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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.

International Space Station (ISS) Payload Engineering Integration (PEI) organization adopted the advanced computation and simulation technology to develop integrated electrical system models based on the test data of various sub-units. This system model was used end-to-end to mitigate system risk for the integrated Space Shuttle Pre-launch and Landing configurations. The Space Shuttle carries the Multi-Purpose Logistics Module (MPLM), a pressurize transportation carrier, and the Laboratory Freezer for ISS, a freezer rack for storage and transport of science experiments from/to the ISS, is carried inside the MPLM. An end-to-end electrical system model for Space Shuttle Pre-Launch and Landing configurations, including the MPLM and Freezer, provided vital information for integrated electrical testing and to assess Mission success. The Pre-Launch and Landing configurations have different power supplies and cables to provide the power for the MPLM and the Freezer.

The new materials and material combinations such as composites and titanium combinations used on today's new airplanes are proving to be very challenging when drilling holes during manufacturing and assembly operations. Orbital hole drilling technology has shown a great deal of promise for generating burr free, high quality holes in hard metals and in composite materials. This paper will show some of the orbital drilling development work Boeing is doing with Novator to overcome the obstacles of drilling holes in a combination of both hard metals and composites. The paper will include a new portable orbital drilling system designed for these challenging applications as well as some test results achieved with this system.

Currently scheduled to be delivered to the International Space Station (ISS) in 2009, Crew Quarters (CQs) will be installed in the Node 2 Module. The CQs provide crewmembers with private space, a place to sleep, and minimal storage. Analysis is to be performed to determine if the United States Operational Segment (USOS) Node 2 can maintain temperature between 47°C and 62°C (65°F and 80°F) [units are CCGS with U.S unit in parenthesis] within the CQ. The analysis will concentrate on the nominal hot environmental case. Environmental heat is due to solar heating of the external shell of the ISS. Configurations including both three and four CQs are examined, as well as multiple configurations of the Low Temperature Loop (LTL) that flows through the Node 2 Common Cabin Air Assembly (CCAA). This paper describes the analysis performed to determine if Node 2 will be able to maintain cabin temperature between 47°C and 62°C (65°F and 85°F).

The development of new commercial airliners is a very risky proposition. To get it right, airframe manufacturers must balance new technologies and manufacturing methods with global participation and business considerations. The 787 is Boeing's popular new wide body aircraft incorporating state of the art composites design and manufacturing methods. But new technology alone is not enough. A new logistics system was needed to integrate global partners in order to fully benefit from new technologies. The Boeing 747-400 Dreamlifter is a special purpose 747-400 modified to transport Boeing 787 airplane components through various stages of manufacturing.

In recent years there has been increasing interest in quantifying the emissions from aircraft in order to generate inventories of emissions for climate models, technology and scenario studies, and inventories of emissions for airline fleets typically presented in environmental reports. The preferred method for calculating aircraft engine emissions of NOx, HC, and CO is the proprietary “P3T3” method. This method relies on proprietary airplane and engine performance models along with proprietary engine emissions characterizations. In response and in order to provide a transparent method for calculating aircraft engine emissions non proprietary fuel flow based methods 1,2,3 have been developed. This paper presents derivation, updates, and clarifications of the fuel flow method methodology known as “Fuel Flow Method 2”.

This white paper will outline the material and processes, which have been developed for the fabrication and application of an integrated composite firewall primary structure for use in military and commercial aircraft. Military and commercial aircraft have requirements to protect occupants from fire. One specific fire protection requirement is to contain a (1100°C/2000°F) flame for 15 minutes. This protection on composites is usually provided by a metallic firewall attached to the composite structure. The integrated ceramic composite firewall is an improvement over existing metallic firewall technology. This technology reduces cost, part count, weight, and manufacturing complexity of composites, which require fire protection. The integrated ceramic composite firewall material and process incorporates ceramic fabric and film adhesive into one unique material.

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.

Fastening metallic structure for aerospace applications is relatively straightforward and has been done for some time. Dealing with advanced composites, though, requires a significantly different technological approach, especially primary structure. Although composite material utilization has increased enormously in civil and military aircraft in recent years, the application of composite materials to primary aircraft structure has not kept pace and is still greeted with some skepticism in the aerospace community. In particular, no major transport manufacturer has yet employed composite components for fuselage or wing primary structure. This appears to be changing rather rapidly with the introduction and the evolution of new airframes such as the 7E7 and Blended Wing Body (BWB) concepts.

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.

Use of graphite/resin composites in engine nacelles has been restricted because the resin is flammable. Fiberglass/polyimide and graphite/polyimide laminates were treated with various phosphorylated polymers to obtain enhanced fire-resistance and high-char-yield products after exposure to a 2000°F flame for 15 minutes. Tensile, flexural shear, and interlaminar shear strengths were determined. Polymeric phosphorylated hydrazides were found to give the best fire-resistance.

Metal cutting is a substantial constituent of airframe manufacturing. During the past several decades, it has evolved significantly. However, most of the changes and improvement were initiated by the machine tool industry and cutting tool industry, thus these new technologies is generally applicable to all industries. Among them, few are developed especially for the airframe manufacture. Therefore, the potential of high efficiency could not be fully explored. In order to deal with severe competition, the aerospace industry needs improvement with a focus on achieving low cost through high efficiency. The direction of research and development in parts machining must comply with lean manufacturing principles and must enhance competitiveness. This article is being forwarded to discuss the trend of new developments in the metal cutting of airframe parts. Primary driving forces of this movement, such as managers, scientists, and engineers, have provided significant influence to this trend.

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.

Crewmember ingress of the International Space Station (ISS) before that time accorded by the original ISS assembly sequence, and thus before the ISS capability to adequately control the levels of temperature, humidity, and carbon dioxide, poses significant impacts to ISS Environmental Control and Life Support (ECLS). Among the most significant considerations necessitated by early ingress are those associated with the capability of the Shuttle Transportation System (STS) Orbiter to control the aforementioned levels, the capability of the ISS to deliver the conditioned air among the ISS elements, and the definition and distribution of crewmember metabolic heat, carbon dioxide, and water vapor. Even under the assumption that all Orbiter and ISS elements would be operating as designed, condensation control and crewmember comfort were paramount issues preceding each of the ISS Missions 2A and 2A.1.

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.

The temperature and humidity of the air within the habitable areas of the International Space Station are controlled by a set of hardware and software collectively referred to as the Temperature and Humidity Control (THC) subassembly. This subassembly 1) controls the temperature of the cabin air based on a crew selected temperature, 2) maintains humidity within defined limits, and 3) generates a ventilation air flow which circulates through the cabin. This paper provides descriptions of the components of the THC subassembly, their performance ranges, and the control approach of the hardware. In addition, the solutions of the design challenges of maintaining a maximum case radiated noise level of NC 45, controlling the cabin air temperature to within ±2°F of a setpoint temperature, and providing a means of controlling microbial growth on the heat exchanger surfaces are described.

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.