Chimera: A Low Cost Solution to Small Satellite Space Access

In the Proceedings of the 17th Annual AIAA/USU Conference on Small Satellites, UT State University Logan, UT, August 11 -14, 2003.The Chimera rocket was designed to enter the small satellite market by offering an affordable and flexible alternative to the Pegasus launch vehicle. A number of design concepts were evaluated, and one was selected to undergo detailed analysis. This included disciplinary analyses in aerodynamics, propulsion, trajectory, aeroheating, structures, weights, operations, and cost. The baseline vehicle, consisting of a Minuteman 2-2 first stage, a PAM-S second stage, and a new third stage carries a 100 and 50 kg payload to a 700 km altitude, at inclinations of 60° and 110° respectively. At this point a Monte Carlo Simulation was performed to determine how well the system met its price goals. The baseline vehicle fails to meet the desired launch price of $5 million to a reasonable confidence level. However, either the implementation of a cost reduction in the cost of the first stage, or the infusion of appropriate structural and propellant technologies in the design of the third stage, help to make the desired launch price viable

Differential and integral calculus,

Part of: Theodore P. Hill collection of early American mathematics books.Mode of access: Internet.Bancroft QA303.S67 1902: Theodore P. Hill collection of Early American Mathematics Books

Aztec: A TSTO Hypersonic Vehicle Concept Utilizing TBCC and HEDM Propulsion Technologies

40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference And Exhibit Fort Lauderdale, FL, July 11 - 14, 2004.The Aztec reusable launch vehicle (RLV) concept is a two-stage-to-orbit (TSTO) horizontal takeoff, horizontal landing (HTHL) vehicle. The first stage is powered by ten JP- 5 fueled turbine-based combined-cycle (TBCC) engines. The second stage is powered by three high energy density matter (HEDM)/liquid oxygen (LOX) staged-combustion rocket engines. The HEDM fuel is a liquid hydrogen-based propellant with a solid aluminum and methane gel additive. Aztec is designed to deliver 20,000 lbs of payload to a 100 nmi x 100 nmi x 28.5 deg orbit due East out of Kennedy Space Center (KSC). The second stage separates at Mach 8 and continues to the target orbit while the first stage flies back to KSC in ramjet mode. For the above payload and target orbit, the gross lift-off weight (GLOW) is estimated to be 690,000 lbs and the total dry weight for both stages is estimated to be 230,000 lbs. Economic analysis indicates that the Aztec recurring launch costs will be approximately 590 dollars per lb. of payload delivered to the target orbit. The total non-recurring cost including design, development, testing and evaluation (DDT&E), acquisition of the first vehicle, and the construction of launch and processing facilities is expected to be 13.6 B dollars. All cost figures are in FY2004 unless otherwise noted. Details of the Aztec design including external and internal configuration, aerodynamics, mass properties, first and second stage engine performance, ascent and flyback trajectory, aeroheating results and thermal protection system (TPS), vehicle ground operations, vehicle safety and reliability, and a cost and economics assessment are provided

Artemis: A Reusable Excursion Vehicle Concept for Lunar Exploration

41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit July 10-13, 2005, Tucson, AZ.Artemis is a reusable excursion vehicle for lunar landing missions. It is intended to transport a notional CEV vehicle from low lunar orbit (LLO) to the lunar surface. It can be reused by refueling the vehicle in LLO. Artemis is nominally sized to carry a 10 MT payload to the lunar surface and then return it to LLO. Artemis is powered by four liquid oxygen and liquid hydrogen fueled RL-10 engines. These RL-10 engines provide the necessary thrust and allow the Artemis lander to complete its nominal mission with two engines inoperative. The Artemis lander has volume margin built into its propellant tanks. This volume margin combined with an innovative cross-feed system allows Artemis to complete its ascent from the lunar surface with a propellant tank failure. This cross-feed system also allows Artemis to adjust the center of gravity (cg) of the vehicle by transferring propellant among the propellant tanks. Artemis lands on the moon with six articulating legs. This provides redundancy against a leg failure on landing and provides Artemis with the ability to land on uneven terrain. This vehicle is designed to be launched by a heavy-lift evolved expendable launch vehicle (EELV). This design constraint results in the distinct shape of the lander. Artemis is launched as a compact cylinder in the EELV payload shroud, and then autonomously assembles itself via robotic arms similar to those currently used by the shuttle program. Details of the conceptual design process used for Artemis are included in this paper. The disciplines used in the design include configuration, propulsion design and selection, trajectory, mass properties, structural design, cost, operations, and reliability and safety. Each of these disciplines was computed using a conceptual design tool similar to that used in industry. These disciplines were then combined into an integrated design team process and used to minimize the gross weight of the Artemis. Once the design process was completed, a parametric Excel based model was created from the point design. This model can be used to resize Artemis for changing system metrics (such as payload) as well as changing technologies. The Artemis recurring and non-recurring costs were also computed. The total development cost including the design, development, testing and evaluation (DDT&E) cost is $2.17 B FY'04. The theoretical first unit (TFU) cost is$303 M FY'04. Trade studies on life cycle costs (LCC) vs. fuel cost to LLO as well as flight rate are also discussed. A summary of design disciplines as well as the economic results are included

Chimera - A Low Cost Solution to Small Satellite Space Access

The Chimera rocket was designed to enter the small satellite market by offering an affordable and flexible alternative to the Pegasus launch vehicle. A number of design concepts were evaluated, and one was selected to undergo detailed analysis. This included disciplinary analyses in aerodynamics, propulsion, trajectory, aeroheating, structures, weights, operations, and cost. The baseline vehicle, consisting of a Minuteman 2-2 first stage, a PAM-S second stage, and a new third stage carries a 100 and 50 kg payload to a 700 km altitude, at inclinations of 60° and 110° respectively. At this point a Monte Carlo Simulation was performed to determine how well the system met its price goals. The baseline vehicle fails to meet the desired launch price of $5 million to a reasonable confidence level. However, either the implementation of a cost reduction in the cost of the first stage, or the infusion of appropriate structural and propellant technologies in the design of the third stage, help to make the desired launch price viable

Flight System Options for a Long Duration Mars Airplane

3rd AIAA "Unmanned Unlimited" Technical Conference Chicago, IL, Sept. 20-23, 2004.The goal of this study was to explore the flight system options for the design of a long endurance Mars airplane mission. The mission model was built in the design framework ModelCenter and a combination of a hybrid and user-driven fixed point iteration optimization method was used to determine the maximum endurance solution of each configuration. Five different propulsion systems were examined: a bipropellant rocket, a battery powered propeller, a direct methanol fuel cell powered propeller, and beamed solar and microwave powered propeller systems. Five airplane configurations were also studied. The best configuration has a straight wing with two vertical tails. The direct methanol fuel cell proved to be the best onboard power system for a long endurance airplane and the solar beamed power system showed potential for indefinite flight. The combination of the best configuration and the methanol fuel cell resulted in an airplane capable of cruising for 17.8 hours on Mars

Modeling Approach for Analysis and Optimization of a Long-Duration Mars Airplane

AIAA MA&O Conference Albany, NY, May 30-June 1, 2004.The goal of this study was to determine the best system level modeling tool for the design of a long endurance Mars airplane mission, and to use this tool to determine the best configuration for the aircraft. The mission model was built in the design framework ModelCenter. User-driven fixed point iteration (FPI), optimizer based decomposition (OBD) and a hybrid method were implemented. Convergence difficulties were discovered in the OBD and hybrid methods. The user-driven FPI method produced the most reliable results, but required the most time. A combination of the hybrid and user-driven FPI methods were used to perform a technology study in which five different propulsion systems were examined: a bipropellant rocket, a battery powered propeller, a direct methanol fuel cell powered propeller, and beamed solar and microwave powered propeller systems. The direct methanol fuel cell proved to be the best onboard power system for a long endurance airplane and the solar beamed power system showed potential for indefinite flight