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Modern aircraft are aerodynamically designed at the edge of flight stability and therefore require high-response-rate flight control surfaces to maintain flight safety. In addition, to minimize weight and eliminate aircraft thermal cooling requirements, the actuator systems have increased power-density and utilize high-temperature components. This coupled with the wide operating temperature regimes experienced over a mission profile may result in detrimental performance of the actuator systems. Understanding the performance capabilities and power draw requirements as a function of temperature is essential in properly sizing and optimizing an aircraft platform. Under the Air Force Research Laboratory's (AFRL's) Integrated Vehicle and Energy Technology (INVENT) Program, detailed models of high performance electromechanical actuators (HPEAS) were developed and include temperature dependent effects in the electrical and mechanical actuator components.

Defining a process for integrating human modeling within the design and verification activities of the International Space Station (ISS) has proven to be as important as the simulations themselves. The process developed (1) ensured configuration management of the required digital mockups, (2) provided consistent methodology for simulating and analyzing human tasks and hardware layout, (3) facilitated an efficient method of communicating design requirements and relaying satisfaction of contract requirements, and (4) provided substantial cost savings by reducing the amount of late redesign and expensive mockup tests. Human simulation is frequently the last step in the design process. Consequently, the influence it has on product design is minimal and oftentimes being used as a post-design verification tool.

The paper presents the results of a CFD study for predictions of ventilation characteristics and convective heat transfer within the Shuttle Orbiter middeck cabin in the presence of seven suited crewmember simulation and Individual Cooling Units (ICU). For two ICU arrangements considered, the thermal environmental conditions directly affecting the ICU performance have been defined for landing operation. These data would allow for validation of the ICU arrangement optimization.

In August 1997 NASA/Marshall Space Flight Center (MSFC) began a test with the objective of monitoring the growth of microorganisms on material simulating the surface of the International Space Station (ISS) Temperature and Humidity Control (THC) Condensing Heat Exchanger (CHX). The test addressed the concerns of potential uncontrolled microbial growth on the surface of the THC CHX subsystem. For this study, humidity condensate from a closed manned environment was used as a direct challenge to the surfaces of six cascades in a test set-up. The condensate was collected using a Shuttle-type CHX within the MSFC End-Use Equipment Testing Facility. Panels in four of the six cascades tested were coated with the ISS CHX silver impregnated hydrophilic coating. The remaining two cascade panels were coated with the hydrophilic coating without the antimicrobial component, silver. Results of the fourteen-month study are discussed in this paper.

Choosing the best approach to meet waste processing requirements for long duration space missions should be based on objective selection criteria that provide for subsystem operational availability at the lowest mission cost. Suitable criteria would include robustness, safety, and the minimization of mass, volume, power, cooling, crew time, and resupply requirements for the candidate technologies. The best candidate technologies based on data from historical missions and preliminary data from the Solid Waste Processing and Resource Recovery Workshop (SWPRRW) have been evaluated for cost effectiveness in processing crew waste loads as defined by identified waste models. Both PC and biological approaches were considered for each of three missions: the ISS mission, a Mars transit mission, and a “concentrated exploration” mission for the Mars surface. Results of this analysis are consistent for all three missions considered.

The Centrifuge Accommodation Module (CAM) is designed to be one of the modules of the International Space Station (ISS) for performing on-orbit science experiments over an extended period of time. The common cabin air assembly (CCAA) is utilized as the hardware for air temperature and humidity control (THC) for the CAM module cabin. The CCAA unit contains a variable speed fan, heat exchanger, temperature control valve, water separator, temperature sensor, and electrical interface box. A temperature and humidity simulation model was developed to perform the THC analysis for the CCAA unit inside the CAM. This model applies both fixed control volume and a quasi-steady-state approach for computing critical information for evaluating/assessing CCAA system performance and capabilities.

A consortium of interested parties has conducted an experimental characterization of two Tau parallel kinematic machines which were built as a part of the EU-funded project, SMErobot1. Characteristics such as machine stiffness, work envelope, repeatability and accuracy were considered. This paper will present a brief history of the Tau parallel machine, the results of this testing and some comment on prospective application to the aerospace industry.

Computational Fluid Dynamics airflow models for the Waste and Hygiene Compartment (WHC) in the U.S. Laboratory module and Node 3 were developed and examined. The International Space Station (ISS) currently provides human waste collection and hygiene facilities in the Russian Segment Service Module (SM) which supports a three person crew. An additional set of Russian hardware, known as the system, is planned for the United States Operational Segment (USOS) to support expansion of the crew to six persons. Integration of the Russian system into the USOS incorporates direct Environmental Control and Life Support System (ECLSS) interfaces to allow more autonomous operation. A preliminary design concept was used to create a geometry model to evaluate the air interaction with the module cabin at varied locations and performance of the avionics fan placed in WHC. The Russian and the privacy protection bump-outs (Kabin) were included into the present modeling.

Ventilation characteristics of the Columbus module are numerically predicted on the basis of the Reynolds-Averaged Navier-Stokes (RANS) and Large Eddy Simulation (LES) approaches. Effects of air supply diffuser modeling on computed flow are analyzed. An “effective diffuser” model that considerably reduces the number of computational cells for Columbus CFD ventilation analysis is proposed and tested. The computational models are verified by a comparison with the experimental data available. Special attention is paid to distinctions in fields of the time-averaged absolute velocity magnitude and the whole mean velocity that are due to the contribution of large-scale fluctuations. A technique to evaluate spatial distribution of the time-averaged absolute velocity magnitude using data of RANS steady-state predictions is suggested.

Orbital hole drilling technology has shown a great deal of promise for cost savings on applications in the aerospace industry where burr free, high quality holes are a necessity. This presentation will show some of the basic research on orbital drilling development Boeing is doing with the Advanced Manufacturing Research Center at Sheffield University and the deployment of the technology into production programs within The Boeing Company.

The Boeing Company has recently developed a portable positioning system based upon its patented flexible vacuum track technology, in support of its commitment to lean manufacturing techniques. The positioning system, referred to as Mini Flex Track, was initially developed as an inexpensive drilling system that minimizes machine setup time, does not require extensive operator training due to its simple user interface, is general purpose enough to be used in varying airplane applications, and meets strict accuracy requirements for aircraft manufacturing. The system consists of a variable length vacuum track that conforms to a range of contours, a two-axis numerically-controlled positioning carriage that controls machine motion, an additional rail perpendicular to the vacuum rail that provides transverse motion, and an end effector that can perform various tasks.

This paper will describe the Efficient Assembly Integration and Test (EAIT) system level project operated as a partnership among Boeing business units, universities, and suppliers. The focus is on the successful implementation and sharing of technology solutions to develop a model based, multi-product pulsed line factory of the future. The EAIT philosophy presented in this paper focuses on a collaborative environment that is tightly woven with the Lean Initiatives at Boeing's satellite development center. The prototype is comprised of a platform that includes a wireless instrumentation system, rapid bonding materials and virtual test of guidance hardware there are examples of collaborative development in collaboration with suppliers. Wireless tools and information systems are also being developed across the Boeing Company. Virtual reality development will include university partners in the US and India.

Jet fighter missions have been known to last extended period of time. The need for a comfortable and safe seat has become paramount considering that fact that uncomfortable seats can lead to numerous health issues. Several health effects like numbness, pressure sore, low back pain, and vein thrombosis have been associated with protracted sitting. The cushion, and of late the installation rail angle are the only components of the ejection seat system that can be modified to reduce these adverse effects. A comprehensive static comfort evaluation study for ejection seats was conducted. It provides comparison between a variety of operational and prototype cushions (baseline cushion, honeycomb and air-cushion) and three different installation rail angles (14°, 18°, and 22°). Three operational cockpit environment mockups with adjustable installation rail angle were built. Ten volunteer subjects, six females and four males, ages 19 to 35, participated in the seat comfort evaluation.

This paper presents a PC based mathematical and rapid prototyping technique for anthropometric accommodation in a maintenance environment using the principle of simulation based design. The developed technique is capable of analyzing anthropometric data using multivariate (Principal component Analysis) approach to describe the body size variability of any given population. A number of body size representative cases are established which, when used properly within the constraints of the maintenance environments, will ensure the accommodation of a desired percentage of a population. This technique evaluates the percentage accommodation of a given population for the environment using the specific manikin cases as boundary conditions. In the case where any member of a maintenance crew cannot be accommodated, the technique has the capability of informing the designer of the environment why the member(s) is/are not accommodated.

To serve the requirements of the operational environment of modern jet aircraft, the flight crew training program should be kept as simple as possible and be consistent with the total information system for aircraft operation of which it is a part. Systematic tools are described which assist the course developer in optimizing the implementation of Specific Behavioral Objectives, allocating learning elements to the most cost effective learning environment, and organizing those learning elements associated with the classroom environment. Included is a discussion on the management systems applied, the development of a Learning Task Analysis, and a systems approach to course organization.

Three distinct food system paradigms have been envisioned for long-term space missions. The Skylab, Mir and ISS food systems were based on single-serving prepackaged foods, ready to rehydrate and heat. Bioregenerative food systems, derived from crops grown and processed at the planetary station, have been studied at JSC and KSC. The US Antarctic Program’s Amundsen-Scott South Pole Base uses the third paradigm: bulk packaged food ingredients delivered once a year and used to prepare meals on the station. The packaged food ingredients are supplemented with limited amounts of fresh foods received occasionally during the Antarctic summer, trace amounts of herb and salad crops from the hydroponic garden, and some prepackaged ready to eat foods, so the Pole system is actually a hybrid system; however, it is worth studying as a bulk packaged food system because of the preponderance of bulk packaged food ingredients used.

There have been 17 fuel tank ignition events on commercial airplanes since 1959 that have resulted in 542 fatalities and 11 airplane losses. On the military side there have been 12 airplane losses on military version of the B-707 and the B-52 airplanes. The Most notable accident was the TWA 800 in July 1996 on the Boeing 747 which caused loss of 230 lives. This paper looks at the potential root causes of fuel tank explosions and the corrective actions that industry can undertake to minimize the hazard of fuel tank explosions. Fuel tank flammability and ignition sources are considered. The areas looked at are design, installation, and maintenance. Compliance to Federal Airworthiness Regulation are reviewed.

A fundamental part of airplane manufacturing involves hand drilling of holes for fasteners (bolts and rivets). The integrity of a fastener depends on the quality of its hole, which must be properly positioned, have a circular diameter of correct dimension, and be free of surface flaws and contaminants. A common method of drilling training is for a student to drill holes under the supervision of an instructor who inspects or measures the holes and makes suggestions for improving technique. This training method has proven to be effective, but it is time-consuming and requires considerable personal attention. We have devised instrumentation to monitor critical parameters (drill orientation and forces) so that a student can receive instantaneous visual feedback. This real-time feedback provides the student a better understanding of the drilling process and allows him or her to quickly make improvements.

The Human Swept Volume (HSV) software described here is an interactive tool that allows users to position and animate articulated human models and then generate tessellated swept volume solids. Inverse kinematics and keyframe interpolation are used to define motion sequences, and a voxel-based method is used to create swept volume solid models. The software has been designed to accept various human anthropometry models, which can be imported from other CAD tools. For our initial implementation, we defined several human models based on dimensions from CAESAR/SAE anthropometric data. A case study is described in which the swept volume software was used as a part of a human space occupancy analysis. Results show the advantages of using complete swept volumes for objective measurement comparisons.

The proliferation and growth of microorganisms in the Internal Active Thermal Control System (IATCS) aboard the International Space Station (ISS) has been of significant concern since 2001. Initial testing and assessments of biocides to determine bacterial disinfection capability, material compatibility, stability (rate of oxidative degradation and identification of degradation products), solubility, application methodology, impact on coolant toxicity hazard level, and impact on environmental control and life support systems identified a prioritized list of acceptable biocidal agents including glutaraldehyde, ortho-phthalaldehyde (OPA), and methyl isothiazolone. Glutaraldehyde at greater than 25 ppm was eliminated due to NASA concerns with safety and toxicity and methyl isothiazolone was eliminated from further consideration due to ineffectiveness against biofilms and toxicity at higher concentrations.