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An integration study was performed coupling an SP-100 reactor with either a Brayton or Stirling power conversion subsystem. A power level of 100 kWe was selected for the study. The power system was to be compatible with both the lunar and Mars surface environment and require no site preparation. In addition, the reactor was to have integral shielding and be completely self-contained, including its own auxiliary power for start-up. Initial reliability studies were performed to determine power conversion redundancy and engine module size. Previous studies were used to select the power conversion optimum operating conditions (ratio of hot-side temperature to cold-side temperature). Results of the study indicated that either the Brayton or Stirling power conversion subsystems could be integrated with the SP-100 reactor for either a lunar or Mars surface power application.

The Cardinal is a Super Short Takeoff and Landing (SSTOL) aircraft, which is designed to fulfill the desire for center-city to center-city travel by utilizing river “barges” for short takeoffs and landings to avoid construction of new runways or heliports. In addition, the Cardinal will fulfill the needs of the U.S. Navy for a Carrier On-board Delivery (COD) aircraft to replace the C-2 Greyhound. Design requirements for the Cardinal included a takeoff ground roll of 300 ft, a landing ground roll of 400 ft, cruise at 350 knots with a range of up to 1500 nm with reserves, payload of 24 passengers and baggage for a commercial version or a military version with a 10,000 lb payload, capable of carrying two GE F110 engines for the F-14D, and a spot factor requirement of 60 feet by 29 feet.

Preliminary results from testing of 26 X 6.6 radial-belted and bias-ply aircraft tires at NASA Langley's Aircraft Landing Dynamics Facility (ALDF) are reviewed. These tire tests are part of a larger, on going joint NASA/FAA/Industry Surface Traction and Radial Tire (START) Program involving three different tire sizes. The 26 X 6.6 tire size evaluation includes cornering performance tests throughout the aircraft ground operational speed range for both dry and wet runway surfaces. Static test results to define 26 X 6.6 tire vertical stiffness properties are also presented and discussed.

Sundstrand has been investigating 270-Vdc/hybrid 115-Vac electrical power generating systems (EPGS) technology in preparation for meeting the electrical power generating system (EPGS) requirements for future aircraft (1). Systems such as the one being investigated are likely to be suitable for the More-Electric Aircraft (MEA) concepts presently under industry and military study. The present Sundstrand single-channel testbed is being further expanded to better understand the electrical system performance characteristics and power quality requirements of an MEA in which traditional mechanical subsystems are replaced by those of a “more-electric” nature. This paper presents the most recent Sundstrand 270-Vdc system transient performance data, and describes the modifications being made to the 270-Vdc/hybrid 115-Vac testbed.

Vertical-Junction-Field-Effect-Transistors (VJFETs) are currently the most mature SiC devices for high power/temperature switching. High-voltage VJFETs are typically designed normally-on to ensure voltage control operation at high current-gain. However, to exploit the high voltage/temperature capabilities of VJFETs in a normally-off high-current voltage-controlled switch, high-voltage normally-on and low-voltage normally-off VJFETs were connected in the cascode configuration. In this paper, we review the high temperature DC characteristics of VJFETs and 1200 V normally-off cascode switches. The measured parameter shifts in the 25°C to 300°C temperature range are in excellent agreement with theory, confirming fabrication of robust SiC VJFETs and cascode switches.

The experimental procedure employed to define the natural modes of vibration of the 747 Shuttle Carrier Aircraft and Space Shuttle Orbiter mated configuration is described. A discussion of test results and comparison to structural analysis results is also included. Random transient signals were used as inputs to electromagnetic shakers to provide excitation to the mated vehicle test configuration. Acceleration signals were processed via the Fast Fourier Transform algorithm. Magnitude and phase transfer functions were formed and processed to produce modal frequencies, damping, and modal displacements.

The 757/767 Flight Management System provides the initial operational implementation of an integrated guidance, control and display equipments based upon digital technology for commercial transport airplanes. The applied equipments are based upon the new ARINC 700 series characteristics developed by the Industry over the past five years. These characteristics were developed on the basis of limited operational experience with selected elements of the system and upon R&D efforts within the Industry. The System features automatic/manual flight profiles for optimum economics, all weather landing including rollout guidance, electronic primary flight instruments based on color (shadow mask) CRTs, inertial attitude/velocity reference based upon laser gyros, improved caution/warning and other improved performance/functional features. The system also provides significant improvements in line and shop maintenance features.

In the course of CRYOSYSTEM phase B (development phase) financed by the European Space Agency, AIR LIQUIDE (France) and Astrium Space Infrastructure (Germany) have developed an optimized design of a −183°C freezer to be used on board the International Space Station for the freezing and storage of biological samples. The CRYOSYSTEM facility consists of the following main elements: - the CRYORACK, an outfitted standard payload rack (ISPR) accommodating up to three identical Vial Freezers - the Vial Freezer, a dewar vessel capable of fast and ultra-rapid freezing, and storing up to approximately 900 vials below −183°C; the dewar is cooled by a Stirling machine producing > 6 W at 90 K. The Vial Freezer is operational while accommodated in the CRYORACK or attached to the Life Science Glovebox (LSG). One CRYORACK will remain permanently on-orbit for several years while four Vial Freezers and two additional CRYORACKs support the cyclic upload/download of samples.

Some of the methods used for experimental detection and examination of wake vortices are presented. The aim of the article is to provide the reader a brief overview of the available methods. The material is divided into two major sections, one dealing with methods used primarily in the laboratory, and the second part devoted to those used in field operations. Over one hundred articles are cited and briefly discussed.

Europe has embarked on a new programme of space exploration involving the development of rover, lander and probe missions to visit planets, moons and near Earth objects (NEOs) throughout the Solar System. Rovers and landers will require testing under simulated planetary, and NEO conditions to ensure their ability to land on and traverse the alien surfaces. ESA has begun work on a building project that will provide an enclosed and controlled environment for testing rover and lander functions such as landing, mobility, navigation and soil sampling. The facility will first support the European ExoMars mission due for launch in 2013. This mission will deliver a robotic rover to the Martian surface. This paper, the first of several on the project, gives an overview of its design configuration and construction phasing. Future papers will cover its applications and operations.

Airline tenants at Dallas/Fort Worth International Airport (DFW Airport) use deicing/anti-icing chemicals, as may be needed, to maintain wintertime operations. DFW Airport has implemented best management practices for pollution prevention measures relating to deicing/anti-icing activities. However, as the planes leave the deicing pads, deicing/anti-icing fluids can drip from the planes onto the runways, taxiways, and ramp areas. As planes take off, the fluids can also shear off onto Airport property. During winter storm events, these deicing/anti-icing fluids are flushed off the runways, etc., with the stormwater. Stormwater containing deicing/anti-icing fluids can discharge through outfalls into Trigg Lake located in the southwestern part of the DFW Airport property.

The goal of the Controlled Ecological Life Support System (CELSS) Program at NASA Ames Research Center is to develop life support systems that will support humans during long duration space missions. These life support systems must be able to regenerate air and water for the crew while at the same time minimize power consumption and disposables. A series of microgravity compatible subsystems will be required to meet this goal. However, operating these subsystems in microgravity raises serious technical problems. Existing subsystems may need to be refined or new technologies may need to be developed to overcome these problems. To evaluate and test these new subsystems and technologies, a series of KC-135 precursor flights are being flown by members of the CELSS Flight Group. One of the key elements in these flight activities is the free floating testbed (FFTB).

The vision of SESAR is to integrate and implement new technologies to improve air traffic management (ATM) performance. Enhanced automation and new separation modes characterize the future concept of operations, where the role of the human operator will remain central by integrating more managing and decision-making functions. The expected changes represent challenges for the human actors in the aircraft and on ground and must be taken into account during the development phase. Integrating the human in the ATM system development starting from the early design phase is a key factor for future acceptability. This paper describes the adaptation of currently applied Cockpit Human Factors processes in order to be able to design the aircraft for the future ATM environment.

The objectives are to compare different psychological methods used to assess the evolution of the interrelations inside the crew and the relationships between the crew and the outside in a sixty days isolation/confinement's simulation. After presenting each method, results are compared. The discussion try to point out if these methods are equivalent or if they are complementary. The specificity of each method is shown and conclusions try to associate some methods with specific scientific goals.

Two turbulence models have been studied to determine which of the models should be used in further Computational Fluid Dynamics (CFD) research. A zero-equation turbulence model, Baldwin-Lomax (B-L), is easy to use, requires no history of the flow, and requires little in the way of additional computations or additional computer memory space [1]. A two-equation k-ε model, Yang-Shih (Y-S), is more difficult to implement, does require flow history, and requires many more computations and much more computer space; however, it is potentially more accurate than the B-L model [2]. Using both Navier-Stokes (NS) and Parabolized Navier-Stokes (PNS) solvers, the two models and their codes were validated against the testbed of the Wright Laboratory (WL) Mach 12 wind tunnel nozzle.

The Orion Crew and Service Modules are often compared to the Apollo Command and Service Modules due to their similarity in basic mission objective: both were dedicated to getting a crew to lunar orbit and safely returning them to Earth. Both spacecraft rely on the environmental control, life support and active thermal control systems (ECLS/ATCS) for the basic functions of providing and maintaining a breathable atmosphere, supplying adequate amount of potable water and maintaining the crew and avionics equipment within certified thermal limits. This assessment will evaluate the driving requirements for both programs and highlight similarities and differences. Further, a short comparison of the two system architectures will be examined including a side by side assessment of some selected system's hardware mass.

This work presents a comprehensive numerical model for ice accretion and Ice Protection System (IPS) simulation over a 2D component, such as an airfoil. The model is based on the Myers model for ice accretion and extended to include the possibility of a heated substratum. Six different icing conditions that can occur during in-flight ice accretion with an Electro-Thermal Ice Protection System (ETIPS) activated are identified. Each condition presents one or more layers with a different water phase. Depending on the heat fluxes, there could be only liquid water, ice, or a combination of both on the substratum. The possible layers are the ice layer on the substratum, the running liquid film over ice or substratum, and the static liquid film between ice and substratum caused by ice melting. The last layer, which is always present, is the substratum. The physical model that describes the evolution of these layers is based on the Stefan problem. For each layer, one heat equation is solved.

This paper presents an overview of the Computer Aided Systems Engineering and Analysis (CASE/A)-ECLSS series which is designed as a generalised ECLSS design and analysis package. This system was developed under NASA MSEC contract NAS8-36407 to meet the Systems Analysis requirements of the Space Station ECLSS. The Space Station represents an order of magnitude increase in complexity over current Spacecraft technologies and will seriously tax current analysis techniques. This program is capable of simulating atmospheric revitalization systems, water recovery and management systems, and single phase active thermal control systems. The program evolved from both the G189A and the SINDA programs and shares the G189A architectural concepts. The designer/ analysis interface is graphics based and allows the designer to build a model by constructing a schematic of the system under consideration.