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This paper presents new concepts for improving management of the electrical load power regeneration of an aircraft. A novel electrical system that allows for load regeneration back to the distribution bus is described. This approach offers the benefits of reduced weight, volume, and cost, as well as improved reliability. Also described is an electrical machine control mechanism that creates motor power to run the prime mover (i.e., the main engine to dissipate the regenerated power). Instead of main engine generation, this approach can be applied to an auxiliary power unit (APU) or power and thermal management system (PTMS). Background information regarding the regeneration concept is presented. The concept definition and the various modes of operation of the improved system are analyzed and described in detail. Results from the dynamic simulation of the system model are included.

SAE ARP 4260 Photometric and Colorimetric Measurement Procedures for Airborne Electronic Flat Panel Displays [1] has recently been revised. This new revision reaffirms that ARP 4260 is pertinent to the aviation industry, changes the content to keep up with the state of the art, and adds clarification where needed. ARP 4260 contains methods used to measure the optical performance of airborne electronic flat panel display systems and is referenced in SAE ARP 4256, Design Objectives for Liquid Crystal Displays for Part 25 (Transport) Aircraft [2] and in SAE AS 8034, Minimum Performance Standard for Airborne Multipurpose Electronic Displays [3].

The power and thermal management system (PTMS) developed by Honeywell for aircraft is an integral approach combining the functions of the auxiliary power unit (APU), emergency power unit (EPU), environmental control system (ECS), and thermal management system (TMS). The next generation PTMS discussed in this paper incorporates the new more electric architecture (MEA) and energy efficient aircraft (EEA) initiatives. Advanced system architectures with increased functionality and further integration capabilities with other systems are included. Special emphasis is given to improvements resulting from interactions with the main engine, main electric power generation, and flight actuation. The major drivers for advancement are highlighted, as well as the potential use of new technologies for turbomachinery, heat exchangers, power electronics, and electric machines. More advanced control and protection algorithms are considered.

This paper discusses the problem of obtaining electric machines (EM) for advanced electric drives (AED) used in more electric architecture (MEA) applicable to aircraft, spacecraft, and military ground vehicles. The AED are analyzed by those aspects of Six Sigma theory that relate to critical-to-quality (CTQ) subjects. Using this approach, weight, volume, reliability, efficiency, and cost CTQ are addressed to develop a balance among them, resulting in an optimized system. The influence of machine controllers and system considerations is discussed. As a part of the machine evaluation process, speeds, bearings, complexities, rotor mechanical and thermal limitations, torque pulsations, currents, and power densities are considered. A methodology for electric machine selection is demonstrated. An example of high-speed, high-performance machine application is shown. A system approach is used for overall electric machine selection and optimization.

Recent advances in the state of the art of space-borne data processors and signal processors have occurred that present some unprecedented constraints relating to their power needs. Such processors include the class of multiprocessors providing computational capabilities in the billions of floating point operations per second. Processors of this type tend to require use of modern radiation tolerant or radiation hardened integrated circuits requiring very low voltage power supplies that place considerable challenge on power distribution and conversion within those processing payloads. The primary challenges are efficient conversion of power from the spacecraft power bus to these low voltages and distribution of the very high accompanying currents within the payload while maintaining proper voltage regulation (typically +/− 5%). Some integrated circuits require 10 Amps or more at 1Volt, as an example [3], [6].

The Internal Thermal Control System (ITCS) has been developed jointly by Boeing Corporation, Huntsville, Alabama and Honeywell Engines & Systems, Torrance, California to meet the internal thermal control needs for the International Space Station (ISS). The ITCS provides heat removal for the critical life support systems and thermal conditioning for numerous experiment racks. The ITCS will be fitted on a number of modules on the ISS. The first US Element containing the ITCS, Node 1, was launched in December 1998. Since Node 1 does not contain a pump to circulate the fluid it was not filled with ITCS fluid until after the US Laboratory Module was installed. The second US Element module, US Laboratory Module, which contains the pumps and all the major ITCS control hardware, was launched in February 2001. The third US Element containing the ITCS, the US Airlock, was launched in July 2001.

The ISS (International Space Station) ITCS (Internal Thermal Control System) includes two internal coolant loops that utilize an aqueous based coolant for heat transfer. A silver salt biocide had previously been utilized as an additive in the coolant formulation to control the growth and proliferation of microorganisms within the coolant loops. Ground-based and in-flight testing demonstrated that the silver salt was rapidly depleted, and did not act as an effective long-term biocide. Efforts to select an optimal alternate biocide for the ITCS coolant application have been underway and are now in the final stages. An extensive evaluation of biocides was conducted to down-select to several candidates for test trials and was reported on previously.

The International Space Station (ISS) IATCS (Internal Active Thermal Control System) includes two internal coolant loops that use an aqueous based coolant for heat transfer. A silver salt biocide was used initially as an additive in the coolant formulation to control the growth and proliferation of microorganisms in the coolant loops. Ground-based and in-flight testing has demonstrated that the silver salt is rapidly depleted and not effective as a long-term biocide. Efforts are now underway to select an alternate biocide for the IATCS coolant loop with greatly improved performance. An extensive evaluation of biocides was conducted to select several candidates for test trials.

In response to consumer demand, automakers are adding more safety, security, and convenience features to vehicle access control systems. Also, in a continuing effort to be more profitable, automakers are reducing costs by outsourcing the design of systems/sub-systems/components, reducing their supply base, and minimizing part numbers by sharing components across several platforms. In an attempt to improve efficiency and productivity, many OEM's have adopted a “corporate latch” strategy, implementing the same latch across several manufacturing platforms and marketing divisions. Honeywell's revolutionary door latch design efficiently and cost effectively addresses vehicle OEMs' current and future requirements for performance and functionality.

Previously we reported to the SAE 2000 basics in selection of various colored and un-colored/natural nylon 6 (polyamide - PA 6) based plastics for laser welding technology. Later we presented to Antec1 2001 and to SAE 2002 our developments of colored in black through-transmissible grades of PA 6 plastics, which were specially tailored for the specifics of the design and laser welding technology. In this current paper, we will try to enhance the understanding of the engineering community regarding the usefulness and applicability of laser welding technology, developed colored thermoplastics, and its increasing use in various automotive and transportation applications.

Previously we reported to the SAE'99 our findings on selections of nylon (polyamide) based plastics for laser welding (LW) technology. In this current paper, we will try to increase the understanding of the engineering community regarding the usefulness and applicability of an advanced LW technology (and developed thermoplastics), and its increasing use in various automotive applications.

Honeywell Engines and Systems (E&S) Environmental Control Systems (ECS) division has been developing a 50 kW proton exchange membrane (PEM) fuel cell brassboard system for automotive application as part of a U.S. Department of Energy (DOE) program. A primary issue in the development of the brassboard is the automatic control of the system. A preferred DOE requirement is dynamic load following from idle to peak power. Since the PEM stacks require precise inlet condition control for both the air and fuel to achieve high efficiency, the control system must provide good dynamic tracking and low steady-state error over the entire operating range. In addition, the controller must provide automatic system start-up and shutdown, built-in-test (BIT) to monitor key system parameters, and take corrective action if those parameters reach an unsafe condition. The purpose of this paper is to present the control system design approach taken by the authors to achieve those goals.

The International Space Station (ISS) internal thermal control system (ITCS) has been developed jointly by the Boeing Corporation, Huntsville, Alabama, and Honeywell Engines & Systems, Torrance, California, to meet ISS internal thermal control needs. The ITCS provides heat removal for the critical life support systems and thermal conditioning for numerous experiment racks. The ITCS will be fitted on a number of modules on the ISS. The first module, the US Laboratory Module, was launched in February 2001 and is now operational on the ISS. The dual loop system is comprised of a low-temperature loop (LTL) and a moderate-temperature loop (MTL). Each loop has a pump package assembly (PPA), a system flow control assembly (SFCA), a three-way mixing valve (TWMV), several rack flow control assemblies (RFCA), cold plates, pressure sensors, temperature sensors, a pump bypass assembly (PBA), and a heat exchanger.