The Shuttle's two-dimensional entry trajectory planning method is extended to threedimensions. Both angle of attack and angle of bank variations are used to control the entry trajectory. The trajectory planning is done with a third-order system of di erential equations using the drag and lateral accelerations as intermediate controls. The reducedorder planning problem is solved as an optimal co...

Abstract This work is focused on evaluating the structural design of innovative reusable micro launcher MESO, originated from RRTB, a funded project by EU. The efficiency MESO evaluated in association with its mass budget, which based project’s early adopted requirements. In this particular loop, reusability concept intergraded implementing fail-safe approach, considering exclusive use high TRL...

Analyzing systems by means of simulation is necessarily a time consuming process. This becomes even more pronounced when models of multiple systems must be compared. In general, and even more so in today’s fast-paced environment, competitive pressure does not allow for waiting on the results of a lengthy analysis. That competitive pressure also makes it more imperative that the processing perfo...

The NASA Langley Research Center has been performing studies to address the feasibility of various single-stage to orbit concepts for use by NASA and the commercial launch industry to provide a lower cost access to space. Some work on the conceptual design of a typical lifting body concept vehicle, designated VentureStarTM has been conducted in cooperation with the Lockheed Martin Skunk Works. ...

In the application of adaptive flight control, significant issues arise due to vehicle input characteristics such as actuator position limits, actuator position rate limits, and linear input dynamics. The concept of modifying a reference model to prevent an adaptation law from “seeing” and adapting-to these system characteristics is introduced. A specific adaptive control method based on this c...

This paper presents an application of the nonlinear optimal control techniques to the design of launch vehicle autopilots. The optimal control is given by the solution to the Hamilton-Jacobi-Bellman (HJB) equation, which in this case cannot be solved explicity. A method based upon Successive Galerkin Approximation (SGA), is used to obtain an approximate optimal solution. Simulation results invo...

Dual infection of mice with murine sarcoma virus (Moloney) [MSV(M)] and Rauscher leukemia virus (RLV) resulted in an enhanced MSV(M) infection, reflected by increased mortality with tumor. Significant increases in tumor incidence, induced by low concentrations of MSV(M) when inoculated into RLV-infected mice, demonstrated that RLV enhanced MSV(M) oncogenicity. Temporal studies indicated that RL...