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The C-17 airplane operates in some of the most challenging environments in the world including semi prepared runway operations (SPRO). Typical semi-prepared runways are composed of a compacted soil aggregate of sand, silt, gravel, and rocks. When the airplane lands or takes off from a semi-prepared runway, debris, including sand, gravel, rocks and, mud is kicked up from the nose landing gear (NLG) and the main landing gear (MLG) tires. As the airplane accelerates to takeoff or decelerates from landing touchdown, this airborne debris impacts the underbelly and any component mounted on the underbelly. The result is the erosion of the protective surface coating and damage to systems that protrude below the fuselage into the debris path. The financial burden caused by SPRO damage is significant due to maintenance costs, spares costs and Non-Mission Capable (NMC) time.

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.

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.

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.

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 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.

This study was designed to answer what percent of “required” traffic pilots acquire visually using the current “visual acquisition system” of windows, eyes and the Traffic Collision Avoidance System (TCAS). “Required Traffic” was defined as Air Traffic Control (ATC) calls to the research aircraft, TCAS Traffic Alerts and/or TCAS Resolution Advisories. The results of the approximately 40 hours of flight were that the majority of (“required”) traffic was NOT visually acquired (39% visually acquired; 61% not visually acquired). When traffic was identified to the pilots by more than one source, the visual acquisition rate was 58%. For validation purposes, an additional 10 hours of flight observations were made during revenue flights with a major airline. Flight test and airline observations were found to be comparable.

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.

The patented (US 7,277,811 B1) Position Bar provides precise measurement, machining and drilling data for large Engineering and Tooling structure. The Position Bar also supports end item verification seamlessly in the same machining control code. Position Bar measurements are fast, accurate, and repeatable. The true centerline of the machine tool's spindle bearings are being measured to within .002 in a 20 foot cubic volume (20×20×20). True “I”, “J”, & “K” machine tool spindle positions are also precisely measured. Any Gantry or Post Mill Tool can be converted to a Coordinate Measurement Machine (CMM) with this laser tracker controlled Position Bar. Determinant Assembly (D.A.) holes, for fuselage and wing structures are drilled and then measured to within .006 in X, Y, & Z, over a 40 foot distance. Average laser tracker measurement time, per hole, is 2 seconds.

NASA has long recognized the advantages of providing improved information interfaces to EVA astronauts and has pursued this goal through a number of development programs over the past decade. None of these activities or parallel efforts in industry and academia has so far resulted in the development of an operational system to replace or augment the current extravehicular mobility unit (EMU) Display and Controls Module (DCM) display and cuff checklist. Recent advances in display, communications, and information processing technologies offer exciting new opportunities for EVA information interfaces that can better serve the needs of a variety of NASA missions. Hamilton Sundstrand Space Systems International (HSSSI) has been collaborating with Simon Fraser University and others on the NASA Haughton Mars Project and with researchers at the Massachusetts Institute of Technology (MIT), Boeing, and Symbol Technologies in investigating these possibilities.

Trace chemical contaminants produced by equipment offgassing and human metabolic processes are removed from the atmosphere of the International Space Station's U.S. Segment by a trace contaminant control subassembly (TCCS). The TCCS employs a combination of physical adsorption, thermal catalytic oxidation, and chemical adsorption processes to accomplish its task. A large bed of granular activated charcoal is a primary component of the TCCS. The charcoal contained in this bed, known as the charcoal bed assembly (CBA), is expendable and must be replaced periodically. Pre-flight engineering analyses based upon TCCS performance testing results established a service life estimate of 1 year. After nearly 1 year of cumulative in-flight operations, the first CBA was returned for refurbishment. Charcoal samples were collected and analyzed for loading to determine the best estimate for the CBA's service life.

The OVERFLOW chimera grid Navier Stokes code was used to analyze a wide variety of airplane configurations. The code performed reliably and was found to have comparable accuracy to the structured grid code TLNS3D. It is easier to develop overlapping grid blocks to represent a complex configuration than it is to develop grid blocks that must abut one another. The process is inherently modular. One can add or subtract components like tip-lights, compound winglets, struts, nacelles, tails and fairings at will. The gain in grid simplicity is offset by the complication in specifying block connectivity, however. The overset blocks are typically of better quality, but there is a drawback in that it is not always possible to guarantee flux conservation. The recent development of software for automatic connectivity holds promise for the routine use of OVERFLOW by design engineers.

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.

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system includes regenerative and non-regenerative technologies that provide the basic life support functions to support the crew, while maintaining a safe and habitable shirtsleeve environment. This paper provides a summary of the U.S. ECLS system activities over the past year, covering the period of time between May 2001 and April 2002. The ISS continued permanent crew operations, with Phase 2 completion accomplished during this period. Work continued on the Phase 3 elements with Node 3 proceeding toward a final design review and the regenerative ECLS equipment proceeding into manufacturing.

Clothing supply has been examined for historical, current, and planned missions. For STS, crew clothing is stowed on the orbiter and returned to JSC for refurbishment. On Mir, clothing was supplied and then disposed of on Progress for incineration on re-entry. For ISS, the Russian laundry and 75% of the US laundry is placed on Progress for destructive re-entry. The rest of the US laundry is stowed in mesh bags and returned to earth in the Multi Purpose Logistics Module (MPLM) or in the STS middeck. For previous missions, clothing was supplied and thrown away. Supplying clothing without washing dirty clothing will be costly for long-duration missions. An on-board laundry system may reduce overall mission costs, as shown in previous, less accurate, metric studies. Some design and development of flight hardware laundry systems has been completed, such as the SBIR Phase I and Phase II study performed by UMPQUA Research Company for JSC in 1993.

Out-of-round holes are formed as a result of tool motion during drilling. Tool vibration is driven by radial and tangential forces on the primary and secondary cutting edges. These forces in turn depend on the chip loads on each cutting edge, which in turn depend on the position of the tool at the current time and at the time of the previous tooth passage. A preliminary analysis based on balancing the cutting forces and the bending forces on the tool, shows that the characteristic frequencies of motion of the tool in the tool frame are near 3/rev, 5/rev, 7/rev etc. (corresponding to 2/rev, 4/rev, 6/rev) in the workpiece frame. These motions are consistent with the tool motion and hole form errors commonly observed on the shop floor. We will describe procedures for measuring the dependence of cutting forces on chip load, the development of simple equations for lateral motion of the tool, and solutions for the tool's behavior.

Decades ago our innovative grandfathers developed the first automated riveting machines based on hard automation using kinematics and tools attached to a C-frame. The C-frame serves multiple functions: First, it holds the upper and lower tools in fixed positions relative to each other; second, it translates upper active tooling forces to the lower tool; and third, it embraces the part placed between the upper and lower tool. C-frames and newly developed yoke, ring and gantry machines, used for low level (first, second) fuselage and wing assembly are growing in size to exorbitant proportions to satisfy requirements of larger and larger structures. High costs are dictated by massive kinematics and complex controls that provide stability, precision, and process speed. All this is mainly needed because we have to carry mechanical forces around the part, from upper to lower tool along the C-frame, gantry, yoke, bridge, etc.

Fabrication and assembly of the majority of control surfaces for Boeing’s 777X airplane is completed at the Boeing Defense, Space and Security (BDS) site in St. Louis, Missouri. The former 777 airplane has been revamped to compete with affordability goals and contentious markets requiring cost-effective production technologies with high maturity and reliability. With tens of thousands of fasteners per shipset, the tasks of drilling, countersinking, hole inspection, and temporary fastener installation are automated. Additionally and wherever possible, blueprint fasteners are automatically installed. Initial production is supported by four (4) Electroimpact robotic systems embedded into a pulse-line production system requiring strategic processing and safeguarding solutions to manage several key layout, build and product flow constraints.