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Understanding the friction behavior of brake lining materials is fundamental to the ability to predict brake system performance. Of particular interest to the aviation community, where carbon/carbon composite heatsinks are commonly used, is the aircraft response at deceleration onset. There are two performance measures defining brake system performance at braking onset: deceleration onset rate and system response time. The latter is strictly a function of the brake system hydraulics and is not affected by brake lining friction. The former performance measure is a function of both system hydraulics and brake lining friction. Previously to the work herein, carbon heatsink friction was thought to be unpredictable at braking onset. That being the case, a predictive capability for deceleration onset rate was not previously undertaken. This meant that assessment of this performance measure waited until aircraft taxi tests were performed.

The new 757/767 transports will be the first Boeing Commercial aircraft to commit advanced graphite composite material to initial production. Composite materials, mainly fiberglass in an epoxy matrix, have been used in Boeing military and commercial aircraft in ever increasing amounts for the past twenty (plus) years. Recently, the state-of-the-art of Advanced Composites (graphite and graphite/Kevlar hybrids in an epoxy matrix) progressed to the level that it could be committed to full-scale production. This production commitment resulted in a multi-year, multi-million dollar development program. This was to assure technical and production readiness, and product reliability to meet the stringent performance and safety standards of modern commercial transport.

Assembly techniques for the majority of expendable and reusable launch vehicles have not changed much over the last thirty years. Some progress has been made, specifically on new programs, however, improvements on existing expendable launch vehicle production lines can be difficult to justify; even more so for one or two reusable vehicles. This presentation will focus on techniques and systems used for manual and automated assembly of expendable and reusable launch vehicle primary structures. Today's assembly is characterized by manual operations involving fixtures and templates, and all tasks are carried out primarily with single function hand tools. Typical assembly approaches used for metallic and composite primary structures will be discussed. Potential opportunities for process improvements utilizing advanced hand tools, mechanized and/or automated equipment will be addressed.

Space Station Freedom (SSF) has an extended mission duration of 30 years. Trade studies for extended missions of manned spacecraft almost invariably show that large resupply weight and consequent cost savings can be achieved by recovering potable water from wastewater sources. This rationale has led to the present baseline Water Recovery and Management (WRM) system for the Permanently Manned Capability (PMC) phase of SSF. The baseline WRM includes the Vapor Compression Distillation (VCD) subsystem for recovering water from urine. This process serves as a preliminary processing step in achieving potable water from wastewater sources. The basic principle of the VCD is that water is evaporated from urine and then condensed in a zero-gravity device containing an evaporator and a condenser in a rotating drum. The VCD was selected for the baseline WRM following the assessment of test results from competitive urine processing subsystems obtained from the Comparative Test (CT) program.

At The Boeing Company, the advent of a Determinant Assembly (DA) program and the subsequent production of accurate fuselage subpanels created a need to be able to position subpanels accurately and repeatably during fuselage assembly. The tool engineering organization of The Boeing Company and Advanced Integration Technology, Inc. (AIT) as the prime contractor, are developing and installing automated positioning and alignment systems throughout major 747 fuselage assembly areas which enable DA techniques. The benefits of this assembly approach and this automated precision tooling are flexibility, assembly accuracy, ease of assembly and associated speed, reduced downtime for tool maintenance, and improved shop-floor ergonomics.

Aircraft manufacturing in the 21st century sees a future much different to that seen one and two decades before. Manufacturers of both military and commercial aircraft are challenged to become Lean, Agile and Flexible. As progress is slowly made toward introducing advanced assembly systems into production, the overall cost of automation is now more closely scrutinized. After spending tens of millions of dollars on large automated systems with deep foundations, many manufacturers find themselves locked into high cost manufacturing systems that have specific, inflexible configurations. This kind of scenario has caused a shift in the attitude of airframe assemblers, to go back to basics. Lean manufacturing is seen as a way to build aircraft with very low investment in equipment and tools. Today's advanced systems developers do understand the need for more affordable assembly systems.

This paper presents a detailed overview of the advantages and benefits of using 2-D barcodes, called Data Matrix codes, on Wing Fastening System (WFS) Tooling. This project was conducted on, but not limited to, the 777 Wing Fastening System (GEMCOR) tooling including the drills, fingers, and button dies. This paper will show how using Data Matrix codes to identify tooling will: Eliminate excessive downtime due to the operator using the incorrect tooling for a given tool setup. Reduce the cost associated with panel rework due to the use of incorrect tooling. Reduce the cost associated with excessive tool inventory or last minute ordering to keep up with production needs. Track tool life information for each specific tool. Provide operators with an easy to use tool setup reference document. And provide the factory with the ability to trace panel damage or defects back to the specific machine and exact tooling used.