally support greater space spending, Republicans in Congress, committed to a balanced budget, will find it hard to oppose cuts proposed by the supposedly spend-thrift Democrats.
Even without those cuts, there was little money to develop a new, second-generation shuttle that might be cheaper to run. Yet, says NASA's request for industry's help, a cheaper way of getting into orbit is essential if the United States is "to promote the creation and delivery of new space services." These services are required for "the continuing economic development of near-Earth space, and [to] open the space frontier to human exploration." Needless to add, there also is no money to build lunar or Mars bases, to send prospecting missions to the asteroids, or for any other dramatic new initiatives.
What about all that money tied up in flying the Shuttle? say NASA's critics. Even part of that money could represent a solid down-payment on the $5 billion to $10 billion a new shuttle is estimated to cost, again depending on whom you listen to. Why continue flying the Shuttle if that money can better be used to develop a better vehicle?
Politically, gutting the Shuttle completely is extremely risky. Unless you think some aerospace company is ready to take over the existing space program, it means abandoning human spaceflight for the years it will take to ready the new vehicle. That, in turn, means abandoning the Space Station, viewed as necessary if there are ever to be human missions into the Solar System. All forward momentum in human spaceflight, both technical and political, would be lost. A new, replacement shuttle might not actually get built. Conceivably, quitting now could mean that a broke United States abandons the new frontier forever.
NASA has been grappling with these contradictory pressures ever since the Shuttle started flying and it became clear that it could not live up to the agency's hopes. None of the alternatives are acceptable to the space agency, nor, apparently, to the nation. The result has been two decades of indecision.
In an era of relentlessly contracting budgets, the space agency's hyper-kinetic administrator, Daniel Goldin, appears to believe that a dramatic reduction in the cost of getting into space is NASA's only hope for maintaining a dynamic space program. House Republican leader Newt Gingrich appears to agree: he has been quoted as saying that NASA's overriding mission should be cutting the cost of getting into orbit. This fits with the on-going mantra of Goldin's administration at NASA: "faster, smaller, cheaper, better." It is also just the kind of cut-the- money-without-reducing-your-(expensive)-goals thinking that led to the Space Shuttle and all of its problems.
Goldin, however, may really be different. He has relentlessly forced other parts of the space agency to tighten their belts. He cut billions from the long-term cost of the Space Station by simplifying the program and bringing in the Russians; by reducing the time has to fly from thirty to fifteen years; and by insisting that the prime contractor, Boeing, cut their costs. He signed an innovative contract with Boeing so that the company earns twenty-five cents of every dollar it saves on the Space Station while part of any new cost over-runs will be billed to the company. He cut $1 billion a year from the cost of operating the Space Shuttle. He told planetary scientists to keep the cost of every new mission below $150 million, and to launch them on a $50 million Delta rocket, or even cheaper vehicles. Then, when every proposal came in at exactly $150 million, an angry Goldin told engineers that missions which cost well under the budget ceiling will have a higher chance of being chosen for flight. Goldin's message is, Cut costs, or I'll cut them for you.
Launch vehicles are next. Goldin has stated outright that NASA will not develop a replacement for the Space Shuttle. The agency cannot afford it.
Traditionally, when NASA does not have enough money, they look to the military for help, particularly the Air Force. Today's Air Force is half the size it was in the mid-1980s, and they are in no mood to help out NASA. Anyway, the Clinton Administration has decided that the Air Force will remain responsible for maintaining and improving the United State's staple of expendable rockets, while NASA develops new-generation launch vehicles -- with little or no new money.
So what's a NASA administrator to do?
For years, some advocates of commercial space have claimed that, if only the government would get out of their way, private industry would explode into the Solar System. Daniel Goldin is about to give the aerospace industry the chance to live up to their rhetoric.
A century ago, the United States' government promised title to vast swaths of land to any entrepreneurs who would build rail roads to tie the country together. Later, the Navy worked with those same commercial rail roads to develop the diesel-electric engine, which drove early military submarines and powers most of the locomotives in use today. Likewise, the government used contracts to deliver mail to help the early commercial airlines. The Defense Advanced Research Projects Agency guaranteed the launch of small payloads, which let Orbital Sciences Corporation raise enough money on Wall Street to start developing their revolutionary Pegasus Air-Launched rocket. [The author is a small shareholder in Orbital Sciences Corporation.] That set the financial foundation for the new, small launch vehicle industry. Contrary to modern economic mythology, very few transportation- related industries ever got started without government help.
Many space advocates have pushed a similar model for space. The government, loathe to lose control of a technology with dire military applications, has resisted wide-spread commercialization of rocketry. Now, lack of money -- and Europe's success at commercializing Ariane and taking off with sixty percent of the launch market -- is forcing the Clinton Administration and NASA to re-consider the idea.
NASA's plan is to pay for a lot of research. Some of this research would be on the ground. More would fly on a small reusable rocket called the DC-X or Delta Clipper, which NASA has inherited from the "Star Wars" Ballistic Missile Defense Office. Delta Clipper was built to test some of the technologies for a vertically-landing Single-Stage-To-Orbit (SSTO) launcher. That re-usable rocket was damaged in its last flight test, but NASA is refurbishing it to test new technologies for the future Shuttle. [The re-named Clipper Graham was, of course, destroyed in a landing accident in 1996.]
The space agency also will start two new and relatively small programs. One is to develop a tiny, fully or nearly re- usable rocket designed to lift one- to two-thousand pounds to low Earth orbit at "significantly reduced" cost. This will accomplish two essential objectives: it will prove beyond question that an SSTO is possible; and it will provide a vehicle to test new technologies at higher speeds than the Delta Clipper can achieve. It may also provide an operational vehicle to lower the cost of orbiting small payloads. Test flights should begin in late 1997, and first orbital flight in mid-1998. This new vehicle is called the X-34.
The second program is a follow-on to the Delta Clipper project, called the X-33. In many ways, rocket speed equates to money; less speed costs less money. It takes much less velocity to lob yourself into a sub-orbital trajectory than it does to attain orbit, even if both are at the same altitude. A series of sub-orbital missions that re-enter the atmosphere should be enough to test most of what any new rocket needs to do to fly all the way into orbit, at much less cost and risk than developing a new orbital vehicle from scratch.
The X-33 will be a sub-scale model of a fully re-usable Single-Stage-To-Orbit shuttle that NASA will use to solve the problems needed to build the real thing. As NASA puts it in their revised agreement to industry: "The X-33 will demonstrate the critical technologies needed for orbital SSTO rockets in realistic operational environments. To the extent practical, the X-33 will be tested in the ascent and re-entry flight environments of a full-scale SSTO rocket," while also demonstrating the flight techniques and low-weight materials needed for a real SSTO.
Goldin has promised to find a few hundred million dollars in NASA's budget for these two projects. That will pay for approximately half of the $140 million X-34. NASA's share of the X-33 program is estimated as $18 million for initial studies, and $650 million to build the test vehicle. Aerospace companies, if they want to develop a second generation Shuttle with NASA's help, must match these amounts, "as a minimum," says NASA.
And that is where NASA stops. If there is to be a new operational Shuttle, it has to be a commercial vehicle. There will be no more free lunch to the aerospace industry. If American companies want to compete in the market to deliver satellites and material to orbit -- now dominated by the Europeans, and increasingly by the Russians and Chinese -- then the aerospace companies themselves will have to cough up most of the money. In a symbolic move, NASA's document to industry asking for cost estimates to do the work, normally called a "Request For Proposals" or RFP, is this time called a "Cooperative Agreement Notice" or CAN.
Is this indeed the new NASA? Well, maybe. Already there are signs that NASA may insist on designing this "commercial" vehicle, possibly in return for providing money. In fact, in its revised agreement, the agency responded to corporate criticism over the level of required government involvement, saying, "By definition (policy), cooperative agreements require substantial government involvement (not cash only). . . ."
NASA's requirement to deliver payloads to the Space Station is very different from industry's need to reduce the cost of access to those orbits frequented by communications and commercial Earth observation satellites -- and not, at least yet, by space stations. A vehicle that can service these "commercial orbits" can probably service the Space Station, but a Space Station delivery tug cannot necessarily reach geostationary or polar orbit at reasonable cost. Design a spacecraft to service commercial missions first and government missions second, say NASA's critics.
At first, NASA specified a minimum payload of 25,000 pounds and other specific requirements for the X-33. These included things like seven days between flights, seven days orbit endurance, and a fifteen-by-thirty foot cargo bay. NASA backed down under heavy Congressional criticism, and, while not abandoning these "goals," the agency now states that the payload is "a preliminary assessment of [the] minimum single payload element weights that are required to support the Space Station," according to the agency's revised agreement. This requirement "is substantially lower than currently planned delivery capability to the Space Station by the Space Shuttle."
In other words, a small vehicle that flies small payloads frequently would be acceptable instead of a large vehicle that can carry whole Space Station logistics modules. This is crucial for a commercially-oriented spacecraft. It is much cheaper and easier to develop a relatively small vehicle than a large one.
Critics also argued that, after the Shuttle experience, NASA should not dictate that the next-generation shuttle project aim for the most difficult goal, a Single-Stage-To-Orbit vehicle that can go all the way to orbit as a unit, without stages. NASA's response: "While the next-generation re-usable launch vehicle decision by the end of the decade may not result in an SSTO, the focus of the on-going Re-usable Launch Vehicle technology program is SSTO." That is because "past studies indicate [that an SSTO represents] the best potential for achieving the lowest-cost access to space while acting as a Re-usable Launch Vehicle technology driver (since [an SSTO] also encompasses the technology requirements of re-usable rocket vehicles in general)." In non-government language, if you aim for an SSTO you also develop the technology needed to achieve a lesser goal.
And now the crucial question: will industry really come to the table with their purses? Five billion dollars is a lot of money even for a giant aerospace company. Companies are being asked to bet on a high-risk project without a large, definite market. But, say critics of the way things are now, if the government is not paying the bills, maybe it won't cost quite five or ten billion dollars to develop the new vehicle. Maybe the aerospace industry will search their collective souls and find a way to do things a bit faster, smaller, cheaper, and better.
As always, when dealing with money, the devil is in the details.
The smaller X-34 is a relatively straight-forward project. NASA puts up $70 million; the winning company matches it. $140 million, four years, and a lot of luck later, the United States has a modern, re-usable small launch vehicle, a rocket for which there is an un-questioned market.
Unsurprisingly, the bigger X-33 is a bit more complex. For a start, it is a test vehicle. Even though industry is being asked to put up $650 million dollars in matching funds, it will be hard to make money on it without a huge new investment in an operational vehicle. The operational rocket will certainly cost a whole lot more than $650 million and NASA will not pay for anywhere near half of it.
The current plan is for NASA to fund the first $18 million this year, split among a number of companies, for the initial studies. Uniquely, these studies must include proposals for financing half the test vehicle, and for commercially funding the operational shuttle. NASA has made clear that realistic non- government funding schemes will play a large part in deciding which company gets the contract. Even more uniquely, foreign companies are expressly encouraged to participate.
This Phase-I is to be completed in fifteen months. At that point, in 1996, the White House and Congress are to use these studies to decide whether to go ahead with the full test vehicle. Assuming a positive decision -- a big assumption, given that the budget deficit is unlikely to be significantly smaller -- the Phase-II test vehicle must complete its tests before the end of the decade, according to NASA's revised agreement to industry. These goals "are focused toward demonstrating the technology to build reusable launch vehicles with aircraft-like operations," according to NASA. This is Phase-III. "If fully successful, [the goals] will result in a low-risk, low-cost development of a commercially-operated Re-usable Launch Vehicle system." Conceivably, while the fully re-usable third-generation shuttle is being developed, the X-33 test vehicle might be upgraded into the re-usable first stage of a two-stage interim orbital vehicle. Maybe industry can make money early in the project after all.
And don't forget the humble DC-X. Bill Gaubatz, corporate manager for the original DC-X and now X-33 Program Manager for McDonnell Douglas and Boeing, told Astronomy that McDonnell Douglas is re-furbishing that vehicle to conduct that last of the originally planned series of flight tests in April 1995. Then, new components will be retrofitted to test SSTO technologies in a low-altitude flight environment. The re-designed vehicle is called the DC-XA, for "Advanced." The upgrades include new composite structural components, composite fuel tanks and fuel lines and valves, experimental electronics, and modifications to improve the RL-10 engines' efficiency.
All of this is certainly faster, smaller, cheaper, and better. Critics -- and there are a lot of them -- say the proof is in the pudding.
Advocates who fought for the project in Congress say that NASA's schedule is way to slow. Calling themselves the Space Access Society, this group, which includes several Congressional staffers, distributes an electronic newsletter over the Internet. In the most recent issue, Executive Director Henry Vanderbilt wrote that the three-phase project creates delay that is "both unnecessary and potentially fatal. We have some momentum from the DC-X program now; we must not allow it to dissipate." Choosing a hardware contractor "by the end of next summer, followed by a two-year construction phase, ought to allow flight by late 1997," rather than NASA's 1999, says Vanderbilt. "The flight vehicle(s) might not be as fancy or capable, but they will fly. Delay only encourages [the] paper-aircraft-forever syndrome."
SSTO advocates in Congress have fought long and hard to keep the project out of NASA and in the "Star Wars" office. The Ballistic Missile Defense Office successfully developed and flew the DC-X from a standing start in less than three years for the astonishingly cheap price -- for rocket work -- of $60 million.
They lost that fight, but NASA has promised that this time things really will be different. No more vast government Shuttles or Space Stations, carefully designed to employ every NASA office. NASA will run the new program in the model of Lockheed's "Skunk Works" advanced development office. The Skunk Works has a reputation for developing unique vehicles -- the F- 117 stealth fighter; the old SR-71 spy plane that is still the world's fastest publicly known aircraft -- in a few years, at relatively low cost, with a tiny team of engineers under one manager.
It remains to be seen if NASA is capable of copying this model. NASA has vast institutional interests: every one of NASA's centers (and its associated member of Congress) will want a piece of the action and it will take extraordinarily tough management to tell them, No. Promisingly, NASA fought the Air Force to get the officer responsible for the DC-X program -- former Shuttle astronaut Lt. Col. Gary Payton -- to run the X-33, and got him.
Asked if the post-Cold War aerospace corporations really could or would pay for a commercial shuttle, Bill Gaubatz said yes. "We are in this for the long pull. Corporate money, Wall Street money, investment money -- whatever you want to call it -- is out there, if you can demonstrate that you have a technology and a market. This has to be driven by economics. The government needs to do the risk reduction and NASA has to be a predictable customer." Can NASA be a predictable customer? "It's predictable today," says Gaubatz. "The government spends seven billion dollars per year on space transportation."
Advocates are trying to get Congress to change the laws so that NASA can promise a long-term guarantee to buy launch services from a single winning company. This is the same model the Advanced Research Projects Agency used to help develop the Pegasus. NASA would say to the aerospace industry, in effect, We will guarantee to launch so many kilograms of payload into orbit if you will develop a cheaper rocket.
This is another goal space advocates have been pushing for years. It should be relatively easy to do. The Space Station will require a lot of material to be delivered to orbit, day in and day out. Gaubatz agreed that the Space Station could prove to be the principle market that allows private companies to raise enough money to develop a commercial re-usable launch vehicle. In addition, there is increasing evidence that a large, truly commercial launch market might really exist.
Today's communications satellite industry cannot keep up with demand. If launch costs were reduced, this market might grow even faster, and new markets might appear. Then, commercial space could snow-ball: lower launch costs would create new markets which would encourage companies to invest more money in lowering launch costs still further. Even if that future proves too rosy, lowering launch costs would enable the United States to take a greater share of whatever launch market is out there. Today, the country that used to launch all communications satellites now launches less than forty percent, and falling.
What will the X-33 be like? It is early to say, the program is just getting started. However, some characteristics of the new shuttle are not open to negotiation. They are dictated by physics and the fast development schedule.
The large X-33 will almost certainly use a variant of a current rocket engine, according to speculation in the aerospace trade press. NASA's Goldin is in too big a hurry to wait a decade for a new engine to be developed. The Space Shuttle Main Engines have all the performance that is required, are well understood by NASA, and are re-usable -- albeit with major refurbishment between flights. New turbopumps and other up- grades are making these engines more truly re-usable -- the goal is ten flights without major work -- and much safer. Getting a better engine would cost several billion dollars, take many years, and not necessarily be all that much better.
One alternative being considered is something called a "tri- propellant engine" developed by the Russians. This burns dense kerosene fuel when the rocket is moving slowly, deep in the atmosphere, then switches to lighter hydrogen at high speeds above most of Earth's air.
Kerosene is heavier than Hydrogen. You can carry a greater mass of kerosene in a given tank. It burns at a relatively low temperature so its exhaust leaves the rocket nozzle at a slower speed, but its greater weight means that it provides more reaction to the rocket. This is important early in a rocket's flight, when the vehicle is still heavy with un-burnt fuel.
Hydrogen is lighter and takes larger and therefore heavier tanks, but it burns much hotter; it leaves the rocket at very high speed. It provides much greater efficiency, but less push. It is must useful high above most of the atmosphere, when much of the fuel has been burnt and the vehicle is relatively light.
The design differences between a kerosene-burning engine and a hydrogen-burning engine are not all that great. In theory, one engine could burn kerosene close to the ground, then switch to hydrogen, burning each fuel with the same supply of liquid oxygen oxidizer -- hence the name "tri-propellant."
The idea has many advantages. You are burning the type of fuel that is best for each altitude while needing just one kind of engine, saving the weight of separate engines for low- and high-altitude flight. (The Space Shuttle, for instance, gets most of its thrust close to the ground from the Solid Rocket Motors with their heavy fuel, then the hydrogen-burning main engines provide all of the thrust once the SRBs are dropped.) Since you are not burning high-volume hydrogen the whole way to orbit, you can get by with smaller fuel tanks, which makes for a smaller, lighter, and simpler vehicle. A smaller, less weighty vehicle skips lightly into the atmosphere and can use a simpler and lighter thermal protection shield on the way home. And, in desperate need of hard currency, the Russians are eager to sell. The rub is that the Russians have not actually used this rocket -- and "paper rockets" can be found at home.
The chances are high that NASA will stick with improved Shuttle-type engines and / or an up-rated version of the RL-10. The RL-10 was world's first high-energy rocket engine and is still used on the Centaur upper stage. This is not just because these rockets were designed and made in America. SSTO advocates in Congress believe that tri-propellant engines are needlessly complex, and that sticking to one fuel is more than worth the larger vehicle required. After all, the principle reason for the Shuttle's high cost is not its (cheap) fuel, or its inefficiency, but its extreme complexity. The Shuttle needs a "standing army" of engineers to tinker it into operation. Hence the cry of SSTO proponents: above all, keep it simple.
Given that the United States' budget problems will continue far into the future, the alternative to a commercial shuttle appears to be . . . nothing. A grim future of continuing to launch a few commercial communications satellites and the odd planetary probe on ancient, un-reliable, and hugely expensive converted Inter-Continental Ballistic Missiles. No true exploration with astronauts, no industries in space, no human settlement of the planets.
Maybe. But there is, in fact, a middle road. The Space Shuttle, by some measures, is a hugely capable spacecraft. The operative word is "spacecraft." The Shuttle's many problems mostly involve the process of getting into and, to a lesser extent, out of orbit. While in space, its pilots view the orbiters as "exquisite" flying machines, extremely stable platforms capable of the most precise maneuvers. In orbit, astronauts truly "fly" the orbiters, unlike any spacecraft ever before. By keeping the orbiters in space longer, you can get more benefit out of each launch. Likewise, replacing the orbiter with payload, the Shuttle launch system can lift the same mass as an Apollo Saturn-V for about one-third of the cost.
The Shuttle's costs are "fixed." That is, the major expense is not actually flying the Shuttle. It is the cost maintaining the infrastructure of launch pads, control rooms, and that standing army of engineers to refurbish the orbiters. "Fixed" costs are extremely hard to cut, and NASA deserves credit for successfully cutting these costs by about one-fourth.
On the other hand, refurbishment hardware and fuel costs are relatively low. If you fly the Shuttle more often, the additional "incremental" cost on top of the "fixed" cost is high, but nowhere near the almost-a-billion-dollars-per-flight estimates of those who divide the total annual cost of operating the Shuttle system by the number of flights each year. (Recall that this is anywhere from $3 billion to $5 billion divided by five to eight flights, depending on who is doing the counting.) The incremental cost of one Shuttle flight is hard to pin down, but probably is somewhere in the neighborhood of three hundred million dollars, or even less. This is not all that much higher than flying same payload on old expendable rockets.
So, one alternative is to continue flying the Shuttles, but do it more often and have each mission stay in space longer. This is politically unpalatable. Sticking with the current Shuttle maintains a very high cost item indefinitely on the Federal books. Simultaneously, since it eats up all the money, keeping the Shuttles flying limits what we can do in space to what the Shuttle can do. It does not allow any grand new projects for politicians and NASA engineers to sign their names to.
It is, however, a realistic option. Investing more money in the Shuttle system could enable a proven rocket to fly substantially more often without a huge up-front investment or vastly higher costs. The Shuttles have achieved over [eighty, as of early 1997] successful flights with only one failure; the Shuttle is the second most reliable large rocket ever developed, conceding second place only to the much smaller Delta. It orbits a huge payload, and with modification can carry a much larger one. The crew have proven their worth time and again, most recently with the repair of the Hubble Space Telescope.
To some degree, this strategy is already what the United States has chosen, by default. Unable to make a decision and with no alternative in sight, the country simply continues to fly and slowly -- inadequately -- improve the Shuttles. In addition to the new and safer main engine turbopumps, the agency is increasing the nozzle throat diameter to let the engines run at lower pressure and less stress. New, super-light weight external tanks are being developed. Another project is changing the interior control panels from old electromechanical equipment that needs a lot of maintenance, to a "glass cockpit" that is less prone to breakdown and provides a lot more "control" for less weight and money. Other projects to re-redesign the Solid Rocket Boosters and switch to lighter fiber optic wiring have been canceled or put on indefinite hold.
Sure, the Shuttle costs a lot of money, but we're getting a lot for our money, too. People forget what things were like before the Shuttle. Human orbital missions occurred two or three times a year, accomplished almost nothing beyond the flight itself, and by any measure the total cost was far higher.
Are the orbiters up to the job? Apparently so. Over the past few years, NASA has refurbished and upgraded the Shuttles. In the process, they underwent detained structural examinations. NASA representatives claim that the orbiters are in great shape and probably can fly as far into the future as necessary.
Is there a way to take the Shuttles out of the government budget while keeping them flying, so that NASA can concentrate on helping industry develop a replacement? Maybe so.
There is revived talk both in NASA management and in Congress of commercializing the Shuttle system. This would consist of setting up a government chartered corporation, like Amtrak or the European's Arianespace, which launches Ariane rockets. In a government chartered company, the government puts up the money, but the organization otherwise behaves much like a private company. The idea has a long and successful career in the history of exploration -- the British East India Company that did much to create Britain's commercial empire was a government chartered company.
The idea also has one key advantage that many of the other dreams of space advocates don't: it is known to work. It allows semi-private projects that are too expensive or un-economic for the private sector to undertake by themselves.
Rockwell once offered to take over Shuttle operations, as did several other companies. Probably much to the their subsequent relief -- this was before Challenger -- NASA declined. NASA believed Rockwell could not successfully make a commercial operation out of the Shuttle; cynics believe NASA simply did not want to lose control of the program. Today, however, the Shuttle is a successful, regular operation, and if the government were willing to pay what launches actually cost, it could probably be commercialized.
A commercial Space Shuttle would remove that big item from NASA's budget. NASA would pay for each launch when and if needed, and other customers might be found to pay part of the total bill. Republicans in Congress, who like the idea of commercializing government services, might support the idea. It would free up NASA money to do what NASA was originally founded to do: develop new technology.
Say, the new technology for that Single-Stage-To-Orbit shuttle . . . and then, the odd lunar or planetary base?