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The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.

Carbon fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This paper describes eleven design rules originating from different guidelines that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components and access for non-destructive testing (NDT). To verify the technical content and ensure practicability, the rules were developed by, inter alia, studying literature and performing case studies at SAAB Aerostructures.

The EUROMIR-95 flight was selected as model for the HUBES experiment: a similar duration (135 days), a similar crew (3 men), similar schedule organisation (8 hours work, 8 hours sleep, 8 hours off-duties), similar workload for the crew and the mission control (performance of scientific experiments), similar setup for communication and data processing, and similar layout of the MIR station, as the simulation was performed in the MIR simulator located at the Institute for BioMedical Problems (IBMP) in Moscow. The Scientific Programme of HUBES had been elaborated by integration of 31 experiments from more than 80 research proposals from Principal Investigators from Europe, USA and Russia, in domains of Physiology, Psychology, Operations and Technology.

The 1977 Clean Air Act Amendments allow the U.S. Environmental Protection Agency to set high altitude emission standards for 1981-83, but specify that any such standards may not be more stringent than comparable sea level standards -- relative to 1970 emission levels. Since available high altitude emission data from 1970 models were incomplete and controversial, the Motor Vehicle Manufacturers Association contracted with Automotive Testing Laboratories, Inc. to test a fleet of 25 1970 cars. Results of the test program showed average increases in emissions at Denver's altitude, compared to sea level, to be about 30% for evaporative HC, 57 to 60% for exhaust HC, 215 to 247% for CO and -46 to -47% for NOx. Corresponding HC and CO exhaust emission baselines would be 6.4 to 6.6 and 108 to 118 g/mi respectively.

The paper describes a numerical study, supported by experiments, on light aircraft 2-Stroke Direct Injected Diesel engines, typically rated up to 110 kW (corresponding to about 150 imperial HP). The engines must be as light as possible and they are to be directly coupled to the propeller, without reduction drive. The ensuing main design constraints are: i) in-cylinder peak pressure as low as possible (typically, no more than 120 bar); ii) maximum rotational speed limited to 2600 rpm. As far as exhaust emissions are concerned, piston aircraft engines remain unregulated but lack of visible smoke is a customer requirement, so that a value of 1 is assumed as maximum Smoke number. For the reasons clarified in the paper, only three cylinder in line engines are investigated. Reference is made to two types of scavenging and combustion systems, designed by the authors with the assistance of state-of-the-art CFD tools and described in detail in a parallel paper.

In part two of a two-part series, Richard Gardner discusses various aerospace propulsion innovations and continued work by aerospace engineers and scientists to advance aircraft engine technologies to increase efficiency and lower emissions.

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.

Ultrasound is attractive for medical imaging in space because scanners can be small, lightweight, low power, and have minimal electromagnetic emissions. In addition, unlike conventional 2-D ultrasound. 3-D ultrasound allows an operator with no diagnostic skills to collect high-quality scans that can be interpreted by a remote expert. This allows 3-D ultrasound to be used effectively in remote locations. These capabilities are illustrated by the MUSTPAC-1, a portable 3-D ultrasound telemedicine system recently developed for the U.S. military. Design, implementation, and field experiences with the MUSTPAC-1 are discussed, and extensions for use in space are proposed.

This paper discusses five different methods for measuring the gas stream temperature from a burner using a hydrocarbon fuel, air, and oxygen. Tests were made with a single shielded BeO probe, a bare wire iridium -- 60% rhodium/iridium couple, a tantalum triple shielded platinum -- 10% rhodium/platinum thermocouple, the sodium line reversed technique, and a watercooled total enthalpy probe. The most serviceable system proved to be the bare wire iridium -- 60% rhodium/iridium couple, particularly for carrying out stream surveys where relative, rather than true temperatures, are of primary concern. More study is needed to establish a system for determining the true stream temperature.

The objective of this project was to replace electromechanical power line contactors with a Static Transfer Switch (STS) to improve the transfer of electrical power between aircraft generators and decrease required maintenance. The switch requirements include high reliability, lightweight, and high speed (less than 15mS) power transfer. An STS can shorten the bus transfer time to less than the “ride-through” of aircraft electronic loads and therefore have the ability to control and transfer electrical power while maintaining critical mission requirements. The content of this paper and presentation will discuss the initial problem, the research and development approach, design, and initial testing of the STS.

A 500 hours endurance test was performed with a heavy-duty engine (Euro IV); MAN type D 0836 LFL 51 equipped with a PM-Kat®. As fuel 100% biodiesel was used that met the European specification EN 14214. The 500 hours endurance test included both the European stationary and transient cycle (ESC and ETC) as well as longer stationary phases. During the test, regulated emissions (carbon monoxide, nitrogen oxides, hydrocarbons and particulate matter), the particle number distribution and the aldehydes emission were continuously measured. For comparison, tests with fossil diesel fuel were performed before and after the endurance test. During the endurance test, the engine was failure-free for 500 hours with the biogenic fuel. There were almost no differences in specific fuel consumption during the test, but the average exhaust gas temperature increased by about 15°C over the time. Emissions changed only slightly during the test.

Unguided sounding rockets, also known as sub-orbital rockets, are vehicles that carry scientific experiments and/or sensors to collect data during their trajectory. These rockets lack active control but are capable of traversing the Earth’s atmosphere. It is crucial to thoroughly analyze the flight parameters during the preliminary design phase. The Open Rocket flight simulation software, developed by Sampo Niskanen, is a widely used open-source project. However, it has some simplifications in comparison to its documentation. It does not specify the calculations of critical parameters required for the rocket’s stability during its flight. Additionally, it does not calculate data related to dynamic stability, which encompasses the system’s ability to make disturbances corrections during the rocket’s trajectory. Consequently, this study presents a flight simulation of a rocket with 6 degrees of freedom using Matlab/Simulink.

This handbook is intended to assist the user to understand the ANSI/EIA-649B standard principles and functions for Configuration Management (CM) and how to plan and implement effective CM. It provides CM implementation guidance for all users (CM professionals and practitioners within the commercial and industry communities, DoD, military service commands, and government activities (e.g., National Aeronautics and Space Administration (NASA), North Atlantic Treaty Organization (NATO)) with a variety of techniques and examples. Information about interfacing with other management systems and processes are included to ensure the principles and functions are applied in each phase of the life cycle for all product categories.

This paper describes ongoing research into Metrology-integrated robot control. The research is a part of an ongoing EU funded aircraft industry project – ADFAST*. The ADFAST project tries to implement the use of industrial robots in low-volume production, high-demand-on-accuracy operations and for dynamic force compensation. To detect and compensate deflection in industrial robots during a process, the robot uses a metrology system. The metrology system supervises the tool center point of the robot as it executes its processes. Leica has recently released a new metrology system; the LTD800, which measures distances with laser interferometry and can simultaneously measure orientation of targets, through photogrammetry, using an additional camera on top of the measuring unit. This paper will describe theory and results from tests performed on integrating the LTD800 with the robot.

In 1995, the Naval Research Laboratory (NRL) began a program to investigate whether a 90 Ah dependent pressure vessel (DPV) NiH2 battery pack could be a lower volume replacement for a 90 Ah NiH2 IPV spacecraft battery. Nickel Hydrogen (NiH2) dependent pressure vessel (DPV) battery cells are presumed to offer all the features of the NiH2 IPV battery cell with considerably less volume. To achieve this reduction in volume, the DPV cell utilizes a canteen shaped pressure vessel with reduced thickness wall, flat sides and curved ends. The cells can be packaged similar to prismatic nickel cadmium battery cells. Moreover, like NiCd cells, a fully charged DPV cell must rely upon an adjacent battery cell or structure for support and to maintain pressure vessel integrity. Seventeen 90 Ah NiH2 DPV cells were delivered to NR in 1998 for qualification tests. An eleven-cell half battery pack was manufactured and tested to validate the advantages of the DPV design.

The 912 engine is a well known 4-cylinder horizontally opposed 4-stroke liquid-/air-cooled aircraft engine. The 912 family has a strong track record: 40 000 engines sold / 25 000 still in operation / 5 million flight hours annually. 88% of all light aircraft OEMs use Rotax engines. The 912iS is an evolution of the Rotax 912ULS carbureted engine. The “i” stands for electronic fuel injection which has been developed according to flight standards, providing a better fuel efficiency over the current 912ULS of more than 20% and in a range of 38% to 70% compared to other competitive engines in the light sport, ultra-light aircraft and the general aviation industry. BRP engineers have incorporated several technology enhancements. The fully redundant digital Engine Control Unit (ECU) offers a computer based electronic diagnostic system which makes it easier to diagnose and service the engine.

Bioregenerative life support systems have the potential to reduce the need for resupply from Earth for extraterrestrial habitats. The proposed advanced life support system, developed by an international and interdisciplinary team, is an innovation combination of current and near term research and technologies. The system combines physico-chemical methods with algae, aquaculture and higher plants to purify wastes and provide consumables. A closed loop percentage of 90-95% percent is expected with additional supplies for dietary supplement and maintenance. The information gained from the development of the proposed artificial biosphere can also help to solve sustainability problems currently prevalent on Earth.

With reusability accepted as a means of reducing operating costs, the size of the initial investment (research and development) is likely to determine the choice for the next generation boosters. High volume utilisation lifting bodies propelled by LH/LOX rockets in a vertical take-off mode are shown to be superior to several other concepts. This is largely due to the low manufactured weight without undue complexity or use of exotic materials, leading to low R&D and low unit cost. Even lower costs can be shown for a modular concept (MUSTARD) in which basically identical lifting bodies units are utilised as both boosters and spacecraft. The concept is shown to be feasible, and progress on some aspects of the associated structural analysis is described.

As humans move into outer space, need for air, clean water and food require that green plants be grown within all planetary colonies. The complexities of ecosystems require a sophisticated understanding of the interactions between the atmosphere, all nutrients, and life forms. While many experiments must be done to find the relationships between mass flows and chemical/energy transformations, it seems necessary to develop generalized models to understand the limitations of plant growth. Therefore, it is critical to have a robust modelling capability to provide insight into potential problems as well as to direct efficient experimentation. Last year we reported on a simple leaf model which focused upon the mass transfer of gases, radiation/heat balances, and the production of photosynthetically produced carbohydrate. That model indicated some of the plant processes which had to be understood in order to obtain parameters specific for each species.

An optical sensor for the detection of carbon dioxide concentrations and stable isotope ratios is described. Either a continuous wave, fiber-coupled distributed feedback laser or an external cavity laser is used to pump an optical cavity absorption cell in cw-Cavity Ringdown Spectroscopy (cw-CRDS). This technique exploits the sensitivity enhancements provided by the long effective pathlength from the optical cavity created between two highly reflective mirrors (R>0.9999). The inherently high precision of the technique combined with its rapid data throughput allows for reliable measurements of both concentration and the isotopic composition of the sampled carbon dioxide. Data collected using a prototype of this sensor could be useful for monitoring module occupancy, crew health (through breath tests), and plant growth chambers.