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The Air Force has an initiative entitled, Subsystem Integration Technology (SUIT) to develop and demonstrate integration technology as applied to the traditional aircraft utility subsystems. Utility subsystems perform functions such as auxiliary power generation, environmental control, and fuel management. Commonly these different subsystems are developed independently and then interfaced when building a particular flight vehicle. The SUIT program considers all functions accomplished by the traditional utility subsystems to be responsibilities of a single entity called a utility suite. This suite is designed with overall vehicle level performance objectives rather than trying to maximize the performance of individual functions and is not bound to maintaining the traditional allocation of functions among the hardware labeled as fuel management, environmental control, or secondary power.

This paper describes air breathing reusable space launch vehicle concepts intended to provide very rapid response launch of 10,000 lb polar orbit payloads (or approximately 20,000 lbs Eastern). The vehicles are two-stage, with the first stage employing turboramjet propulsion and the second stage using rockets. Liquid oxygen (LOX) for the second stage is collected during first stage ascent using technologies from the original Aerospaceplane work along with recent improvements. No LOX is carried at takeoff, thus eliminating the need for LOX ground servicing facilities. A dual fuel approach, liquid hydrogen and ambient storable hydrocarbon fuel (LH2 and JP), uses JP fuel for first stage acceleration and second stage rocket ascent. LH2 in the amount just sufficient to condense and collect second stage LOX, is the only cryogenic fluid that is loaded on the vehicle at takeoff.

Laser Velocimetry (LV) is often utilized as an off-the-shelf nonintrusive measurement technique for low speed, steady state flows. However, in complex, supersonic flows, the application of LV becomes highly specialized. Setups must often contend with limited optical access, poor signal-to-noise ratios, and limited tunnel run times. Furthermore, seeding particles must survive large ranges of flow temperatures and pressures, and extensive data analysis and interpretation are required to ascertain whether measured particle velocities are representative of the fluid flow. Several examples of LV studies in the supersonic regime demonstrate recent advancements and the current state-of-the-art of this measurement technique. Results are included from three wind tunnel facilities, operating at freestream Mach numbers of 1.9, 3, and 6, and track an evolution of applications from flat plate boundary layers to the complex flowfield of a supersonic inlet.

The Photovoltaic Array Space Power Plus Diagnostics flight experiment (PASP+) subsumes twelve solar array modules which represent the state of the art in the space photovoltaic array industry. Each of the twelve modules individually feature specific photovoltaic technologies such as advanced semiconductor materials, multi-bandgap structures, lightweight array designs, advanced interconnect technologies, or concentrator array designs. This paper will describe each module in detail including the configuration, components, materials, anticipated on orbit performance, and some of the aspects of each array technology. The layout of each module and the photovoltaic cell or array cross section will be presented graphically. A discussion on the environmental constraints and materials selection will be included as well as a delineation of the differences between the modules and the baseline array configuration in its intended application.

The Air Force has sponsored a program at the University of Kentucky which will lead to a better understanding of the thermal and fluid instabilities during blowdown of supercritical fluids at cryogenic temperatures. An integral part of that program is the design and construction of a hydrogen test facility. This paper describes the design specifications and construction of that hydrogen test facility. This facility will be capable of providing supercritical hydrogen at 30 bars and 35 K at a maximum flow rate of 0.1 kg/s for 90 seconds. Also presented here is an extension of this facility to accommodate the use of supercritical helium.