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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.

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.

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.

Flight testing of aircraft under natural icing conditions can be extremely tedious, time consuming, costly, and somewhat risky. However, such testing has been required to demonstrate the effectiveness of anti-icing systems and to certify new aircraft models. To reduce the need for extensive flight testing, Boeing has built a new icing tunnel that has the capability for developing ice shapes and evaluating anti-icing features on full scale sections of critical parts of the aircraft. The icing tunnel was made by modifying an existing 5 ft by 8 ft Boeing Wind Tunnel to add icing capabilities. This paper describes the design specifications, the tunnel capabilities, and the major equipment systems and presents the results of the tunnel calibration relative to the specified requirements.

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.

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.

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.

This paper addresses the question of whether automation is being used in the proper applications in aircraft in order to maximize aircraft capabilities and make the most of human performance capacity. It is believed that the aircraft designers, while employing automation, have given due regard to the pilot's role as operator and manager of the aircraft. There does, however, seem to be valid concern for the human element in certain aspects of the air traffic control system.

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.

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.

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.