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Environmental Control Systems (ECS) ducts on airplanes are primarily fabricated from aluminum or thermoset composites, depending on temperature and pressure requirements. It is imperative to fabricate lightweight, cost effective, durable, and repairable systems with minimal tooling. It is also important that the duct systems are easy to assemble even with alignment issues resulting from structural variations, tolerance accumulation, variation from thermal expansion of different materials, and inherent duct stiffness. These requirements create an opportunity and need for a technology that can address all of these issues, while increasing performance at the same time. This report provides a background on current ECS ducting systems.

The on-orbit oxygen and nitrogen supply for the United States On-Orbit Segment (USOS) of the International Space Station (ISS) is provided in tanks mounted on the outside of the Airlock module. Gasses are supplied, for distribution to users within the USOS, via pressure regulators in the Airlock. The on-orbit storage can be replenished with gas that is scavenged from the Space Shuttle, or by direct replacement of the tanks. The supply and distribution system are described in this paper. The users of the gasses are identified. The system architecture is presented. Operational considerations are discussed.

Excessive impact pressures can develop when an evacuated system is filled with liquid. Such a process is usually highly chaotic, especially when the system geometry is complex. Available computational methods by themselves cannot provide the necessary answers. The International Space Station (ISS) heat exchanger has a complex flow system, and a synthesis of computational and experimental methods was necessary to design the system. The FLOW-NET two-phase flow program was used to determine the range of loss coefficients and the liquid-vapor interface mass and energy transfer that would fit the measured impact pressures. These loss coefficients could then be used to compute the impact pressures for a design configuration similar to the one tested at a range of operating conditions.

The International Space Station (ISS) requires stores of Oxygen (O2) and Nitrogen (N2) to provide for atmosphere replenishment, direct crew member usage, and payload operations. Currently, supplies of N2/O2 are maintained by transfer from the Space Shuttle. Following Space Shuttle retirement in 2010, an alternate means of resupplying N2/O2 to the ISS is needed. The National Aeronautics and Space Administration (NASA) has determined that the optimal method of supplying the ISS with O2/N2 is using tanks of high pressure N2/O2 carried to the station by a cargo vehicle capable of docking with the ISS. This paper will outline the architecture of the system selected by NASA and will discuss some of the design challenges associated with this use of high pressure oxygen and nitrogen storage in the human spaceflight environment.

The Portable Fastener Delivery System or PFDS, has been developed at the Boeing St. Louis facility to streamline the manual fastener installation process. The PFDS delivers various fasteners, on demand, through a delivery tube to an installation tool used by the operator to install the fasteners in an aircraft assembly. This paper describes the PFDS in its current configuration, along with the associated Huck® International (now Alcoa Fastening Systems) installation tooling, as it is being implemented on the F/A-18E/F Nosebarrel Skinning application. As a “portable” system, the PFDS cart can be rolled to any location on the shop floor it might be needed. The system uses a removable storage cassette to cache many sizes and types of fasteners in the moderate quantities that might be required for a particular assembly task. The operator begins the installation sequence by calling for the particular fastener grip length needed using a wireless control pendant.

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.

The Nitrogen System aboard the International Space Station (Station) continues to maintain Station total pressure and support several ongoing scientific and medical tasks. This paper addresses elevated leakage in the Nitrogen System, behavior during events such as nitrogen usage in other parts of the Station, and describes behavioral changes of the nitrogen Regulator/Relief Valve (regulator) since the activation of the Nitrogen System in 2001.

ESA and NASA agencies agreed to run an interface compatibility test at the EADS facility between the Columbus flight module and a duplicate ground unit of a currently on-orbit US International Standard Payload Rack, the Human Research Facility (HRF) Flight Prototype Rack (FPR). The purpose of the test was to demonstrate the capability to run US payloads inside the European ISS module Columbus. One of the critical aspects to be verified to ensure suitable operations of the two systems was the combined performance of the hydraulic controls resident in the HRF and Columbus coolant loops. A hydraulic model of the HRF FPR was developed and combined with the Columbus Active Thermal Control System (ATCS) model. Several coupled thermal-hydraulic test cases were then performed, preceded by mathematical analysis, required to predict safe test conditions and to optimize the Columbus valve configurations.

The International Space Station (ISS) loses cabin atmosphere mass at some rate. Due to oxygen partial pressures fluctuations from metabolic usage, the total pressure is not a good data source for tracking total pressure loss. Using the nitrogen partial pressure is a good data source to determine the total on-orbit cabin atmosphere loss from the ISS, due to no nitrogen addition or losses. There are several important reasons to know the daily average cabin air loss of the ISS including logistics planning for nitrogen and oxygen. The total average daily cabin atmosphere loss was estimated from January 14 to April 9 of 2003. The total average daily cabin atmosphere loss includes structural leakages, Vozdukh losses, Carbon Dioxide Removal Assembly (CDRA) losses, and other component losses.

Electromagnetic forming (EMF) technology has been used lately for the joining and assembly of axisymmetric parts in the aerospace and automotive industries. A few case studies of compressive-type joining processes applied on both aluminum and titanium or stainless tubes for aerospace applications are presented. In the first case study, tests were conducted using 2024-T3 drawn tubes joined with a steel end fitting to form a torque tube using different forming variables including: the fitting geometry, material formability and forming power (KJ). The power setting and the fitting geometry were optimized to improve the fatigue life, torque off, and the axial load capability of the torque tube joints to drive the leading and trailing edge high-lift devices.