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In the last several years, technical advances and regulatory pressures have motivated the need for flexible, simple, and performance-based solutions for conducting development assurance in support of a system safety assessment process. Additionally, the affected design space for commercial vehicles has been growing beyond the conventional regulations for airplanes, rotorcraft, engines, and propellers, addressed by current Aerospace Recommended Practices (ARPs). This space is beginning to include commercial technologies such as unmanned aerial systems, multi-stage spacecraft systems, and road-able aircraft. These developing areas are each accompanied with their own development assurance expectations in support of their safety criteria. Concurrently, the industry and regulators are working to simplify guidance for system safety and development assurance, which has been foundational in the aircraft industry for decades.

The Internal Thermal Control System (ITCS) has been developed jointly by Boeing Corporation, Huntsville, Alabama and Honeywell Engines & Systems, Torrance, California to meet the internal thermal control needs for the International Space Station (ISS). The ITCS provides heat removal for the critical life support systems and thermal conditioning for numerous experiment racks. The ITCS will be fitted on a number of modules on the ISS. The first US Element containing the ITCS, Node 1, was launched in December 1998. Since Node 1 does not contain a pump to circulate the fluid it was not filled with ITCS fluid until after the US Laboratory Module was installed. The second US Element module, US Laboratory Module, which contains the pumps and all the major ITCS control hardware, was launched in February 2001. The third US Element containing the ITCS, the US Airlock, was launched in July 2001.

In AFP manufacturing systems, manually inspection of parts consumes a large portion of total production time and is susceptible to missing defects. The aerospace industry is responding to this inefficiency by focusing on the development of automated inspection systems. The first generation of automated inspection systems is now entering production. This paper reviews the performance of the first generation system and discusses reasonable expectations. Estimates of automated inspection time will be made, and it will be shown that the automated solution enables a detailed statistical analysis of manufactured part quality and provides the data necessary for statistical process control. Data collection allows for a reduction in rework because not all errors need to be corrected. Expectations will be set for the accuracy for both ply boundary and overlap/gap measurements. The time and resource cost of development and integration will also be discussed.

Traditionally, vehicle power wiring safety has consisted of a reactive thermal circuit breaker that responds to an overload condition. In addition, maintenance operations have been reactive as well, searching for a possible damaged section of wiring in a large and often difficult to access wire bundle. Advancements in detection of changes in impedance, arc, corona, and reflectometry to measure general wire damage have the potential to automate the process, while increasing vehicle safety and reducing costs. Some of these technologies are also pro-active and can warn of a potential problem during routine maintenance checks using hand held instrumentation or if embedded in a vehicle can detect problems prior to power up or after system power up using real-time monitoring.

The design, development and testing of electric brakes for the DARPA/USAF/Boeing X-45A Unmanned Combat Air Vehicle (UCAV) demonstrator is discussed. The UCAV effort presented a new set of challenges and capability requirements for the brake system. A selection of electric brake technical development results is presented.

This set is comprised of two titles, Aircraft Thermal Management: Systems Architectures and Aircraft Thermal Management: Integrated Energy Systems Analysis both edited by Mark Ahlers.

Aircraft thermal management (ATM) is increasingly important to the design and operation of commercial and military aircraft due to rising heat loads from expanded electronic functionality, electric systems architectures, and the greater temperature sensitivity of composite materials compared to metallic structures. It also impacts engine fuel consumption associated with removing waste heat from an aircraft. More recently the advent of more electric architectures on aircraft, such as the Boeing 787, has led to increased interest in the development of more efficient ATM architectures by the commercial airplane manufacturers. The ten papers contained in this book describe aircraft thermal management system architectures designed to minimize airplane performance impacts which could be applied to commercial or military aircraft.

The simultaneous operation of all systems generating, moving, or removing heat on an aircraft is simulated using integrated analysis which is called Integrated Energy System Analysis (IESA) for this book. Its purpose is to understand, optimize, and validate more efficient system architectures for removing or harvesting the increasing amounts of waste heat generated in commercial and military aircraft. In the commercial aircraft industry IESA is driven by the desire to minimize airplane operating costs associated with increased system weight, power consumption, drag, and lost revenue as cargo space is devoted to expanded cooling systems. In military aircraft thermal IESA is also considered to be a key enabler for the successful implementation of the next generation jet fighter weapons systems and countermeasures. This book contains a selection of papers relevant to aircraft thermal management IESA published by SAE International.

A new automated production system for installation of Lightweight Groove Proportioned (LGP) and Hi-Lock bolts in wing panels has been implemented in the Boeing 737 wing manufacturing facility in Renton, Washington. The system inserts LGP and Hi-Lok bolts into interference holes using a ball screw mechanical squeeze process supported by a back side rod-locked pneumatic clamp cylinder. Collars are fed and loaded onto a swage die retaining pin, and swaging is performed through ball screw mechanical squeeze. Offset and straight collar tools allow the machine to access 99.9% of fasteners in 3/16″, ¼″ and 5/16″ diameters. Collar stripping forces are resolved using a dynamic ram inertial technique that reduces the pull on the work piece. Titanium TN nuts are fed and loaded into a socket with a retaining spring, and installed on Hi-Loks Hi-Lok with a Bosch right angle nut runner.

In the last several years, the aviation industry has improved its understanding of jet engine events related to the ingestion of ice crystal particles. Ice crystal icing has caused powerloss and compressor damage events (henceforth referred to as “engine events”) during flights of large transport aircraft, commuter aircraft and business jets. A database has been created at Boeing to aid in analysis and study of these engine events. This paper will examine trends in the engine event database to better understand the weather which is associated with events. The event database will be evaluated for a number of criteria, such as the global location of the event, at what time of day the event occurred, in what season the event occurred, and whether there were local meteorological influences at play. A large proportion of the engine events occur in tropical convection over the ocean.

Historically the manufacturing of aircraft fuselages with capacities of 100+ passengers requires large panels and assemblies to be integrated through processes of manipulating them into proper alignment to one another, and then fastening the panels and assemblies together. The manipulating and alignment processes typically incorporate large handling devices and cranes to move the large panels and monolithic tools or measurement alignment systems to precisely align the aircraft components. After the individual panels and assemblies are properly aligned, they can be fastened together. Normally, the fastening process is performed manually with the aid of fastener location templates. There are problems with these processes. They require high capital investments for tooling and facilities; up to two shifts (16 hours) to complete the loading, indexing, and fastening operations; and depend on a highly skilled and knowledgeable work force to minimize discrepancies.

The performance enhancement of a vertical tail provided by aerodynamic flow control could allow for the size of the tail to be reduced while maintaining similar control authority. Decreasing tail size would create a reduction in weight, drag, and fuel costs of the airplane. The application of synthetic jet actuators on improving the performance of the vertical tail was investigated by conducting experiments on 1/9th and 1/19th scale wind tunnel models (relative to a Boeing 767 tail) at Reynolds numbers of 700,000 and 350,000, respectively. Finite-span synthetic jets were placed slightly upstream of the rudder hinge-line in an attempt to reduce or even eliminate the flow separation that commences over the rudder when it was deflected to high angles. Global force measurements on the 1/9th scale model showed that the flow control is capable of increasing side force by a maximum of 0.11 (19%). The momentum coefficient that created this change was relatively small (Cμ = 0.124%).

The Efficient Assembly, Integration & Test (EAIT) team at Boeing Research & Technology, Boeing's central technology organization, is working on multiple implementations of Augmented Reality to aid assembly at the satellite production facility in El Segundo, CA. This presentation will discuss our work to bring an Augmented Reality tool to the shop floor, integrating product design and manufacturing techniques into a synergistic backbone and how this approach can support the delivery of engineering design intent on the shop floor. The team is developing a system to bring designer's 3D CAD models to the technicians on the shop floor, and spatially register them to live camera views of production hardware. We will discuss our work in evaluating multiple motion captures systems, how we integrated a Vicon system with Augmented Reality software, and our development of a user interface allowing technicians to manipulate the graphical display.

A new portable floor drilling machine, the 767AFDE, has been designed with a focus on increased reach and speed, ease-of-use, and minimal weight. A 13-foot wide drilling span allows consolidation of 767 section 45 floor drilling into a single swath. A custom CNC interface simplifies machine operations and troubleshooting. Four servo-driven, air-cooled spindles allow high rate drilling through titanium and aluminum. An aluminum space frame optimized for high stiffness/weight ratio allows high speed operation while minimizing aircraft floor deflection. Bridge track tooling interfaces between the machine and the aircraft grid. A vacuum system, offline calibration plate, and transportation dolly complete the cell.

Current practice for assembly of wing skins to wing stringers utilizes temporary aluminum lock bolts prior to squeeze riveting. Removing and replacing these fasteners is time consuming and hazardous. We have automated the wing riveters to perform this replacement process. This paper discusses the four areas of development that were carried out to accomplish this: tack fastener installation, machine vision system development, drill development and new tooling. Testing results and new findings will be discussed.

Fault-tolerance in commercial aircraft applications is typically achieved by redundancy. In such redundant systems the primary component is checked before the start of a flight to see if it operates correctly. The aircraft will not take off unless the primary is functioning. Airplane manufacturers must certify the airplane systems to be safe for flight. One means of safety certification is by safety analysis which shows that the probability of failure in a typical flight is bounded. The probability bound requirement for a system is based on the criticality of system failure. Usually backup components are checked at intervals that span multiple flights. The first backup may be checked more frequently than the second or higher levels. This leads to flights where the system may have latent faults in the backup components. The probability of failure in such cases varies from flight to flight due to the different exposure times for components in the system.

Over 1,200 large diameter holes must be drilled into the side-of-body join on a Boeing commercial aircraft's fuselage. The material stack-ups are multiple layers of primarily titanium and CFRP. Due to assembly constraints, the holes must be drilled for one-up-assembly (no disassembly for deburr). In order to improve productivity, reduce manual drilling processes and improve first-time hole quality, Boeing set out to automate the drilling process in their Side-of-Body join cell. Implementing an automated solution into existing assembly lines was complicated by the location of the target area, which is over 15 feet (4 meters) above the factory floor. The Side-of-Body Drilling machines (Figure 1) are capable of locating, drilling, measuring and fastening holes with less than 14 seconds devoted to non-drilling operations. Drilling capabilities provided for holes up to ¾″ in diameter through stacks over 4.5″ thick in a titanium/CFRP environment.

The Boeing Company under the teaming agreement with the Northrop Grumman Systems Corporation and in compliance with the NASA Phase 1 contract had the responsibilities for the CEV architecture development of the Environmental Control and Life Support (ECLS) system under the NASA Phase 1 contract. The ECLS system was comprised of the various subsystems which provided for a shirt-sleeve habitable environment for crew to live and work in the crew module of the CEV. This architecture met the NASA requirements to ferry cargo and crew to ISS, and Lunar sortie missions, with extensibility to long duration missions to Moon and Mars. This paper provides a summary overview of the CEV ECLS subsystems which was proposed in compliance with the contract activities.

This paper discusses some of the analytical decisions that an investigator must make during the course of a life support system trade study. Equivalent System Mass (ESM) is often applied to evaluate trade study options in the Advanced Life Support (ALS) Program. ESM can be used to identify which of several options that meet all requirements are most likely to have lowest cost. It can also be used to identify which of the many interacting parts of a life support system have the greatest impact and sensitivity to assumptions. This paper summarizes recommendations made in the newly developed ALS ESM Guidelines Document and expands on some of the issues relating to trade studies that involve ESM.

Clothing accounts for a surprisingly large quantity of resupply and waste on the International Space Station (ISS), of the order of 14% of the equivalent system mass (ESM). Efforts are underway in the ISS program to reduce this, but much greater changes are likely to be possible and justifiable for long duration missions beyond low Earth orbit (LEO). Two approaches are being assessed for long duration missions: to reduce the mass of the wardrobe through use of lighter fabrics, and to clean clothing on board for reuse. Through good design including use of modern fabrics, a lighter weight wardrobe is expected to be feasible. Collateral benefits should include greater user comfort and reduced lint generation. A wide variety of approaches to cleaning is possible. The initial evaluation was made based on a terrestrial water-based washer and dryer system, as this represents the greatest experience base.