Space Architecture

Sunday, February 11, 2007

Launch Costs

Found this article on the The Space Review, dated 27 September 2004.
A central tenet of the faith held by advocates, entrepreneurs, and others in an expanded presence in space is that launch costs must, and can, come down. These people will often debate endlessly the means for lowering these costs—reusable launch vehicles, big dumb boosters, or exotic technologies like a space elevator—and even what the magic price point is: $1,000, $500, or $100 a pound, and sometimes lower. However, all will agree that launch costs today are far too high to permit the commercialization and exploration of space they all desire.
During a presentation at the annual AIAA/Utah State University Conference on Small Satellites last month in Logan, Utah, Steven Buckley, an Northrop Grumman aerospace engineer who works with the Rocket Systems Launch Program (RSLP) at Kirtland Air Force Base in New Mexico, noted a trend in launch vehicle costs and capabilities. The RSLP has been involved with a number of small military launch vehicles in the last decade, including efforts to reuse decommissioned ICBMs as launch vehicles. Buckley noted that while the capabilities of the vehicles have grown—the Minotaur 4, derived from the Peacekeeper ICBM, has nearly four times the payload capability of a Pegasus XL—the vehicles have all had “flyaway” costs of about $20 million a launch. “It’s difficult to get the total flyaway costs below about $20 million,” he concluded.
Buckley’s analysis found that, for a typical RSLP launch, the launch vehicle contractor costs take up about 65 percent of the total flyaway cost: $13 million for a $20 million launch. Launch agency costs take up 15 percent, with range costs taking up another 10. The remaining 10 percent is split evenly between the launch site facilities and miscellaneous categories. Many of those costs are fixed, so that if the vehicle hardware cost goes down, the share of the flyaway costs absorbed by those other components increases: Buckley estimated that if the launch vehicle contractor costs were cut roughly in half, to $7 million, the total flyaway cost would still be about $13 million.
So, your rocket, whether it's carrying satellites or people is going to cost at least $20,000,000? That sounds similar to the idea that a decent used car in Houston, TX, is going to cost at least $3,000 to $6,000, because the car is going to have some cost of metal, plastic, engineering, safety equipment, and air conditioning.

What's new(er) since 2004? TSR has this article about the Aquarius launch system.

While the failure of a launcher carrying only consumables might be regrettable, it’s not because of the payload value. If many tons of commodities were to be delivered annually and launched in one-ton shots, the loss of one shot would be written off and a replacement launch performed in short order. A number of replacement launches would in fact be expected and included in operating plans. Furthermore, if the consumables were launched in advance of need and maintained on a depot until required, the orbital user would never experience a delay in deliveries or interruption of service even if a commodity-carrying launcher suffered a failure!

For this system to work, the consumables-only launch must be a lot cheaper than the launch of a high-value, possibly irreplaceable payload. Previously published studies show that allowing launch reliability to be reduced significantly, to between 0.67 and 0.8, can provide a way to cut launch cost by an order of magnitude. While a 0.67 delivery success rate might seem shockingly low from a traditional aerospace perspective, it is accepted routinely in terrestrial low-cost delivery systems. Aqueducts and high-tension power lines, for example, routinely lose one-third of their payloads en route, yet are highly successful.

As discussed here previously, the Aquarius system under development by Space Systems/Loral (SS/L) is built on this premise. (See “The myth of heavy lift”, The Space Review, May 17, 2004) The Aquarius launcher concept is a simple, low-margin, pressure-fed, floating-launched vehicle. Its design strategy allows mission reliability reduction to the extent that net delivery cost to orbit is minimized commensurate with the low intrinsic value of its one-ton payloads. SS/L has been developing this concept since 1998 and has been funded by customers to pursue it, with the concept receiving increasingly serious attention as it advances.

The Wikipedia entry for Aquarius has this pdf as a source. Excerpt:

The Aquarius launch vehicle was
discussed in a previous article (Space
Times, May/June 2001), and requires a
total liftoff thrust of 400,000 pounds. Here
low cost launch is obtained by relaxing
reliability. Aquarius system reliability
might be only 67%, so engine reliability
might be 93%. Aquarius will ship low
cost consumables and low-cost, replaceable
spacecraft and other equipment to
orbit. Since stringent protection of reliability
is not required, the cost per pound
to orbit could be $500, an order of magnitude
below that of any present launcher.

Five-hundred dollars per pound! I hope that Space Systems/Loral is successful!


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