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After launch and activation activities, the Columbus module started its operational life on February 2008 providing resources to the internal and external experiments. In March 2008 two US Payloads were successfully installed into Columbus Module: Microgravity Sciences Glovebox (MSG) and a US payload of the Express rack family, Express Rack 3, carrying the European Modular Cultivation System (EMCS) experiment. They were delivered to the European laboratory from the US laboratory and followed few months later by similar racks; Human Research Facility 1 (HRF1) and HRF2. The following paper provides an overview of US Payloads, giving their main features and experiments run inside Columbus on year 2008. Flight issues, mainly on the hydraulic side are also discussed. Engineering evaluations released to the flight control team, telemetry data, and relevant mathematical models predictions are described providing a background material for the adopted work-around solutions.

The objective of this study is to evaluate ventilation efficiency regarding to the International Space Station (ISS) cabin ventilation during the ISS assembly mission 1J. The focus is on carbon dioxide spatial/temporal variations within the Node 2 and attached modules. An integrated model for CO2 transport analysis that combines 3D CFD modeling with the lumped parameter approach has been implemented. CO2 scrubbing from the air by means of two ISS removal systems is taken into account. It has been established that the ventilation scheme with an ISS Node 2 bypass duct reduces short-circuiting effects and provides less CO2 gradients when the Space Shuttle Orbiter is docked to the ISS. This configuration results in reduced CO2 level within the ISS cabin.

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.

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.

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.

Estimates of the effectiveness of the high-hydrogen containing materials, sodium alanate and ammonia borane, are made by calculating dose and dose equivalent for the 1977 solar minimum and 1970 solar maximum galactic cosmic ray spectra and for the large solar particle event spectra from the space era event of August 1972 and comparing their shielding effectiveness with that of polyethylene.

Solar proton events (SPEs) represent the single-most significant source of acute radiation exposure during space missions. Historically, an exponential in rigidity (particle momentum) fit has been used to express the SPE energy spectrum using GOES data up to 100 MeV. More recently, researchers have found that a Weibull fit better represents the energy spectrum up to 1000 MeV (1 GeV). In addition, the availability of SPE data extending up to several GeV has been incorporated in analyses to obtain a more complete and accurate energy spectrum representation. In this paper we discuss the major SPEs that have occurred over the past five solar cycles (~50+ years) in detail - in particular, Aug 1972 and Sept & Oct 1989 SPEs. Using a high-energy particle transport/dose code, radiation exposure estimates are presented for various thicknesses of aluminum. The effects on humans and spacecraft systems are also discussed in detail.

Statistical Energy Analysis (SEA) is a very powerful tool in its ability to guide noise control package design in automobile, airplane and architectural systems. However transmission loss modeling in an SEA frame work has more to do with modeling of sound propagation through foam and fiber noise control materials than classical SEA power flow between groups of resonant modes. The transmission loss problem is reviewed in an SEA frame work with a focus on key paths and input parameter variations on predicted noise control package performance.

The modeling and simulation of electrical power systems has become a primary design tool for the synthesis of aerospace power systems with hybrid AC/DC distribution. Although in the past the use of extensive time domain simulations using detailed models has been favored, the need to study stability and associated phenomena in this type of power systems-having a high penetration of power electronics loads-has transformed the modeling requirements for aerospace applications. This paper explores different modeling aspects required to study both small-signal and large-signal stability in these systems, providing insight into the development of key system component models-variable frequency generators, line-commutated converters, PWM motor drives and constant power loads, as well as the theoretical foundations based on the Generalized Nyquist Criterion and the Lyapunov Direct and Indirect Methods to fully assess the stability conditions of these power systems.

A study was conducted to investigate the impacts of obstacles on pilot performance, workload, and perceptions of safety in a visual flight rule (VFR) obstacle-rich environment (ORE). The study was conducted using a piloted simulation of a single-rotor, multi-engine helicopter operating in a highly detailed urban visual scene database. The database contained multiple obstacle types, with variable obstacle heights and densities. Nine pilots completed the approaches and departures into and out of a heliport located in the center of the generic urban environment. Two flight routes offered unique presentations of terrain and obstacle types. Obstacle height/density and time of day/lighting parameters were systematically manipulated. A multi-dimensional data collection methodology employing the simultaneous collection of direct aircraft state, pilot performance data, pilot physiological data and pilot subjective responses was employed.

The Carbon Dioxide Removal Assembly (CDRA) is a part of the International Space Station (ISS) Environmental Control and Life Support (ECLS) system. The CDRA provides carbon dioxide (CO2) removal from the ISS on-orbit modules. Currently, the CDRA is the secondary removal system on the ISS, with the primary system being the Russian Vozdukh. Within the CDRA are two Desiccant/Adsorbent Beds (DAB), which perform the carbon dioxide removal function. The DAB adsorbent containment approach required improvements with respect to adsorbent containment. These improvements were implemented through a redesign program and have been implemented on units on the ground and returning from orbit. This paper presents a DAB design modification implementation description, a hardware performance comparison between the unmodified and modified DAB configurations, and a description of the modified DAB hardware implementation into the on-orbit CDRA.

Both humans and onboard radiosensitive systems (electronics, materials, payloads and experiments) are exposed to the deleterious effects of the harsh space radiations found in the space environment. The purpose of this paper is to present the space radiation environment extended to deep space based on environment models for the moon, Mars, Jupiter, and Saturn and compare these radiation environments with the earth's radiation environment, which is used as a comparative baseline. The space radiation environment consists of high-energy protons and electrons that are magnetically “trapped” in planetary bodies that have an intrinsic magnetic field; this is the case for earth, Jupiter, and Saturn (the moon and Mars do not have a magnetic field). For the earth this region is called the “Van Allen belts,” and models of both the trapped protons (AP-8 model) and electrons (AE-8 model) have been developed.

Protecting astronauts from space radiation exposure is an important challenge for mission design and operations for future exploration-class and long-duration missions. Crew members are exposed to sporadic solar particle events (SPEs) as well as to the continuous galactic cosmic radiation (GCR). If sufficient protection is not provided the radiation risk to crew members from SPEs could be significant. To improve exposure risk estimates and radiation protection from SPEs, detailed evaluations of radiation shielding properties are required. A model using a modern CAD tool ProE™, which is the leading engineering design platform at NASA, has been developed for this purpose. For the calculation of radiation exposure at a specific site, the cosine distribution was implemented to replicate the omnidirectional characteristic of the 4π particle flux on a surface.

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).

A procedure for calculating the engine inlet diffuser section liquid water content and mass fractions of liquid water content associated with the water droplet size distribution for wind milling engine ice accretion analysis is presented. Critical fuel reserve calculation for extended twin-engine operation requires the determination of drag increase due to ice accretion on inoperative wind milling engine fan blade and guide vane.

The robust stability of an active flexible wing section with leading- and trailing-edge control surfaces is further investigated via the μ-method. Motivated by a more detailed servo control dynamics, the two controllers K1 and K2, which command the deflections of the trailing-edge flap and the leading-edge flap respectively, are modeled as two second-order shock absorbers in this study. The nominal and robust stability margins, modal properties, critical flutter airspeeds and frequencies are computed to predict the flutter of a nonlinear aeroelastic system and to investigate the aeroservoelastic stability in the μ-framework. The simulation results are compared with the previous study of which the controllers were modeled as the simplified (first-order) shock absorbers. The improved sensitivity to detect the control-structure coupling is observed by applying the second-order shock absorbers in the ASE model.

There is an increasing demand in the aerospace industry for automated machinery that is portable, flexible and light. This paper will focus on a joint project between BROETJE-Automation and Boeing called the Universal Splice Machine (USM). The USM is a portable, flexible and lightweight automated drilling and fastening machine for longitudinal splices. The USM is the first machine of its kind that has the ability not only to drill holes without the need to deburr, (burrless drilling) but also to insert fasteners. The Multi Function End Effector (MFEE) runs on a rail system that is mounted directly on the fuselage using a vacuum cup system. Clamp up is achieved through the use of an advanced electromagnet. A control cart follows along next to the fuselage and includes an Automated Fastener Feeding System. This paper will show how this new advancement has the capabilities to fill gaps in aircraft production that automation has never reached before.

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.

Dimensional Management (DM) is a methodology to predict and control the impact of variation on assembly from, fit, and function. Application of Dimensional Management tools and other modeling and simulation techniques are combined in a process called 3D Re-Engineering for application to existing production designs. Analytical techniques for predicting the impact of variation on assembly fit, and corresponding methods for controlling variation are presented, as used in a production environment for root cause corrective action on existing assembly fit problems. Assembly variation analysis is typically performed early in the product development phases, by coordinating datums, assembly sequences, assembly methods, and detail part tolerances across the product development team.

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.