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This specification covers quality assurance sampling and testing procedures used to determine conformance to applicable material specifications of corrosion- and heat-resistant steel and alloy forgings.

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.

A 10 KWe dual-mode space power system concept has been identified which is based on INEL's Small Externally-fueled Heat Pipe Thermionic Reactor (SEHPTR) concept. This power system will enhance user capabilities by providing reliable electric power and by providing two propulsion systems; electric power for an arc-jet electric propulsion system and direct thrust by heating hydrogen propellant inside the reactor. The low thrust electric thrusters allow efficient station keeping and long-term maneuvering. The direct thrust capability can provide tens of pounds of thrust at a specific impulse of around 730 seconds for maneuvers that must be performed more rapidly. The direct thrust allows the nuclear power system to move a payload from Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) in less than one month using approximately half the propellant of a cryogenic chemical stage.

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.

Aerospace structures manufacturers find themselves frequently engaged in large-scale 3D metrology operations, conducting precision measurements over a volume expressed in meters or tens of meters. Such measurements are often done by metrologists or other measurement experts and may be done in a somewhat ad-hoc fashion, i.e., executed in the most appropriate method according to the lights of the individual conducting the measurement. This approach is certainly flexible but there are arguments for invoking a more rigorous process. Production processes, in particular, demand an automated process for all such “routine” measurements. Automated metrology offers a number of advantages including enabling data configuration management, de-skilling of operation, real time input data error checking, enforcement of standards, consistent process execution and automated data archiving. It also reduces training, setup time, data manipulation and analysis time and improves reporting.

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.

Two-phase capillary loops are being extensively studied as heat collection and rejection systems for space applications as they appear to satisfy several requirements like low weight, low volume, temperature control under variable heat loads and/or heat sink, operation under on ground and micro gravity conditions, simplicity of mounting and heat transfer through tortuous paths. In 1998–2000 Alenia defined and Lavochkin Association developed the Deployable Radiator on the base of honeycomb panels, axial grooved heat pipes and Loop Heat Pipe. It was designed for on-ground testing.

Most of current jet aircraft circulate fuel on the airframe to match heat loads with available heat sink. The demands for thermal management in wide range of air vehicle systems are growing rapidly along with the increased mission power, vehicle survivability, flight speeds, and so on. With improved aircraft performance and growth of heat load created by Aircraft Mounted Accessory Drive (AMAD) system and hydraulic system, effectively removing the large amount of heat load on the aircraft is gaining crucial importance. Fuel is becoming heat transfer fluid of choice for aircraft thermal management since it offers improved heat transfer characteristics and offers fewer system penalties than air. In the scope of this paper, an AMESim model is built which includes airframe fuel and hydraulic systems with AMAD gearbox of a jet trainer aircraft. The integrated model will be evaluated for thermal performance.

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.

The search for ever-lower emission technology for future generations of aircraft engines is actively progressing on both sides of the Atlantic. Tucked away on a modest-size stand at this year’s Farnborough International Airshow was a highly varied collection of unconventional engine technology displays – a clear indication of radical innovation already being investigated as a part of Ultimate, the European Horizon 2020 research and innovation project.

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.

Aircraft potable (drinking) water systems haven’t changed significantly in the last half-century. These systems consist of cylindrical water tanks pressurized by bleed air from the jet engines, with insulated stainless steel distribution lines. What has changed recently is the increase in the possibility of aircraft picking up contaminated drinking water at foreign and domestic stops. Customer awareness of these problems has also changed - to the point where having reliable drinking water is now a competitive issue among airlines. Old style potable water systems that are used on modern aircraft are high maintenance and exacerbate the growth of microbes because the water is static much of the time. The integrity of some pressurized water tanks are also a concern after years of use. Cost-effective mechanical and biological solutions exist that can significantly reduce the amount of chemicals added and provide good potable water.

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.

The scope of this Standard is the definition of the response of a numerically controlled machine to a valid sequence of records made up of 32 bit binary words or ASCII text strings. The Standard defines the structure of these records and of the 32 bit binary words or ASCII text strings which make up the records. This standard addresses the control of machines capable of performing 2, 3, 4, and 5 axis motion of an active tool (mill, laser, pen, etc.) relative to a part, and those capable of 2 and 4 axis tool motion relative to a rotating part (turning machines), including parallel tool slide sets capable of concurrent (merged) motion.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.