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The paper describes the development, implementation, and benefits of a real-time statistical process control (SPC) data acquisition and response system. The system has been installed on four production CNC riveters and provides enhanced, in-process control of automated fastening machine performance. Each system employs commercially available SPC components. These components, coupled with real-time data acquisition computers, have been integrated with the riveter's controllers and sensors to detect process anomalies as they occur. Real-time knowledge of fastening machine performance is the benefit of this system's approach to SPC. Fastener quality is ensured during the fastening cycle, not after sequences (and perhaps hundreds of rivets) have been completed.

The National Aeronautics and Space Administration (NASA) Space Station Freedom (SSF) will use Flow-Through Radiators (FTRs) to reject waste heat that is collected from the on-board Heat Acquisition Devices (HADs). The waste heat is sent to the FTRs via the Pump Module Assembly (PMA) subsystem of the External Active Thermal Control System (EATCS). Two developmental FTR panels were integrated with the EATCS Ground Test Article (GTA). The integrated components were investigated under a thermal/vacuum environment in Thermal/Vacuum Chamber A at NASA/JSC during June, 1992. A detailed SINDA/FLUINT FTR model was developed to predict the steady-state thermal/hydraulic performance of the FTRs. A simplified SINDA/FLUINT FTR model was also developed for use in the GTA integrated model. Schematics and plots comparing the test data and model results are presented for both steady-state and transient conditions.

The Space Constructible Radiator (SCR) Life Test heat pipe performance testing is currently conducted at NASA/Johnson Space Center as part of the Advanced Technology Development Program. The SCR is a dual passage, monogroove heat pipe radiator designed and manufactured by Grumman Aerospace for NASA. The heat pipe has many aerospace applications since it can transport a large amount of heat with a compact lightweight design. As the micro-meteoroid/orbital debris environment worsens, it may be advantageous to add the heat pipe radiator to the Space Station's thermal control system. The SCR Life Test has been operating over the last 10 years and will continue until the year 2000. The overall heat transfer coefficient has decreased from 792 W/K (1500 Btu/Hr-°F) to 475 W/K (900 Btu/Hr-°F) but appears to have stabilized. This paper summarizes the SCR Life Test setup and the test results to date.

The McDonnell Douglas Delta family of launch vehicles, in its more than 30-year history, has proven to be the most reliable spacecraft deployment platform for both the US government and the private sector. This success is due to the continuous and focused application of advanced, affordable engineering and manufacturing technologies in all stages of the design, fabrication, assembly, quality assurance, and launch. One of the recent technological breakthroughs that has enhanced the Delta's service capabilities is the development and use of large composite structures in critical components. Among these structures is the payload fairing, which acts as a protective shroud for the spacecraft. Traditional composite manufacturing techniques, however, are very labor-intensive and time-consuming.

Future military aircraft will demand lower cost and lower weight subsystems that are more reliable, and easier to maintain and support. To identify and develop subsystems integration technologies that could provide benefits such as these to current and future military aircraft, the Air Force Wright Laboratory (WL/FIVE) initiated the Subsystem Integration Technology (SUIT) program in 1991. McDonnell Douglas Aerospace (MDA) together with Pratt and Whitney (PWA), and AlliedSignal Aerospace Systems and Equipment (ASE) was one of three teams that participated in Phase I of the SUIT program. The MDA Team's goal was to conceptually formulate a SUIT approach which would provide significantly reduced weight and costs while increasing cooling and power generation capabilities. These goals were achieved with a new and innovative energy subsystem suite which integrates aircraft and engine subsystem power, cooling, pumping, and controls.

Tactical aircraft have tire lives as low as 3-5 landings per tire causing excessive support costs. The goal of the Improved Tire Life (ITL) program was to begin developing technology to double aircraft tire life, particularly for tactical aircraft. ITL examined not only the tire, but also aircraft/landing gear design, aircraft operations, and the operational environment. ITL had three main thrusts which were successfully accomplished: 1) development of an analytical tire wear model, 2) initiation of technology development to increase tire life, and 3) exploration of new and unique testing methods for tire wear. This paper reports the work performed and the results of the USAF sponsored ITL program.

The Space Station Freedom program requires long-life thermal control coatings that are stable in low Earth orbit (LEO). To provide designers with a variety of coatings and optical properties, improvements were made to existing coatings, and new thermal control coatings were developed. Anodized aluminum was demonstrated to be an acceptable substrate for inorganic thermal control coatings such as Z-93. Mixtures of Z-93 with stable black oxides provided a wide range of optical properties and were stable in a simulated LEO environment. In addition, sulfuric acid anodized aluminum was developed to a production status to provide controlled optical properties for many aluminum alloys.

A method for applying an organic coating to Z-93, an inorganic white thermal control paint, was developed to protect Z-93 from contamination and damage. A layer of FEP Teflon™ was applied over Z-93 to provide a smooth, continuous surface without adversely affecting its optical properties. Additionally, new low-absorptance, controlled-emittance thermal control paints were developed for low Earth orbit (LEO) applications, such as the International Space Station. These paints have a range of infrared emittances from 0.26 to 0.88, and are stable in simulated LEO environments, including atomic oxygen and ultraviolet radiation. Patent applications have been submitted for these concepts.