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The experimental procedure employed to define the natural modes of vibration of the 747 Shuttle Carrier Aircraft and Space Shuttle Orbiter mated configuration is described. A discussion of test results and comparison to structural analysis results is also included. Random transient signals were used as inputs to electromagnetic shakers to provide excitation to the mated vehicle test configuration. Acceleration signals were processed via the Fast Fourier Transform algorithm. Magnitude and phase transfer functions were formed and processed to produce modal frequencies, damping, and modal displacements.

The purpose of this paper is to provide a general process for human model analysis in the digital mock-up environment. It is also intended to provide some basic guidelines for the use and application of human models. This document is intended for anyone who will be performing human model analyses. It is assumed that the person performing the analysis has at least a minimal level of training in the use of the software involved. Note that this document is limited to anthropometric and ergonomic modeling.

The joint development of an augmentor wing jet STOL research aircraft by NASA and the Canadian Government Department of Industry, Trade, and Commerce has progressed to the point that the design of the modifications to the de Havilland C-8A Buffalo are complete and the engines are being tested. The predicted performance shows that the airplane will be able to take off and land in less than 1500 ft. Simulation studies indicate that the handling qualities of the airplane, with stability augmentation, will be acceptable for STOL research missions.

Since the advent of the turbojet engine, there has been much research by aircraft and engine manufacturers into the source of aircraft noise and its reduction. A review of this research is presented delineating the transition from turbojet engines to turbofan engines to the high by-pass ratio engines being introduced today, and the progress that has been made. Application of the current state-of-the-art to existing airplanes through engine replacement, nacelle retrofit, and flight procedures are also discussed.

The utility of airplane flow-field measurements for wind-tunnel testing is reviewed. The methods and equipment developed at Boeing for these measurements are also described. The details of the latest system are presented along with typical results from recent wind-tunnel tests. Using the latest system, flow-field surveys of airplane configurations in industrial low-speed and transonic wind tunnels provide spatial distributions of lift and drag (profile and induced) with good repeatability. In addition, the probe speed and survey region is optimized so that typical full-wake surveys take 20-30 minutes to complete. Final data, displayed as total pressure, velocity vectors, vorticity contours, and distributions of lift and drag (profile and induced) are available approximately 10 minutes after survey completion.

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.

During a recent International Space Station (ISS) flight (Flight 2A.1), an improper ventilation event might have occurred and resulted in stuffy air, as reported by the crew. Even though no air samples were analyzed, the accumulation of metabolic CO2 in the ISS was suspected as the cause of the crew sickness. With no possibility of conducting an on-orbit test of this kind, it was decided to utilize Computational Fluid Dynamics (CFD) analysis to investigate this problem. Based on the Flight 2A.1 and 2A.2a configurations, a CFD model of the air distribution system was built to characterize airflow between the ISS elements. This model consists of Inter-module Ventilation (IMV) covering the Functional Cargo Block (FGB), two Pressurized Mating Adapters (PMA-1 and PMA-2), the Node-1, and portions of the Orbiter volume.

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.

An overview of composite structure required for manned orbiting space stations is presented. Following a brief introduction of typical configurations and major subsystems, the major structural areas requiring composite structure and their particular functions and requirements are discussed. A summary weight breakdown is presented to assess the dependence of launch weight on these areas. To illustrate, the primary wall composite structure is presented in detail. The design interplay of boost, pressure, meteoroid, radiation, and thermal control requirements are presented. Resultant composite structure for each remaining major structural area is presented in summary form with a brief description of typical design compromises required.

Fastener selection entails two functions, a staff function to select a group of fasteners for consideration and a design function to select the most suitable fastener for a specific function. This paper itemizes in detail the considerations that enter into each function in selecting fasteners for commercial and military aircraft, military unmanned vehicles, and space vehicles. Characteristics of specific bolts and fasteners are also tabulated.

A considerable amount of integrated Environmental Control and Life Support System (ECLSS) analysis has been performed and documented for the proposed habitable Space Station. Earlier analytic activities have resulted in highly refined models simulating Temperature and Humidity Control (THC) and Atmosphere Revitalization (AR) hardware. As the mechanisms by which these items affect the Space Station environment have become better understood (along with the effects due to operation of various Man Systems utilities), the next stage of the integrated analysis task has been accomplished; i.e., the simulation of the Atmosphere Control and Supply (ACS) subsystem. The focus of the present paper is upon the ACS function in the overall life support system. Modeling of the ACS is unique among the life support disciplines in that it requires accurate representation of all other ECLSS subsystems that interact with the cabin atmosphere (which has now been achieved) in order to be realistic.

This paper reviews the recent G189A computer program developments in the area of humidity control for the U.S. Lab Module in the Space Station. The humidity control function is provided as an indirect or passive function by the Common Cabin Air Assemblies (CCAA) in pressurized elements or modules in the Space Station. The CCAAs provide active cabin temperature control through implementation of a digital/electromechanical control system (i.e., a proportional/integral (PI) control system). A selected cabin temperature can be achieved by this control system as long as the sensible and latent heat loads are within specified limits. In this paper three pertinent analytical cases directed to determining minimum or maximum dew point temperatures are discussed. In these cases the basic sensible heat loads are set at constant values.

A review of the current extended-range twin-engine operations (ETOPS) and the modifications to the standards and processes that led to its successful operational record has contributed to the feasibility of developing an airplane and preparing an operator for ETOPS at entry into service. The airplane and engine manufacturers and component suppliers have continued to expand on these modified standards and processes in their design, build, test and support programs to meet regulatory authority ETOPS requirements and to facilitate the development of regulatory authority criteria for substantiating ETOPS capability prior to entry into service. Airlines, in conjunction with the manufacturers, have also developed improved processes that meet regulatory authority requirements for preparing an operator to integrate a new airplane into its existing ETOPS programs at entry into service.

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.

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.

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.

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 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 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.

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.