Barry Hellman

• Systems Engineer at Lockheed Martin Corporation

This paper investigates using a fully reusable launch vehicle to deliver humanitarian supplies to a crisis region. Missions to three different reference locations were analyzed. The intention of this paper is to examine the feasibly of using this type of launch vehicle to support rapid supply delivery missions. If a fully reusable launch vehicle wh...

This paper presents some approaches towards designing trajectories for hypersonic testing at up to Mach 10 speed using a reusable rocket powered first stage. The motivation behind the paper is the DARPA XS-1 program that is focused on low cost responsive access to space of which the first stage can also be used for hypersonic testing. Trajectories...

Any vehicle which will be subjected to a wide range of flight conditions must have sufficient control authority to maintain vehicle attitude at all times, favoring designs which exhibit small pitching moments at each relevant flight condition. Designing such a vehicle becomes more difficult when the rapid analysis tools common in the early design p...

Partially reusable launch vehicle systems, featuring a reusable first stage and expendable upper stage(s), have been investigated as options for the next generation Air Force launch vehicle to meet future spacelift needs. An important area of research for the reusable first stage is the assessment of the aft end thermal environment in order to dete...

The assumptions associated with modeling the Return to Launch Site (RTLS) trajectory for a Hybrid Launch Vehicle (HLV) are analyzed and documented in this study. The key assumptions that are identified come from the trajectory optimizer behavior. Specifically, the variables controlled by the optimizer, the active constraints, and the overall constr...

The Air Force previously identified the reusable first stage concept as a promising approach to meet its future space lift needs. The reusable first stage consists of an autonomous, reusable, rocket-powered first stage with an expendable upper stage stack. The reusable first stage launches vertically and carries the expendable stack to its staging...

Although the simplifying assumptions of most low-fidelity aerodynamic analysis programs do not hold at certain flight conditions, such as transonic or high-angle flight, higher-fidelity analysis is seldom performed until late in the design process due to time and computational constraints. This may reveal performance deficiencies that must be fixed...

The aerodynamic performance of vehicles which experience uncommon aerodynamic phenomena, such as high angles of attack or nonlinear effects, may not be accurately captured by typical design tools. More complex analysis tools, such as Euler or Navier-Stokes CFD, may be required to accurately predict vehicle behavior. Unfortunately, increased analysi...

During a return to launch site maneuver, a reusable first stage booster experiences a wide range of flight conditions. Its aerodynamic configuration must be a compromise to allow it to successfully glide from supersonic speeds down to landing. Previous studies into similar vehicles have shown that reusable first stages have problems maintaining tri...

This paper presents an aerodynamic comparison of vertical fin placement for a vertical takeoff, horizontal landing Reusable Booster System concept. This analysis was conducted using the CART3D inviscid CFD solver. The three configurations analyzed are a wing tip mounted, split tail fuselage mounted, and a single vertical fuselage mounted. This comp...

Analysis of a Rocket-Based Combined Cycle (RBCC) concept vehicle was performed at the United States Air Force Academy Subsonic Wind tunnel to determine the aerodynamic properties at Mach 0.15, 0.3, 0.4 and 0.5 while simulating the landing stage of flight. Aerodynamic forces acting on the model were determined for different rudder and elevon deflect...

Reusable Boosters Systems (RBS) are potential concept for the future of responsive space access. This project investigates the static stability in the low subsonic flight regimes of a suborbital booster concept during the approach and pre-landing phases of flight prior to landing gear deployment. Subsonic wind tunnel testing is performed on a model...

Reusable first stage rocket boosters have to be designed to maintain trim throughout the flight back to the original launch site. Traditionally, trim analysis takes place after initial design decisions have been made. In order to conduct a conceptual-level trim analysis, higher fidelity tools such as Euler CFD must be used at the conceptual level....

This paper presents the desire by the Air Force to build a Reusable Booster System to provide lower cost and responsive access to space. The various technical challenges that a integrated flight demonstrator can address are presented along with some of the traceability concerns to ensure relevancy to potential operational systems. These technical c...

A Reusable Booster System (RBS) with an expendable upper stage is viewed by the Air Force as being the most likely candidate for the next generation of Ai r Force launch vehicles. A demonstrator program has been proposed to go and test the new technologies that w ill be important to the development of the RBS, inc luding a trajectory employing a ro...

This paper describes the activities between XCOR Aerospace and the Air Vehicles Directorate of the Air Force Research Laboratory in pursuing vehicle design and technologies for operationally responsive spacelift. These activities include a Small Business Innovative Research contract and a cooperative research agreement. Data from aerodynamic analys...

ii AFRL/RBAA, WPAFB, OH 45433 In order to meet goals for responsive access to space, the Air Force has been studying winged reusable booster concepts which are required to perform unpowered landings. The configurations being studied are similar to the Space Shuttle Orbiter in that they are characterized by a large rectangular fuselage cross-section...

Key elements of the needed near-future, integrated, spacefaring logistics infrastructure are space-based, fully-reusable space logistics vehicles to provide transportation for passengers and cargo. This paper addresses the conceptual design of two such reusable spaceships using near-term technologies. The first is a space tug designed to support lo...

This portion of the report documents the results of an experimental program, which focused on pulsed blowing from the trailing edge of a CCW. The main objective of this study was to assess whether pulsed blowing resulted in more, less, or the same amount of radiated noise to the farfield. Results show that a reduction in far-field noise of up to 5...

This conference features the work of authors from: Georgia Tech’s Space Systems Design Lab, Aerospace Systems Design Lab, School of Aerospace Engineering, Georgia Tech Research Institute; NASA’s Jet Propulsion Laboratory, Marshall Space Flight Center, Goddard Space Flight Center, Langley Research Center; and other aerospace industry and academic in...

Issued as final report This item was temporarily removed from SMARTech at the request of the Georgia Tech Research Institute on May 8, 2009.