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This talk will present an overview of the newly published DO-326/ED-202 "Airworthiness Security Process Specification". Presenter Daniel P. Johnson, Honeywell

Health Ready Components are essential to unlocking the potential of Integrated Vehicle Health Management (IVHM) as it relates to real-time diagnosis and prognosis in order to achieve lower maintenance costs, greater asset availability, reliability and safety. IVHM results in reduced maintenance costs by providing more accurate fault isolation and repair guidance. IVHM results in greater asset availability, reliability and safety by recommending preventative maintenance and by identifying anomalous behavior indicative of degraded functionality prior to detection of the fault by other detection mechanisms. The cost, complexity and effectiveness of the IVHM system design, deployment and support depend, to a great extent, on the degree to which components and subsystems provide the run-time data needed by IVHM and the design time semantic data to allow IVHM to interpret those messages.

Atmospheric Neutron Single Event Effects (SEE) are widely known to cause failures in all electronic hardware, and cause proportionately more failures in avionics equipment due to the use altitude. In digital systems it is easy to show how SEE can contribute several orders of magnitude more faults than random (hard) failures. Unfortunately, current avionics Safety assessment methods do not require consideration of faults from SEE. AVSI SEE Task Group (Aerospace Vehicle Systems Institute Committee #72, on Mitigating Radiation Effects in Avionics) is currently coordinating development of an atmospheric Neutron Single Event Effects (SEE) Analysis method. This analysis method is a work in progress, in close collaboration with SAE S-18 and WG-63 Committees (Airplane Safety Assessment Committee). The intent is to include this method as part of current revisions to ARP4761 (Guidelines and Methods for Conducting the Safety Assessment Process on Civil Airborne Systems and Equipment).

As the US is getting ready for the Next Generation (NextGen) of Air Traffic System, there is a growing concern that the current techniques for verification and validation will not be adequate for the changes to come. The JPDO (in charge of implementing NextGen) has given NASA a mandate to address the problem and it resulted in the formulation of the V&V of Flight-Critical Systems effort. This research effort is divided into four themes: argument-based safety assurance, distributed systems, authority and autonomy, and, software intensive systems. This paper presents an overview of the technologies that will address the problem.

Natural atmospheric radiation effects have been recognized in recent years as key safety and reliability concerns for avionics systems. Atmospheric radiation may cause Single Event Effects (SEE) in electronics. The resulting Single Event Effects can cause various fault conditions, including hazardous misleading information and system effects in avionics equipment. As technology trends continue to achieve higher densities and lower voltages, semiconductor devices are becoming more susceptible to atmospheric radiation effects. To ensure a system meets all its safety and reliability requirements, SEE induced upsets and potential system failures need to be considered. The purpose of this paper is to describe a process to incorporate the SEE analysis into the development like-cycle. Background on the atmospheric radiation phenomenon and the resulting single event effects, including single event upset (SEU) and latch up conditions is provided.

The Energy Finite Element Analysis (EFEA) has been utilized successfully for modeling complex structural-acoustic systems with isotropic structural material properties. In this paper, a formulation for modeling structures made out of composite materials is presented. An approach based on spectral finite element analysis is utilized first for developing the equivalent material properties for the composite material. These equivalent properties are employed in the EFEA governing differential equations for representing the composite materials and deriving the element level matrices. The power transmission characteristics at connections between members made out of non-isotropic composite material are considered for deriving suitable power transmission coefficients at junctions of interconnected members. These coefficients are utilized for computing the joint matrix that is needed to assemble the global system of EFEA equations.

Silver biocide offers a potential advantage over iodine, the current state-of-the-art in US spacecraft disinfection technology, in that silver can be safely consumed by the crew. As such, silver may reduce the overall complexity and mass of future spacecraft potable water systems, particularly those used to support long duration missions. A primary technology gap identified for the use of silver biocide is one of material compatibility. Wetted materials of construction are required to be selected such that silver ion concentrations can be maintained at biocidally effective levels.

Carbosieve SIII was used to filter dichloromethane (DCM) from a simulated spacecraft gas stream. This adsorbent was tested as a possible commercial-off-the-shelf (COTS) filtration solution to controlling spacecraft air quality. DCM is a halocarbon commonly used in manufacturing for cleaning and degreasing and is a typical component of equipment offgassing in spacecraft. The performance of the filter was measured in dry and humid atmospheres. A known concentration of DCM was passed through the adsorbent at a known flow rate. The adsorbent removed dichloromethane until it reached the breakthrough volume. Carbosieve SIII exposed to dry atmospheric conditions adsorbed more DCM than when exposed to humid air. Carbosieve SIII is a useful thermally regenerated adsorbent for filtering DCM from spacecraft cabin air. However, in humid environments the gas passes through the filter sooner due to co-adsorption of additional water vapor from the atmosphere.

This work describes the microbiological assessment and materials compatibility of a silver-based biocide as an alternative to iodine for the Crew Exploration Vehicle (CEV) and future spacecraft potable water systems. In addition to physical and operational anti-microbial counter-measures, the prevention of microbial growth, biofilm formation, and microbiologically induced corrosion in water distribution and storage systems requires maintenance of a biologically-effective, residual biocide concentration in solution and on the wetted surfaces of the system. Because of the potential for biocide depletion in water distribution systems and the development of acquired biocide resistance within microbial populations, even sterile water with residual biocide may, over time, support the growth and/or proliferation of bacteria that pose a risk to crew health and environmental systems.

A lab-scale testbed for screening and characterizing the chemical specificity of commercial “off-the-shelf” (COTS) polymer adsorbents was built and tested. COTS polymer adsorbents are suitable candidates for future trace contaminant (TC) control technologies. Regenerable adsorbents could reduce overall TC control system mass and volume by minimizing the amounts of consumables to be resupplied and stored. However, the chemical specificity of these COTS adsorbents for non-methane volatile organic compounds (NMVOCs) (e.g., methanol, ethanol, dichloromethane, acetone, etc) commonly found in spacecraft is unknown. Furthermore, the effect of humidity on their filtering capacity is not well characterized. The testbed, composed of a humidifier, an incubator, and a gas generator, delivers NMVOC gas streams to conditioned sorbent tubes.

Commercial transport aircraft have adopted TCP/IP based onboard networking technology to integrate information interchange. This change along with the addition of a TCP/IP based air-ground data link will permit the aircraft network to establish links with ground networks and be integrated into the airline enterprise network. There are many challenging considerations when connecting a remote network to an enterprise network. These challenges are multiplied when that remote network is constantly in motion, both physically and in terms of its link to the ground network. An important consideration in any enterprise network is the element of security. AEEC has published ARINC Report 811: Commercial Aircraft Information Security Concepts of Operation and Process Framework [1] as a guide for the airlines as they consider how to deal with this new challenge.

Understanding the effects of dynamic thermal and vacuum regeneration on VOC desorption kinetics is needed for the development of regenerable trace contaminant control air revitalization systems. The effects of temperature and vacuum quality on the desorption kinetics of ethanol from Carbosieve SIII were examined using 1 hour regeneration cycles. The effect of vacuum quality on ethanol desorption was studied by exposing adsorption tubes loaded with ethanol to low pressures (1.0, 0.5, 0.3, and 0.12 atm) at various thermal regeneration temperatures (160, 100, 70, and 25 °C). At 1 atm of pressure, ethanol removal was found to increase from 2% at 25 °C, to 25% at 70 °C, to 55% at 100 °C, and to 77% at 160 °C. Decreasing the atmospheric pressure from 1 to 0.1 atm for 1 hr did not significantly enhance Carbosieve SIII regeneration at ambient temperatures (25 °C). However, heating the adsorbent at low pressures enhanced its regeneration.

This work deals with the modeling and analysis of both AC and DC bus voltage control in aerospace applications. The results of the analysis are presented along with system models, including a voltage-controlled current source (vccs) used as a DC Bus controller, a d,q-controlled, IGBT-based, SVPWM-switched, ac-to-dc active converter/rectifier (AR) used as a DC Bus controller, a 3-phase ac generator voltage regulator (VR) used as an AC Bus controller, a 3-phase uncontrolled ac generator followed by an SCR-controlled ac-to-dc converter, used as a DC Bus controller (single-controlled bus), and a 3-phase dynamically-controlled ac generator followed by an SCR-controlled ac-to-dc converter, used to provide both AC and DC Bus control (dual-controlled bus).

This paper discusses the problem of designing electric machines (EM) for advanced electric generators (AEG) used in aerospace more electric architecture (MEA) that would be applicable to aircraft, spacecraft, and military ground vehicles. The AEG's are analyzed using aspects of Six Sigma theory that relate to critical-to-quality (CTQ) subjects. Using this approach, weight, volume, reliability, efficiency, and cost (CTQs) are addressed to develop a balance among them, resulting in an optimized power generation system. The influence of the machine power conditioners and system considerations are also discussed. As a part of the machine evaluation process, speeds, bearings, complexities, rotor mechanical and thermal limitations, torque pulsations, currents, and power densities are also considered. A methodology for electric machine selection is demonstrated. Examples of high-speed, high-performance machine applications are shown.

A detailed study was conducted on nitrification using a bench top bioprocessor system proposed for water recycling of a urine-soap wastewater expected to be generated by crewmembers on International Space Station (ISS) or similar long-term space missions. The bioprocessor system consisted of two packed bed biofilm reactors; one anoxic reactor used for denitrification and one aerobic reactor used for nitrification. lnfluent wastewater was a mixture of dilute NASA whole body soap (2,300 mg/L) and urea (500 mg/L as organic nitrogen). During two months of steady-state operation, average chemical oxygen demand (COD) removal was greater than 95%, and average total nitrogen removal was 70%. We observed that high levels of nitrite consistently accumulated in the aerobic (nitrifying) reactor effluent, indicating incomplete nitrification as the typical end product of the reaction would be nitrate.

The efficiency and robustness of pilot-automation interaction is a function of the volume of memorized action sequences required to use the automation to perform mission tasks. This paper describes a model of pilot cognition for the evaluation of the cognitive usability of cockpit automation. Five common cockpit automation design errors are discussed with examples.

Demand on the reliability of Electric Generators for Aerospace applications is assuming more importance everyday with the advent of “Fly-by-Wire” and “More-Electric-Aircraft” concepts. With today's high-powered avionics and sophisticated control systems, airline operators expect better performance and would no longer accept weak links in the system that need frequent maintenance. One of the weakest points in an electric generator is its reliance on rolling element bearings, which are subject to unpredictable and frequent failures. Huge redundancy and frequent maintenance ensure uninterrupted supply of electricity in an aircraft.

The bleed air contamination monitor was developed at Honeywell to ensure that our products provide the highest quality bleed air to aircraft environmental control systems. The bleed air contamination monitor is currently for ground based applications only. It is being developed into an on board system for future applications. Current Aircraft Cabin Air Quality measurement techniques are very labor intensive and require days or even weeks of laboratory analysis to provide results. This is unacceptable from a manufacturing and service perspective. Development of a real time analyzer began in the early 1990s and has progressed to a point where a product is ready for introduction that not only provides real time information regarding engine air contamination, but is also easy for operators to use with a minimum amount of training.

The issues of active vs. passive means of power quality improvement in aerospace applications are addressed. The concept of nonlinear load, i.e., the relationship between the current harmonics and system power factor has been reviewed. Both passive and active means of harmonic minimization are discussed, including resonance issues associated with passive networks and presenting an active rectifier switched in a Space Vector (SV) Pulse Width Modulation (PWM) manner. The analysis of power quality in aerospace applications is presented, together with the industry governing standards. Results of case studies are given, using Saber hierarchical tools for the system analysis. Both simulation and experimental results are provided, demonstrating power quality improvements in several aerospace applications.

In this work we have proposed an interesting clamping solution of V-band which has an important industrial impact by reducing the cost and assembly process as well compare to the traditional V-band. The design what we are focusing for is applied for all size of turbochargers which helps to connect the hot components such as manifold and turbine housing. The cost for V-band is mainly from T-bolt. It is made from special stainless steel which represents 50% of the total cost. In this work it is proposed a new V-band joint by changing bolt clamping status from tension to compression. From tension to compression we change the bolt material from high cost steel to low cost steel. The new total cost is reduced by 40%. The prototype is made and performed in static tests including anti-rotating torque test and salt spray test. The new joint meets the design requirements at static condition. Further work will focus on the dynamic qualification and at high temperature as well.