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The need for achievement of low community noise levels has had a major influence on the configuration selected for the United States Supersonic Transport (Boeing 2707-300). The selection and development of design features which affect community noise are presented. The configuration has a relatively large span delta wing of moderate sweep and wing loading, with full span leading and trailing edge flaps. An all moving horizontal tail with geared flap is used for trim and control. The use of an unusually far aft center of gravity range is achieved through a fulltime stability augmentation system. All of these design features contribute to low drag at high lift, resulting in high takeoff performance and low levels of thrust required during flight over the community during both takeoff and landing. The resulting airplane has the versatility to use operational techniques which further reduce noise.

Passengers and flight attendants often notice a haze of smoke under the overhead stowage bins in aircraft cabins when cigarette smoking is allowed. As normally operated, the ventilation system in Boeing 737/757 aircraft does not rapidly remove this smoke haze. Air ionization systems from three vendors were tested in a 10 foot long Boeing 737/757 cabin test section with a cruise condition ventilation rate and two cigarette smoking rates to assess their effectiveness in removing smoke haze from the local breathing areas of passengers and flight attendants. Smoke particulate densities were monitored at five breathing areas and at an exit grill in the test section. All of the ionization systems significantly increased the rate of smoke removal after smoking had stopped, increasing the removal rate by about 25%. None of the systems showed a statistically significant reduction of smoke levels at the individual monitoring points while cigarettes were being smoked.

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.

A concerted, systematic program for design and development of a high reliability booster has been developed by The Boeing Co. for use in the NASA Apollo Manned Space Flight Program. The S-IC program stressed discipline in analysis, testing, and management to insure a consistent and reliable end product. Evaluation of the operational experience from this program resulted in a complete systems analysis program being established which encompassed single-point failure mode and effect analysis, double-point failure mode and effect analysis, and analysis of potential human-initiated failures. These activities serve to predict stage reliability, identify reliability critical components, and provide a constant feedback to design and management to permit timely hardware redesign, retesting or revision to operating procedures to eliminate or minimize the probability of failure.

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.

The process of developing a Payload Attach System (PAS) which will support a wide range of experimental and commercial payloads on the International Space Station (ISS) has experienced an interesting evolution during its design, development, test and evaluation (DDT&E) phase. This evolution has been caused in large measure by requirements intended to insure compatibility of the PAS with the extravehicular activity (EVA) crewmember during nominal and contingency operations in and around the PAS sites. As the design of the ISS transitioned from its Freedom predecessor, the effort to keep costs down by preserving as much of the original Freedom design as possible led to design decisions that challenged engineering thinking.

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.

The effects of meteoroid protection weight requirements on space exploration costs are examined. A basis is developed for selecting upper and lower bounds to the acceptable risk. The quality of present knowledge of the meteoroid environment and of hypervelocity impact penetration is reviewed. This information is synthesized and criteria are developed that are suitable for selecting methods of designing simple and composite barrier systems. Techniques are established for controlling damage to spacecraft components. Short and long term goals are recommended to improve present design capability.

New manufacturing technologies such as high speed machining (HSM) are being developed to produce high quality aerospace components. While our developing understanding of machining dynamics is enabling precise control of cutting tools to provide for high dimensional accuracy, residual stresses present in aluminum mill products can compromise the ability to machine dimensionally accurate components from these stock materials. The advantages of precise tool control can be lost if the metal being cut moves during machining. And, even a perfectly machined part that distorts when it is released from the machine bed will cause problems upon assembly. Thus, ensuring the quality of the mill product becomes an enabling technology for advanced manufacturing approaches such as HSM.

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.

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.

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.

The Boeing F/A-18 E/F Program Wing Team, Lean Organization and Phantom Works have partnered to develop a “state of the art” lean production system for the Outer Wing that represents an evolutionary change in aircraft design and assembly methodology. This project is focused on improving quality, cycle and cost performance through the implementation of lean principles, technology integration and process improvements. This paper will discuss the approach taken to reach the end state objectives and the technologies and processes being developed to support it. Items to be discussed include lean principles and practices, new tooling concepts, improved part assembly techniques, advanced drilling systems, process flow enhancements and part handling/part delivery systems.

The Boeing Aero Grid and Paneling System (AGPS) is a programming language with built-in geometry features. Accessible through either a graphical user interface (GUI) or through a command line, AGPS can be used by operators with different levels of experience. Distributed with AGPS are approximately 300,000 lines of macros, or command files, which automate many engineering design and analysis tasks. Most command files were developed to produce inputs to engineering analysis codes such as A502 [1] and TRANAIR [2]. In many cases, command files have been grouped together in AGPS “packages,” which offer users simple menu pick and dialog options to automate entire engineering processes.

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.

High maintenance costs of the three 40,000 lb. thrust class aircraft engines manufactured by Pratt and Whitney, General Electric, and Rolls-Royce are discussed. Primary emphasis is on existing engine problems which contribute to high shop visit rate. Maintenance cost in terms of monetary value is not discussed. Concludes that increased emphasis on total life cycle durability is necessary by the engine manufacturers. Recommends higher level of priority be given durability in design and analysis, pre-production proof-of-design testing, and engine program management.

Two spindles are discussed in this paper. The first spindle was installed on nine C-frame riveters on the 737/757 wing line at the Boeing Renton facility. Due to discontinuing the use of Freon coolant and cutting fluid, the C-frame riveters had difficulty shaving 2034 ice box rivets with the existing 6000 RPM hydraulic spindles. The solution was to install electric 30,000 RPM shave spindles inside the existing 76.2 mm (3 in.) diameter hydraulic cylinder envelope. The new spindle is capable of 4 Nm (35 in. lbs.) of torque at full speed and 110 kgf (250 lbs.) of thrust. Another design of interest is the Electroimpact Model 09 spindle which is used for 20,000 RPM drilling and shaving on wing riveting systems. The Model 09 spindle is a complete servo-servo drilling system all mounted on a common baseplate. The entire spindle and feed assembly is only 6.5″ wide.

This study examines the lunar environment, the lunar rover mission, and the factors that influence EMU walkback range in the event of a rover failure many kilometers from base. A heuristic method to estimate walkback range of EVA astronauts is presented. An attempt is made to quantify the EVA walkback factors that influence the total walkback range of the lunar EVA astronaut given a fixed duration of the EMU. A walkback range estimate can then be used to carefully structure EVA missions and will help in future designs of EMUs.