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S J Höeser & S J Höeser, 20 June 2001, "Hearing on Space Launch Initiative: Testimony by Steven Höeser", Before the U.S. House of Representatives. Committee on Science. Subcommittee on Space and Aeronautics.
Also downloadable from on space launch initiative testimony by steven hoeser.shtml

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Hearing on Space Launch Initiative: Testimony by Steven Höeser
Steven J. Höeser
In Brief
Mr. Chairman and distinguished Members of the Committee, I am honored to be called before you to discuss space transportation advancement and our country's Space Launch Initiative program efforts toward that end.

The Space Shuttle, which is the foundation of our national space transportation, is based on a design that was finalized around the close of the Vietnam War. This makes the basic design almost 30 years old. Upgrades to this system abound and several options for shuttle-derived vehicles have been designed and analyzed. Nevertheless, by the time the NASA Space Launch Initiative, or SLI for short, is schedule to produce a new vehicle, the Shuttle airframe will be 40 years old.

As we sit here today, other nations with space capability are investigating reusable launch vehicle or RLV options. Even China is closely monitoring RLV development activities. Our Global competitiveness and leadership RLV efforts to date could be challenged in the not to distant future. A repeat of Europe's Air-Bus or Ariane entry into this global commercial arena could be devastating

It is for these and other reasons I would like to share with the Committee my experience in the RLV field and provide three key observations related to NASA's Space Launch Initiative.

Mr. Chairman, in 1990 I was fortunate to be selected as part of a team that undertook a bold reusable launch vehicle project; The Department of Defense's single-stage-to-orbit program. This project ultimately created the world's first fully reusable rocket dubbed the Delta Clipper Experimental under the management of the DoD's Strategic Defense Initiative Office (SDIO). I apply the term bold in that the SDIO choose to employ an update of the classic rapid program approaches prior to later DoD acquisition reform initiatives. The heritage of the this reusable launch vehicle program can be traced to such aerospace successes as the Polaris and Thor ballistic missile program, the SR-71 Black Bird and U-2 high altitude reconnaissance aircraft to name a few.

The key rule of this classic rapid program approach demands that your primary program objective is to develop a capability. This means that you use today's technology and only dip into the advanced technology bucket as needed. Our DC-X team called this "using technology wisely."

Using technology wisely means that for most of the vehicle's design current technology that is properly engineered should be sufficient. In our case, the contractor's marching orders were to integrate state-of-the-practice aerospace technologies into a reusable rocket design that would demonstrate aircraft-like flight and ground operations.

If the current technology didn't meet the need, the contractors could look to well tested but more expensive emerging technologies. A historical example of an emerging but more expensive technology is graphite-composites. In the early 80's graphite-composites were used only in limited high payoff areas due to their expensive. Today, you see graphite-composites used in everything from umbrella handles to the most advanced military aircraft structures.

We made it clear to the SSTO contractors that high risk advanced technologies should only be used as a last resort. The SSTO contractors that choose concepts that forced them to resort to these advanced technologies were closely scrutinized by the project office and had to provide extremely convincing rational for their use.

INSERT: Perhaps my favorite example in this program of using technology wisely was when McDonnell Douglas DC-X designers chose to use stainless steel piano hinges purchased from a local hardware store for the vehicle's access panels. Better was and is the enemy of good enough for capability-demonstrator programs.

To determine the technology needs for our SSTO rocket designs and to guide our technology investments, we ran an accelerated system engineering concept design study with four contractors. These studies took only 8 months from August of 1990 to April of 1991. I have extracted briefings charts from the start of the program showing our rapid program objectives and from the study conclusions briefing in my submitted testimony for your reference.

These studies concluded that a fully reusable single stage rocket system using existing and emerging early 1990s technology was possible.

With these concept design studies to focus technology investments, and later the applied technology used the first phase DC-X capability demonstrator, our Nation was well on its way to opening space and gaining unchallenged space leadership for decades to come.

Then on the 5th of August 1994, all this changed. A decision was made by former U.S. President Bill Clinton to give NASA the lead for reusable launch vehicles. This decision changed the fundamental nature of the X-33 program from what I call a capability demonstrator focus to a technology centric development.

Whether, as some speculate, this move by the Clinton Administration was a carefully crafted this move by the Clinton Administration to prevent our military from gaining unprecedented space advantage or some other motivation I cannot say for certain. Regardless, this Presidential decision fundamentally changed the course of our Nation's RLV programs from demonstrations of new aerospace capabilities to development projects for advanced technology.

President Clinton's decision was documented in the 1994 National Space Transportation Policy and I quote “gives NASA lead responsibility for technology development for a next-generation reusable space transportation system, such as the single-stage-to-orbit ( SSTO) concept.”

With this direction dutifully and with fervor NASA started planning its RLV program efforts. These plans were built using their Aeronautics and Space Act of 1958, Pub. L. No. 85-568 charter, as amended. This Act states that "the term 'experimental aerospace vehicle' means an object intended to be flown in, or launched into, orbital or suborbital flight for the purpose of demonstrating technologies necessary for a reusable launch vehicle, developed under an agreement between the administration and a developer." Note the key charter direction is to demonstrate technologies not demonstrate capabilities.

From this point on the X-33 and new X-34 program management decisions were made based on developing and testing advanced technology. This essentially guaranteed future NASA RLV efforts would cost more, take longer, and have higher risk than we envisioned in the DoD led DC-X follow-on program.

INSERT: As evidence of the cost impact of managing technology demonstrations verses capability demonstrations, let me indulge in an SSTO/DC-X war story. Prior to letting the DC-X contract our program office conducted a cost estimating study. We used three models, one developed internally, one used by the US Air Force and one from NASA. The results were that our cost estimate based on the rapid program assumptions I described earlier and projected a cost between $60 and $70 million, the Air Force model using standard aerospace procurement practices produced an estimate of $365 million, the NASA model based on highly technology development based shuttle program experience projected the program would cost over $600 million. The actual DC-X program cost through the first test series came in around $65 million.

Unfortunately when the X-33 changed to a technology centric program there never appeared to be a corresponding adjustment to its cost and product expectations. This produced a congenital defect in the resulting program that was apparently never properly diagnosed or treated. On March 1, as we all know these programs were canceled, behind schedule and well over original budget estimates.

My point Mr. Chairman is that changing RLV programs from capability demonstrations that used technology wisely to technology development projects fundamentally changed the character of our Nation's RLV programs. It was not surprise to me that these efforts to longer, cost more, and did not meet original expectations, because they were not the same program.

At this point I would like to state that I believe we should not assigned blame to either the Lockheed Martin, Orbital Sciences or NASA Marshal (Space Flight Center) teams for the X-33 or X-34 program cancellations. NASA dutifully followed their charter to develop and test advanced technology. The contractor teams, like any good commercial business, did what their customers wanted. Perhaps the primary reason I agreed to testify today is because I believe it is vital to our Nation's space leadership that we fix the problem, not fix the blame.

Members of the committee, this leads me to the second of my points today regarding our Country's next generation space transportation developments under the Space Launch Initiative.

It appears that there exists a flaw in the foundational premise driving decisions made in the Space Launch Initiative. This flaw is that the technology is not yet ready to demonstrate fully reusable space transportations.

In a 1 March 2001 press release on the X-33 and X-34 program cancellations Dr. Art Stephenson of Marshal Space Flight Center stated, "We have gained a tremendous amount of knowledge from these X-programs, but one of the things we have learned is that our technology has not yet advanced to the point that we can successfully develop a new reusable launch vehicle that substantially improves safety, reliability and affordability."

My colleague Dr. Stephenson correctly characterized in this same release that the technology development results of the X-33 and X-34 programs did not, in his words, “meet expectations.” But it must be clearly understood that although these programs did not meet expectations, they also showed no conclusive evidence that reusable launch vehicles could not yet be built and demonstrated. All these programs showed was that the advanced subsystem technology that was tested is not ready to be used in a reusable launch vehicle.

In my continued dealings with the industry, I know of a number of companies that have developed and analyzed designs for fully reusable two stage launch vehicle that claim to provide significant cost, safety and operability improvements using today's technologies.

My final point today is really a question. I wonder how the SLI program can know where to make technology invests without an understanding of a target system design? Without this you have no way to trace back customer requirements. In my system design experience and through listening to war stories from some of the legends of America's aerospace successes is that without a system design in mind, what you often end up with is a set of very neat technology that can't be used in anything without being completely re-engineered.

More importantly, when you conduct those system design-engineering studies, it is critical that you disconnect these studies and more importantly the architectures that drive these studies from the technology efforts. To not do so, is to inject almost irresistible temptations on managers to make decisions that favor the technology at the expense of needed capability.

In summary,

First, we should not attribute to malice that which results from existing bureaucracy. Specifically, blaming NASA for not meeting expectations that were built on a capability demonstrator foundation when they only had a technology development mandate serves no useful purpose. If the desire for SLI is to prove capability through a RLV flight demonstrations, then the contractors must be free to choose and integrate what ever technologies exist to get this job done.

Second, we should not eliminate the idea of building a near term RLV capability based on the failure of a few advanced subsystem technologies that failed in the X-33 and X-34 programs. Especially when they may not even be needed to make an integrated RLV system work.

And finally, I believe that it is prudent and critical to conduct independent, and I stress independent, RLV system concept design studies for the SLI program similar to those which proved so successful to the original SSTO/DC-X program. The one change I would recommend in hindsight is that these concept design studies not be limited to single stage designs.

At the very least such studies will provide a basis to prioritize the SLI technology efforts and cut future vehicle development cost and schedule. At the very best, we may find that we our Nation's aerospace engineers can rapidly produce an RLV capability demonstrator that can give us hard flight test data. Which is, after-all, the best basis for an informed decision on next generation reusable launch vehicles.

Thank you and I look forward to your questions.

S J Höeser & S J Höeser, 20 June 2001, "Hearing on Space Launch Initiative: Testimony by Steven Höeser", Before the U.S. House of Representatives. Committee on Science. Subcommittee on Space and Aeronautics.
Also downloadable from on space launch initiative testimony by steven hoeser.shtml

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