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The variable-geometry features of the United States supersonic transport are described. Particular attention is given to the hardware development of those variable-geometry features unique to the supersonic transport. The design, development, and current status of a direct lift control sys tern, the supersonic internal-external compression inlet, and the full-scale wing pivot are described.

The interactive and cyclical design, evaluation, and operational system that conceives transport airplanes is described. Some economic consequences of preliminary design variable choices are displayed, followed by an inspection of the 1967 ATA Method and actual direct operating costs. Uses and misuses of the formula costs, as compared to actual cost levels, are considered. Finally, the impact of airplane choice on airline profitability is examined. It is seen that the profit consequences are great enough to require careful attention to economic trades in every step of the design, evaluation, and operational process.

The International Space Station (ISS) Temperature and Humidity Control (THC) system has been designed with the intent of supplying the air cooling needs of various elements from the U.S. Lab heat exchanger assembly. Elements without independent air cooling capability are known as “parasitic” elements; these are Node 1, the Cupola, and the Mini Pressurized Logistics Module (MPLM). Analysis results are presented which show expected temperatures in the MPLM, and Node 1, as various heat loads are present in the respective elements. Analyses within this paper are coordinated with the results obtained from the Development Test of the complex USL/Node 1 integrated ducting system. This test was conducted in the summer of 1995, at the McDonnell Douglas test facility in Huntington Beach, California.

Traditional thermal design criteria for avionics equipment are reviewed. Several studies have recently been conducted on the F-15 to assess accuracy of these design criteria. An overview of the study approach and results are presented. Specific topics investigated include: emergency cooling air provisions, cold start-up, hot start-up, normal and transient bay temperatures, and altitude design. The results indicate that many existing design criteria are overly conservative. The study findings suggest that reform of the existing thermal specification process is needed. Many of these reforms are applicable to the general aerospace industry and may result in significant acquisition cost savings as a result of the trend toward usage of commercial electronic parts. The reforms suggested include a new performance based thermal specification approach that increases emphasis on aircraft usage and frequency of occurrence. New transient design criteria are also recommended.

The International Space Station (ISS) Temperature and Humidity Control/Intermodule Ventilation (THC/IMV) system for the U.S. Lab provides required cooling air for the U.S. Lab and also provides “parasitic” cooling air for Node 1 and its attached elements. This scheme provides cooled air from the Lab THC directly to Node 1 and also to elements attached to Node 1, at different stages of Space Station assembly. A development test of the U.S. Lab and Node 1/attached elements' integrated THC/IMV ducting system was performed in the summer of 1995. This test included the U.S. Lab's development level Common Cabin Air Assembly (CCAA), which removes sensible and latent heat from the circulated and ducted cabin air. A referenced 1996 ICES Paper contains the initial correlation results. An analytical model has been developed, which has been used to predict flow and pressure drop performance of the system for several potential and actual changes from the Development Test configuration.

The International Space Station (ISS) Temperature and Humidity Control/Intermodule Ventilation (THC/IMV) system for the U.S. Lab provides required cooling air for the U.S. Lab and also provides “parasitic” cooling air for Node 1 and its attached elements. This scheme provides cooled air from the Lab THC directly to Node 1 and also to elements attached to Node 1, at different stages of Space Station assembly. This paper reports on the results of Open Hatch ECLSS/ TCS Tests for International Space Station’s Lab Module. The hardware tested is referred to as proto-flight hardware. Upon satisfactorily passing these Open Hatch and later Closed Hatch, imposed ground based, proto-flight tests, the proto-flight hardware will become flight hardware. The Lab Module is scheduled for launch during late 1999. The particular ECLSS/TCS equipment discussed here are the Temperature Humidity and Control (THC) equipment and Intermodule Ventilation (IMV) equipment.

This paper addresses process improvements through reality graphics (RG) aided by automated panel protection (APP) and tool kitting pertaining to automated wing riveting and fastening. This system provides an integrated display of numerical controlled media, automatic tool identification, and image files, combined with automated panel protection. Reality graphics (image files) within the NC program allow the machine operator to access portions of the NC program while attaching a support graphic. This would include safety hazards, unique panel differences, program start, and tool change information. Automated panel protection (APP) analyze process key characteristics, and perishable tool kits, and it monitors the installation of fasteners using multiple cameras mounted in strategic positions, taking real-time images. The APP detects incorrect tooling and possible panel damage, with little or no impact to the operational cycle time of the automated fastening equipment.

This paper discusses some of the problems of developing and maintaining equipment containing integrated circuits. The problems discussed fall into three categories: (1)Processing, (2) Fault Isolation, and (3) Human Error. Quantitative study of these problems shows the highest number were experienced during preliminary-manufacturing and testing (screening and burn-in), with a decrease during final manufacturing checkout (board assembly and final testing) and a minimum during the system operational period. The paper concludes that maintainability is still the necessity it was even with the advent of reliable integrated circuits. This is substantiated by the many failures and defects encountered during manufacturing and development phases. Manufacturing economics force the consideration of maintainability in integrated circuit design.

In this lecture, a review of Boeing commercial transport models is presented in chronological order from the B-1 flying boat of 1919 to the 747. The problems of air transport systems including convenience, reliability, safety, comfort, performance, and financial and environmental costs are discussed. The probability of more severe future problems is considered, and suggestions are offered as to technology and system improvements which may need to be pursued if civil air transport systems are to continue to provide fast, convenient transportation with a high level of public acceptance.

A discussion of wing-nozzle configuration development for the application of upper surface blowing to a STOL airplane is presented. The technical challenge is to achieve an integrated system which provides the desired performance for the low speed design conditions and also results in efficient operation during cruise. The resulting configuration is a complete integration of the propulsion system and airplane aerodynamics to achieve efficient operation at all regimes. This paper examines the major design parameters to be considered, describes a number of the configurations tested, and presents static and wind tunnel test results for these configurations. Concluding remarks are made relative to USB nozzle development.

A loosely coupled method for aeroelastic predictions of aircraft configurations is shown. This method couples an advanced structural analysis method with a CFD aerodynamics code in a modular fashion. This method can use almost any CFD code, so a validation of several such codes is shown to establish regions of validity for each code. Results from potential codes, an Euler code, and a Navier-Stokes code are shown in comparison with experiment. Viscous effects are included in most cases through a coupled boundary-layer solver or a turbulence model as appropriate.

Many mechanical systems employing fluid power use one or more valves to control fluid flow. Often these valves can be quite complex, with many inlets and exits, reversing flow, flow and pressure control, and other unique features. It is desirable to model these valves and the associated fluid and control logic circuits with software during the design phase, and explore the effect of design changes on system performance using simulation and other analyses without having to build and modify expensive prototypes. A number of commercially available software packages offer various methods for “graphically modeling” dynamic systems, and some, offer the user pre-defined libraries of hydraulic components that greatly speed the modeling process. However, the variations on valve design are unlimited, and it is often necessary to model a hydraulic valve that has not been previously defined. This paper describes an approach allowing essentially any valve configuration to be modeled.

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.

Over 200 International Space Station external high maintenance items have been designed for replacement by a dexterous robotics system in addition to space-suited astronauts. Planning for dexterous robotics maintenance increases flexibility for space station operations with a robot able to execute many tasks in place of a suited crew member, lowering the number of hours crew must spend on Extravehicular Activity (EVA). The five inboard truss segments of the station - S3, S1, S0, P1 and P3 - include 122 of these robot compatible maintenance items or On-orbit Replaceable Units (ORUs). This paper describes the impact robotic compatibility has had on the International Space Station (ISS) design, reviewing the inboard truss items as examples. Diverse challenges exist to verify each genre of ORU meets the dexterous robotics requirements.

A successful methodology was developed at Boeing Company to investigate hot-gas ingestion in vertical take-off and landing aircraft. It involves sub-scale model testing using specialized test facilities and test techniques. The baseline characteristics of hot-gas ingestion (HGI) and the performance of various HGI reduction techniques were qualitatively evaluated in the Boeing Hover Research Facility. Potential HGI reduction devices were then further tested at scaled pressures and temperatures in HGI facilities at NASA Lewis, Rolls Royce and British Aerospace. One of the successful HGI reduction devices was flight tested. This paper describes the application of Boeing HGI reduction methodology to three specific aircraft configurations.

Three separate and distinct electrolytic and one galvanic process were identified by visual inspection, metallographic, electron microprobe, and x-ray diffraction analysis in a clocked, flip-flop integrated circuit flat pack and/or the associated printed circuit test jig (two on flat pack and two on circuit board). These four processes were all found to be detectable by the use of noise measurements in microvolts per root cycle at 1000 Hz (cycles per second). The direct current applied for noise measurement to the integrated circuit devices was 100 micro-amperes, as compared to the 6-8 milliamperes required for normal operation. After initial experimentation, the devices were caused to fail in a laboratory ambient environment, followed by an acceleration of the rate of electrolytic reaction through the use of essentially 100 percent relative humidity, versus the upper specification limit of 80 to 98% relative humidity.

The traditional method of determining the net thrust of an engine in cruise is explained. It is shown to result in a satisfactory net thrust uncertainty for jet and low bypass ratio engines but to be unsuitable for high bypass ratio engines. A redefinition of net thrust results in a new thrust determination method, called continuity method, which yields acceptable levels of net thrust uncertainty. The new method no longer requires supporting tests in a simulated altitude facility. The question is raised whether in future programs the demonstration of guaranteed cruise performance of an engine should not be carried out in flight tests rather than in an altitude test facility.

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.

The evolution of a manufacturing organization toward “Lean” manufacturing does not necessarily come cheaply or quickly. It is the experience at Boeing that technology and different visions can dramatically impact the evolutionary process-consuming great amounts of time and resources. The Boeing of Spokane case study, where aircraft floor panels are manufactured1, is but one of several case studies that suggests moving to “Lean” manufacturing is usually done in large steps, not small ones. These initial steps can be costly unless the systems (equipment and workforce) are flexible. Workforce flexibility is dependent on the attitude in the workforce as both touch and support labor move from their comfort zone to try new approaches and job descriptions. The workforce must be properly motivated to make the change. The equipment must also be flexible in adapting to new line layouts, product mixes, and process change or large cost penalties will be incurred.

There are a large number of space structures, orbital replacement units (ORUs) and other components that must be transported to orbit on a regular basis for the assembly and maintenance of the International Space Station (ISS). Some of this hardware will be ferried on the Spacelab Logistics Pallet (SLP), which has a long and reliable history of space flight successes. The carrier is well used, well qualified, and very adaptable for repeated use in accommodating cargoes of various sizes and shapes. This paper presents an overview of past, present and future hardware design solutions that accommodate EVA operations on the SLP. It further demonstrates how analysis techniques and design considerations have influenced the hardware development, EVA operations, and compliance with human engineering requirements for the SLP.