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The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.

An integration study was performed coupling an SP-100 reactor with either a Brayton or Stirling power conversion subsystem. A power level of 100 kWe was selected for the study. The power system was to be compatible with both the lunar and Mars surface environment and require no site preparation. In addition, the reactor was to have integral shielding and be completely self-contained, including its own auxiliary power for start-up. Initial reliability studies were performed to determine power conversion redundancy and engine module size. Previous studies were used to select the power conversion optimum operating conditions (ratio of hot-side temperature to cold-side temperature). Results of the study indicated that either the Brayton or Stirling power conversion subsystems could be integrated with the SP-100 reactor for either a lunar or Mars surface power application.

This SAE Aerospace Information Report (AIR) describes procedures for use in the field to determine if 115/200 Volt, 400 Hz aircraft external electrical power connectors are excessively worn, which may result in the inability of the external power plug to be retained, intermittent electrical performance and arcing.

This SAE Aerospace Information Report (AIR) describes procedures for use in the field to determine if 115/200 Volt, 400 Hz aircraft external electrical power connectors are excessively worn, which may result in the inability of the external power plug to be retained, intermittent electrical performance and arcing.

Governmental assurance documentation bibliography updated; new tabulation effective as of April 1, 1967. Latest revision indicated in all instances, but no attempt was made to list supplements or amendments. Department of Defense Index of Specifications and Standards (DODISS) published annually in three parts (alphabetic, numerical, and listing of Federal Supply Classification following unclassified documents.

Sundstrand has been investigating 270-Vdc/hybrid 115-Vac electrical power generating systems (EPGS) technology in preparation for meeting the electrical power generating system (EPGS) requirements for future aircraft (1). Systems such as the one being investigated are likely to be suitable for the More-Electric Aircraft (MEA) concepts presently under industry and military study. The present Sundstrand single-channel testbed is being further expanded to better understand the electrical system performance characteristics and power quality requirements of an MEA in which traditional mechanical subsystems are replaced by those of a “more-electric” nature. This paper presents the most recent Sundstrand 270-Vdc system transient performance data, and describes the modifications being made to the 270-Vdc/hybrid 115-Vac testbed.

Accurate measurement of countersinks in curved parts has always been a challenge. The countersink reference is defined relative to the panel surface which includes some degree of curvature. This curvature thus makes accurate measurements very difficult using both contact and 2D non-contact measurements. By utilizing structured light 3D vision technologies, the ability to very accurately measure a countersink to small tolerances can be achieved. By knowing the pose of the camera and projector, triangulation can be used to calculate the distance to thousands of points on the panel and countersink surface. The plane of the panel is then calculated using Random Sample Consensus (RANSAC) method from the dataset of points which can be adjusted to account for panel curvatures. The countersink is then found using a similar RANSAC method.

The need to improve quality while reducing cost in aerospace manufacturing is requiring new manufacturing methods and processes. Advanced technologies, such as 3D Image Metrology, offer great potential to lean manufacturing, if properly integrated into the production process. Over the last years 3D Image Metrology has developed a level of performance, which make it ideally suited for this purpose. These capabilities include the automatic in-process inspection of tools and parts before machining, machine control for highly accurate positioning during the machining operation, and in-process inspection during machining. This offers jig-less assembly, lower inventory, faster part throughput, and many more advantages.

This SAE Aerospace Information Report (AIR) describes field-level procedures to determine if 400 Hz electrical connections for external power may have been subjected to excessive wear, which may result in inadequate disengagement forces.

This SAE Aerospace Information Report (AIR) describes field-level procedures to determine if 400 Hz electrical connections for external power may have been subjected to excessive wear, which may result in inadequate disengagement forces.

This SAE Recommended Practice which defines the terms and tabulates the limits of the characteristics for various protective devices used in conjunction with 400-cycle ground power for civil aircraft is intended to assist the airlines in standardizing on 400-cycle protective systems. The limits found to be acceptable in the civil aircraft industry are presented.

Flex Track Systems are seeing increased usage in aerospace applications for joining large assemblies, such as fuselage sections. Previous systems were limited to work pieces that allowed the tracks to follow a gentle radius of curvature, limiting the locations where the system could be used. This paper describes a new 5-Axis Flex Track System developed to expand the usage of the systems, allowing them to process work pieces containing complex and irregular contours. Processing complex contours is accomplished through the addition of A and B axes providing normalization in multiple directions. These new systems are configured with the latest multi-function process capabilities allowing drilling, hole quality measurement, and temporary or permanent fastener installation.

The Automated Spar Assembly Tool (ASAT II) at the Everett, Washington, 777 Boeing manufacturing facility could be the largest automated fastening cell in the commercial aircraft industry. Based on the success of the ASAT I, Boeing's 767 spar assembly tool, the 285-foot long ASAT II cell was needed to accurately position and fasten the major spar components (chords and web), then locate and fasten over 100 components (ribposts and stiffeners) to assemble the 777 forward and rear wing spars. From its inception in 1990 to the first drilled hole in January 1993 and through two years of spar production, the more advanced ASAT II has proven to be a greater success than even its 767 ASAT I predecessor. This massive automated fastening system consistently provides accurate hole preparation, inspection, and installation of three fastener types ranging from 3/16 inches to 7/16 inches in diameter.

Wing panels for Boeing's new 777 airplane are assembled using fastening machines called Wing Fastener Systems (WFS). Compared to the wing riveting machines currently used to squeeze rivets for other airplane models, the 777 WFS provides significantly more features in that it also installs two part fasteners, collects process data for Statistical Process Control analysis, plus other functions. Historically, new operators for wing riveting machines have needed six months of on-the-job training to achieve basic qualification. Because of the increased functionality of the 777 WFS, an eight to nine month O.J.T. requirement was anticipated. Training requirements were further compounded by our need for up to thirty qualified operators in a relatively short time frame and a maintenance staff thoroughly trained in the new control architecture. Boeing's response to this challenge was to use simulation methods similar to those used to train pilots for our customer airlines.

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.

Flight control technology for 8000 psi has emerged almost simultaneously with new fire-resistant hydraulic fluids, such as MIL-H-83282 and CTFE. A proliferation of industry recommendations has resulted in a wide variety of mechanisms for solving associated actuator design problems, including tighter clearances, special seals, finishes, materials, and many others. As there are few common agreements on the issues, an extensive three-phase test program was undertaken to attempt to corroborate some of these approaches or suggest others that may be better or more cost effective.

An 8000 psi test program was conducted to resolve conflicts and issues surrounding the use of CTFE and MIL-H-83282 fluid with vented and unvented actuator rod seals. Each of the four possible combinations had unique problems and each responded to appropriate corrections including new backup rings designed to operate with standard clearances. It was concluded that all combinations were viable within certain limits. Advantages and disadvantages of each configuration were identified and specific recommendations made for both dynamic and static seals within the context of existing military specifications.

Shortly after World War II, as aircraft became more sophisticated and power-assist, flight-control functions became a requirement, hydraulic system operating pressures rose from the 1000 psi level to the 3000 psi level found on most aircraft today. Since then, 4000 psi systems have been developed for the U.S. Air Force XB-70 and B-1 bombers and a number of European aircraft including the tornado multirole combat aircraft and the Concorde supersonic transport. The V-22 Osprey incorporates a 5000 psi hydraulic system. The power levels of military aircraft hydraulic systems have continued to rise. This is primarily due to higher aerodynamic loading, combined with the increased hydraulic functions and operations of each new aircraft. At the same time, aircraft structures and wings have been getting smaller and thinner as mission requirements expand. Thus, internal physical space available for plumbing and components continues to decrease.

Shortly after World War II, as aircraft became more sophisticated and power-assist, flight-control functions became a requirement, hydraulic system operating pressures rose from the 1000 psi level to the 3000 psi level found on most aircraft today. Since then, 4000 psi systems have been developed for the U.S. Air Force XB-70 and B-1 bombers and a number of European aircraft including the tornado multirole combat aircraft and the Concorde supersonic transport. The V-22 Osprey incorporates a 5000 psi hydraulic system. The power levels of military aircraft hydraulic systems have continued to rise. This is primarily due to higher aerodynamic loading, combined with the increased hydraulic functions and operations of each new aircraft. At the same time, aircraft structures and wings have been getting smaller and thinner as mission requirements expand. Thus, internal physical space available for plumbing and components continues to decrease.

A baseline design has been selected for the Space Station Habitat (HAB) element. The HAB provides the primary living space to support man's permanent presence in space. The HAB element is designed to provide an environment that maximizes safety and human productivity. This paper outlines some of the current design features including the common core elements and the man-systems hardware. The HAB is arranged in three areas based on crew activity and acoustical considerations. The first area is the quiet zone, which contains the crew quarters. The second area is a buffer zone for noise suppression, where the stowage, medical facilities, and personal hygiene facilities are located. The third area is the active zone which contains the galley/wardroom, laundry and exercise facilities. Each of these three areas will be discussed together with the applicable requirements, the common utility elements, and the man-systems hardware furnishings.