This document was obtained from Allen W. Sherzer (aws@iti.org). 20 question about the Delta Clipper 1> What is the Delta Clipper? A new spaceship that will take off straight up and land the same way, not gliding but under power, just like the rocketships in the 1950's science-fiction movies. Because of its improved engines, high-tech light-weight materials, and airline-like service procedures, the Delta Clipper could reduce the cost of getting to and from space by 90% or greater. Because it will be certified for flight like an aircraft, it will be able to operate from spaceports located in any state. 2> What will it look like? The production model Delta Clipper will be conical shaped, approximatley 130 feet high and 40 feet accross the base. It will have eight or more rocket engines, providing safe return engine out capability like any airliner. The Delta Clipper will not have wings like the Shuttle but will use small moveable flaps to help maneuver. It will not require strap-on external tanks or boosters. 3> When will it be flying? A 1/3 sized experimental vehicle, the DC-X, is on schedule for launch in April of 1993. The full sized orbital prototype, the DC-Y, could be ready to fly as early as the summer of 1997. 4> Where will it launch from? Test flights will be from White Sands Missile Range, New Mexico, but when the Delta Clipper goes into production any state in the Union will be able to have its own spaceport. Unlike the Shuttle, the Delta Clipper won't need a long runway, huge Vehicle Assembly Building, or Mission Control but only a 200 foot diameter concrete pad, a maintenance hangar, and a hydrogen/oxygen fuel facility. It will use existing global positioning satellites for navigation. 5> What will it cost to design and build the 1st Delta Clipper? The total cost of developing the first flight certified Delta Clipper will be comparable to or less than the development of a new commercial airliner. The cost of building an experimental prototype vehicle to demonstrate the concept and validate the operating and cost goals would be substantially less. 6> What will I have to pay to fly the Delta Clipper? The ticket price for early versions of the Delta Clipper, if it met current cost goals, could be less then the price for a round-the-world cruise on the QE2 ($40,000 to $140,000). A second generation vehicle could further reduce this cost. 7> How dangerous will it be? Once fully operational the Delta Clipper will be safe as flying on a typical commercial airliner. Delta Clipper will have engine out and all altitude abort capability. Plans are to have the Delta Clipper certified by the Department of Transportation, Office of Commercial Space flight. 8> What about air pollution, especially near the ozone layer? The Delta Clipper will burn only hydrogen and oxygen. Its exaust consists primarily of pure water vapor. 9> What about sonic booms and noise when launching or landing? When an airplane flies above the ground faster than sound, it generates a cone-shaped shock wave which we experience as a sonic boom. For this reason, the Concorde jet can't fly supersonically to inland airports in the US. Since the Delta Clipper launches straight up, the sonic boom is largely restricted to the spaceport area. When landing, the Delta Clipper will slow down to sub-sonic speed at about 70,000 feet altitude, thus minimizing the sonic boom to a barely audible level. 10> Who's building it? McDonnell Douglas, under a contract from the Strategic Defense Initiative Organization (SDIO), is building the DC-X for demonstration of the technological and operational feasibility of single stage rockets for supporting either suborbital flights. Based on successful testing of the DC-X, SDIO is interested in developing a fully reusable suborbital rocket to support their numberous suborbital test missions. The design, test results, and concepts will be available to other agencies to develop and demonstrate the orbital vehicle, the DC-Y. We hope to find another "home" for the DC-Y and Delta Clipper in DoD or NASA. 11> How much will the Delta Clipper be able to carry? Two crew members and 10 tons of cargo and/or passengers to Low Earth Orbit or 2 crew members and 5 tons of cargo/passengers to Polar Orbit. 12> Will it be able to fly to the Moon? A Delta clipper derivative vehicle, re-fueled in Low Earth Orbit, would be able to fly to the Moon, land there, and then return to Earth. The modifications required, however, would be substantial. 13> How often will the Delta Clipper be able to fly? The anticipated turn-around time for the Delta Clipper is a maximum of seven days. However, a one day turnaround may be feasible. 14> Why haven't we built a single-stage rocket before? The reason most rockets, including the Shuttle, have parts that drop off (stages) is this: every additional pound of vehicle that we lift all the way to orbit requires additional pounds of fuel. The additional fuel requires a little larger, and heavier, fuel tank, which then requires even more fuel to carry, and so on. There are three ways to deal with this problem: 1) make the rocket so huge (and expensive) that it can carry enough fuel to lift itself all the way to orbit, or 2) toss off empty tanks as you go (the traditional multi-stage method), or 3) make your engines and vehicle structure so efficient and light weight that you don't need to carry huge amounts of fuel or throw away pieces of your ship. This last is the principle behind the Delta Clipper. It is only recently, under such programs as NASP, and aircraft developments that we have sufficently developed and demonstrated light weight materials that will allow the Delta Clipper to work. 15> What if something goes wrong during a flight? Commercial airplanes don't need all their engines to fly safely. The same principle will be used with the Delta Clipper. If there is an engine malfunction during the assent, the Delta Clipper will be capable of either continuing on to orbit orreturning to the spaceport. If the Delta Clipper needs to return from orbit sooner than expected, it will be able to maneuver over 1200 miles to either side. Unlike the Shuttle, which requires a three mile long landing strip, the Delta Clipper will be able to land on nbalmost any reasonably flat spot. 16> Why should I believe all these claims for the Delta Clipper when similar ones were made for the Shuttle twenty years ago? The Shuttle's design was "frozen" in the 1970's. Using the technology available then would have resulted in a SSTO that was extremely large and expensive. A Delta Clipper sized SSTO based on 1970's technology would not have ben able to reach orbit. In the 20 years since then, we have learned a lot about design, light-weight materials, trajectory optimization, avionics, computers, and engine design. In addition, the Delta Clipper is being designed with supportability and operability as priority considerations. For example, the engines on the Delta Clipper won't run at 110% of their design capacity, as the Shuttle's do, so they won't have to be torn down and repaired before each flight. If on-board diagnostic instruments indicate a problem with a Delta Clipper engine or any other component, it is designed so components (called line replaceable units) can be pulled and replaced quickly after landing. 17> Why isn't NASA building the Delta Clipper? The task of proving the technology availability for a single stage rocket vehicle was assigned to SDIO. SDIO with its streamlined management style is an excellent agency for developing and demonstrating new technology initiatives. Once the technology demonstration is completed, the concept will be available for either Department of Defense or NASA to develop an orbital capable Delta Clipper. 18> Why isn't industry building the Delta Clipper? McDonnell Douglas and its teammates have already made a significant investment in the basic technologies and the skills and facilities necessary to develop a SSTO. The government needs to take the next step of funding an experimental prototype vehicle to prove the Delta Clipper's basic concepts and technologies. Once demonstrated, the commercial sector may be interested in investing in an operational system. Such a system could have an enormous impact on the development of space as an commercial market as well as the future of the US space program. 19> What factors could cause the Delta Clipper program to founder? Money: Though the Delta Clipper program is cheaper than many Federal programs, it still is in danger from a budget-conscious Congress who may not be aware of the benefits of the Delta Clipper or who feel the program has no real constituency. We hope to change their minds about this. 20> What can I do to help? Get on our mailing list, be willing to write letters to Congres when asked, learn about the Delta Clipper, ask all your friends to support it too.