alternatehistory.com

Last year Lockheed has taken over the abandonned DIAGONAL small launch vehicle, a derivative of France national launcher Diamant. The only launcher on the small satellite market is the SCOUT. The G1 variant can place up to 200 kg in orbit. Most SCOUT launches relate to the TRANSIT navigation system.

The TRANSIT system is primarily used by the U.S. Navy to provide accurate location information to its Polaris ballistic missile submarines, and it was also used as a navigation system by the Navy's surface ships, as well as for hydrographic survey and geodetic surveying. Development of the TRANSIT system began in 1958. The first successful tests of the system were made in 1960, and the system entered Naval service in 1964.

The Chance Vought/LTV Scout rocket was selected as the dedicated launch vehicle for the program because it delivered a payload into orbit for the lowest cost per pound. However, the Scout decision imposed two design constraints.

First, the weights of the earlier satellites were about 300 lb each, but the Scout launch capacity to the Transit orbit was about 120 lb (it was later increased significantly). A satellite mass reduction had to be achieved despite a demand for more power than APL had previously designed into a satellite.

The second problem concerned the increased vibration that affected the payload during launching because the Scout used solid rocket motors. Thus, electronic equipment that was smaller than before and rugged enough to withstand the increased vibration of launch had to be produced. Meeting the new demands was more difficult than expected, but it was accomplished. The first prototype operational satellite (Transit 5A-1) was launched into a polar orbit by a Scout rocket on 18 December 1962. Since then the constellation has been replenished on a regular basis. SCOUT rockets are launched at a rate of two to three a year, and Lockheed really hopes to tap into this market.

Lockheed however realizes that the small satellite market isn't big enough and as such they intend to create more flight opportunities by flying DIAGONAL boosters to space station Liberty. “This might become a big market and boost our flight rate up to reuse of the L-17 first stage make sense.”

ECONOMICS OF ROCKET REUSE

Lockheed aerospace engineer Maxwell Hunter recently gave a lecture about reusability to a gathering of the AIAA - the American Institute of Aeronautics and Astronautics.

Reflight of a previously used rocket stage on a subsequent flight is dependent on the condition of the landed stage, and is a technique that would have been used on the cancelled Space Shuttle. Maxwell Hunter projects that the reflight step of the DIAGONAL program will be straightforward, because of the multiple full duration firings of the engines that have been done on the ground, and the multiple engine restarts that have already been demonstrated, with no significant degradation seen. DIAGONAL is a simple vehicle - the engines, some structure and the plumbing - but rocket engines, even pressure-fed, are high performance machines with little margin for error. Several industry analysts continue to see potential problems that could prevent economic reuse because costs to refurbish and relaunch the stage are not yet demonstrated. Moreover, the economic case for reuse will be highly dependent on launching frequently, and that is simply unknown. The inherent simplicity of DIAGONAL pressure-fed Valois engine greatly helps, but a major caveat is, could it be scaled-up ? Ariane's Viking is the Valois true heir (with twice the power) but the French gave up pressure-fed technology in favor of a classic turbopump.

Maxwell Hunter recognizes he knows little about pressure-fed rocketry, so he hired America best specialist in the field, the legendary Robert Truax of Sea Dragon fame. "At first the Lockheed hierarchy ordered me to hire Truax, but he refused. He only accepted to be paid as a consultant". This is typical Truax – the man is fiercely independant and refuses to work for either the Government or what he calls "lumbering aerospace giants".

Truax defines himself as a backyard rocketeer churning out rockets out of his home garage. Lockheed reputation did not exactly helped, with the decade-long fuss about their bailout followed by the bribery scandal. Hunter insisted that the space branch of Lockheed had not been tainted by the scandals.

According to Hunter "I learned a lot from Truax. This man and I both pursue the same holy grail, that is, lowering the cost of space transportation. But the similarities stop there – just compare Sea Dragon with my Starclipper shuttle of 1968. I think winged space plane, he thinks big dumb ballistic rocket.

It was Truax that convinced me of DIAGONAL enormous potential. Together we realized that Diagonal might be a very interesting vehicle in the sense that the lower stage was reusable, and the upper Agena a space tug connected to the space station."

If Lockheed is successful in developing the reusable technology, it is expected to significantly reduce the cost of access to space, and change the increasingly competitive market in space launch services. Reusable DIAGONAL could drop the price by an order of magnitude, sparking more space-based enterprise, which in turn would drop the cost of access to space still further through economies of scale.

As of 1978 launch service providers who compete with Lockheed – notably Vought's Scout, but also Atlas, Delta and Titan builders - are not planning to develop similar technology or offer competing reusable launcher options. Lockheed is the only competitor that projected a sufficiently elastic market on the demand side to justify the costly development of reusable rocket technology and the expenditure of private capital to develop options for that theoretical market opportunity. Lockheed is espcifically targeting Vought new Scout-G small launch vehicle.

In order to achieve the full economic benefit of the reusable technology, it is necessary that the reuse be both rapid and complete—without a long and costly refurbishment period. Lockheed Agena (and DIAGONAL) manager Maxwell Hunter gave a realistic appraisal of the potential savings of a reused launch - a 30% saving.

Hunter said that the ability to examine the stage after it has survived the stresses of flight, to put it through qualification and flight acceptance tests to verify and gain confidence in its condition, is the first step toward economical re-use of the launch vehicle. The key to reusability, and lower launch costs, will be quick turnarounds and low refurbishment costs. And that will depend on how the boosters are affected by the stresses of launch, re-entry and landing. The key is how much work is required to return a used rocket to launch readiness.

And that's an unknown, Hunter conceded, adding “I think the business case depends on launching frequently. There has to be costs of refurbishment. Our long-range goal is just to have to pay for the fuel for the second flight.”

“Why is reusing DIAGONAL first stage such a big deal?” Hunter asked “Until now, most of the enormous expense of spaceflight has stemmed from the fact that the rockets carrying payloads to orbit have been thrown away after every flight. Each of these discarded launch vehicles costs many tens of millions of dollars, or more, for just one flight. Imagine how expensive air travel would be if each Boeing or Douglas airliner were used only for one flight and then sent to the junk heap. That absurd waste is the equivalent of what we have been doing in spaceflight since the 1950s. Just recovering only the first stage for reuse on multiple flights would allow us to significantly lower the price of launches for satellites and crewed spacecraft to a level far below what its competitors charge. Our long term goal is to be able to achieve launch costs for around one hundredth of what they currently are.

« If we successfully meet this ultimate challenge, then we are on the verge of the first true Space Age, with all of the spaceflights that have occurred before amounting to an expensive, decades-long process of baby steps leading to this new capability. » Hunter concluded.