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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.

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.

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.

Drilling fastener holes in large assemblies is traditionally accomplished through the use of large machine tools in order to obtain the accuracies required for the assembled part. Given recent advances of machine design and machine controller compensation, the accuracy of the motion platform can be corrected if the machine is repeatable. This coupled with the use of a vision system or touch probe to compensate for assembly variations, permit the use of smaller, more portable drilling systems. These smaller, more portable machine tools allow for lean manufacturing techniques to be incorporated into build processes, utilize less floor space, and in many cases are less costly than larger, permanent machine tools. This paper examines the feasibility of utilizing a small 5-axis, portable, drilling system for drilling the side panel skins on the F/A-18 E/F forward fuselage.

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.

A hydraulic squeeze riveting process has been developed which yields high fatigue quality for large diameter rivets in aluminum wing structure. The process for installation of 7/16 inch diameter 2017-H15 aluminum alloy flush head rivets was developed using a series of statistically designed experiments. Factors such as rivet geometry, die shape, and upset force were varied to yield optimal rivet interference. The relationship between interference and fatigue life was quantified. The development process described provides a case study for those working to optimize complex multivariate manufacturing processes.

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.

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.

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 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.

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.