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A 500 hours endurance test was performed with a heavy-duty engine (Euro IV); MAN type D 0836 LFL 51 equipped with a PM-Kat®. As fuel 100% biodiesel was used that met the European specification EN 14214. The 500 hours endurance test included both the European stationary and transient cycle (ESC and ETC) as well as longer stationary phases. During the test, regulated emissions (carbon monoxide, nitrogen oxides, hydrocarbons and particulate matter), the particle number distribution and the aldehydes emission were continuously measured. For comparison, tests with fossil diesel fuel were performed before and after the endurance test. During the endurance test, the engine was failure-free for 500 hours with the biogenic fuel. There were almost no differences in specific fuel consumption during the test, but the average exhaust gas temperature increased by about 15°C over the time. Emissions changed only slightly during the test.

A joint venture called Aviation Partners Boeing successfully integrated winglets into the Next-Generation 737–800 by retaining performance improvements with minimal weight penalty on the existing 737 wing design. Program challenges included developing both retrofit and production configurations using a common winglet design, causing minimal impact on all customers, and causing minimal disruption to the 737 production process. Winglet benefits along with improved performance include reduced engine wear and enhanced visual appeal.

A hydrogen economy is an increasingly popular solution to lower global carbon dioxide emissions. Previous research has been focused on the economic conditions necessary for hydrogen to be cost competitive, which tends to neglect the effectiveness of greenhouse gas mitigation for the very solutions proposed. The holistic carbon footprint assessment of hydrogen production, distribution, and utilization methods, otherwise known as “well-to-wheels” carbon intensity, is critical to ensure the new hydrogen strategies proposed are effective in reducing global carbon emissions. When looking at these total carbon intensities, however, there is no single clear consensus regarding the pathway forward. When comparing the two fundamental technologies of steam methane reforming and electrolysis, there are different scenarios where either technology has a “greener” outcome.

An automated drilling and fastening system is under development at the GEMCOR Engineering Corporation for wing manufacture on a new commercial airframe program. It is the first time that cold-working and hole inspection have been integrated into an automated fastener installation system. Numerical control and monitoring of all process parameters have been integrated in the system to achieve the greatest degree of accuracy and repeatability in fastener installation and to provide real-time, in-process statistical quality control. An integral component of the system is a capacitance probe used to measure the diameter and profile of drilled holes. Measurement information obtained with the hole probe is used to monitor the drilling process and predict tooling wear. This paper briefly discusses fastener hole requirements and the effects of hole quality on fatigue life. An overview of the capacitance measurement technique is also presented.

In this paper, we address the thermal management issues which limit the lifespan, specific power and overall efficiency of an air-cooled rotary Wankel engine used in Unmanned Air Vehicles (UAVs). Our goal is to eliminate the hot spots and reduce the temperature gradients in the engine housing and side plates by aggressive heat spreading using heat pipes. We demonstrate by simulation that, for a specific power requirement, with heat spreading and more effective heat dissipation, thermal stress and distortion can be significantly reduced, even with air cooling. The maximum temperature drop was substantial, from 231°C to 129°C. The temperature difference (measure of temperature uniformity) decreased by 8.8 times (from 159°C to 18°C) for a typical UAV engine. Our heat spreaders would not change the frontal area of the engine and should have a negligible impact on the installed weight of the propulsion assembly.

Heat pipes, loop heat pipes and capillary pumped loops are heat transfer devices driven by capillary forces with high-effectiveness & performance, offering high-reliability & flexibility in varying g-environments. They are suitable for spacecraft thermal control where the mass, volume, and power budgets are very limited. The Canadian Space Agency is developing loop heat pipe hardware aimed at understanding the thermal performance of two-phase heat transfer devices and in developing numerical simulation techniques using thermo-hydraulic mathematical models, to enable development of novel thermal control technologies. This loop heat pipe consists of a cylindrical evaporator, compensation chamber, condenser along with vapor and liquid lines, which can be easily assembled/disassembled for test purposes. This laboratory setup is especially designed to enable the visualization of fluid flow and phase change phenomena.

This paper characterizes the features and describes some of the benefits of the present generation of multigrade “MS” oils. Particular emphasis is placed upon viscosity retention characteristics as a function of the stability of the viscosity index improver. Comparative automobile field tests in private commuter, taxicab, and highway service are shown for both SAE 10W-30 and a carefully compounded SAE 10W-40 oil. Observations of cylinder and piston ring wear, crankcase deposits, PCV valve cleanliness, and oil economy are reported.

Bioregenerative systems for removal of gaseous contaminants are desired for long-term space missions to reduce the equivalent system mass of the air cleaning system. This paper describes an innovative design of a new biofiltration test lab for investigating the capability of biofiltration process for removal of ersatz multi-component gaseous streams representative of spacecraft contaminants released during long-term space travel. The lab setup allows a total of 24 bioreactors to receive identical inlet waste streams at stable contaminant concentrations via use of permeations ovens, needle valves, precision orifices, etc. A unique set of hardware including a Fourier Transform Infrared (FTIR) spectrometer, and a data acquisition and control system using LabVIEW™ software allows automatic, continuous, and real-time gas monitoring and data collection for the 24 bioreactors. This lab setup allows powerful factorial experimental design.

CONTINUOUS increase in the power output of aircraft engines introduces from time to time lubricating problems including excessive wear and scuffing, excessive oxidation of the oil, and ring sticking. The one problem of ring sticking was chosen and the discussion is limited to the testing of lubricating oils to compare their abilities to prevent this type of failure. Although the best answer as to the ring-sticking tendencies of a lubricant rests with the full-scale engine in service, a simple test is needed during the development period. The development work which led up to the selection of an L-head CFR engine for a ring-sticking test is discussed. Various criteria used for detecting incipient ring sticking are mentioned and a method for direct measurement of incipient ring sticking is described.

Airline aircraft maintenance and ground support services meet at the connection points for ground service. Ground power must be applied to the aircraft, but responsibility for the aircraft receptacle falls to aircraft maintenance. This responsibility gap is not currently being addressed by the industry. For years any difficulty in applying power to an aircraft on the ground has been blamed solely on the ground power cable or generator. Any potential problems with the receptacles was largely ignored by ground service personnel, since they are not allowed to touch the aircraft. No one thought to look closely at the receptacle as a potential source of the inability to reliably apply power to the aircraft (in fact, routine maintenance A,B,C or D maintenance did not routinely check or change the receptacle).

The U.S. general aviation manufacturing industry has deteriorated almost to the point of extinction within the past decade. There are several factors potentially contributing to this deterioration; however, the escalation and unpredictability of product-liability costs are claimed to be the most significant. General aviation manufacturers are subject to the product-liability laws of each state. Efforts to reform this system have been underway since 1986. However, these efforts have been stymied by opponents whose primary concern is that the reform will not allow some accident victims to be properly compensated for their damages. There are immediate policy alternatives that will potentially alleviate the product-liability problem of the industry: General Aviation Accident Liability Standards Act, Product Liability Fairness Act, and state reform. Other alternatives that require further investigation include increased safety regulation and mandatory pilot liability insurance.

Tyre wear is of significant concern for the automotive industry due to multiple reasons including vehicle performance, safety, economy, environmental (particulate matter emission) aspects, etc. Therefore, ensuring enhanced tyre tread wear resistance is one of the most important criteria while developing a new tyre. Tyre wear phenomenon is influenced by various factors, such as road conditions, driving habits, maintenance practices and tyre design parameters (construction, geometry and material). The wear assessment through the classical field-testing approach consumes significant time and resources. Therefore, digital predictive tools are very useful in predicting wear characteristics at the early stage of the tyre development process. In this study, an attempt has been made to capture the impact of tread geometry, tread material, vehicle geometry, vehicle speed, test track geometry, etc. on tyre wear.

Human performance deterioration in extreme conditions challenges the viability of critical scenarios during a space mission. Exposure to space flight environment, including microgravity appears to increase the stress on the sensory-motor controls regulatory system in the brain because it is calibrated to operate under gravity. Any pre-existing central dysfunction can allow an input overload which can cascade to and alter other related functions down the functional hierarchy, such as physical (fine postural control, coordination and dexterity, strength, reaction time, fatigue, space perception/orientation) cognitive(trajectory control, attention and vigilance, time awareness, decision making, concentration, and memory), and emotional (motivation, self-control, calmness/aggressiveness). This phenomenon has direct influence on an individual’s tendency for “error proneness”.

A pump concept was elaborated based on the COLUMBUS requirements. Mainly the requirements for long life and low-noise operation were taken into consideration in this design. According to the pump concept a model pump for operation in a thermal loop was built and tested with existing Industrial facilities. Tests revealed that this very compact and light pump fulfils already the hydraulic requirements completely and is near to the low-noise requirement. After a running time of 1000 hrs with the fluids water and liquid ammonia the ceramic bearings show no wear at all. The results allow to expect that this pump concept will fulfil the stringent COLUMBUS requirements.

The Sabatier reactor is an exothermic, heterogeneous catalytic reactor that has the function of reducing carbon dioxide to methane and water vapor. Sabatier reactor operation is affected by gravity through the effects of buoyant forces. The buoyant forces affect the transfer of heat and can be significant in determining the temperatures of the various portions of the reactor. The temperatures then affect the fundamental processes such as the chemical reaction rate. This paper presents the results of zero “G” computer model simulations of Sabatier reactor operation. Groundbase experiments were made for various manned loadings under normal ambient and gravity (l-G) conditions and were correlated with normal gravity simulations. The zero “G” simulations show the reactor will run significantly hotter in a zero “G” environment if cooling air flow is not increased to compensate for the loss of natural convections.

The kinetics of the Sabatier methanation reaction, the reduction of carbon dioxide with hydrogen to methane and water, was investigated for 58 percent nickel on kieselguhr catalyst and 20 percent ruthenium on alumina catalyst. Differential rate data from an experimental program were correlated with a power function rate equation both for forward and reverse reactions. The kinetic parameters of activation energy, frequency rate constant and reaction order were determined for the rate equation. The values of these parameters were obtained from an Arrhenius plot of the experimental differential rate data. Also the carbon monoxide side reaction effect was measured and included in the correlation of parameters. The reaction was found to fit the rate equation experimentally within the temperature range 421°K, where the reaction effectively begins, to 800°K where the reaction rate drops and departs from the rate equation form.

Obsolescence Material management plays an important and vital role in today’s modern Aerospace manufacturing, Aerospace Maintenance, Repair and Overhaul industry as well as Aerospace Distributors. Aerospace vehicles have a considerable longer product life-cycle when compared to any other consumer goods like automobile and electronics industry. With the advent of new, disruptive technologies, many sources and supplies of materials including COTS and Standard catalogue parts, components and goods, which are widely used in an Aerospace manufacturing environment, are diminishing at a considerable rate and thus result in their obsolescence before the end disposal of the product life cycle. It is one of the leading causes to the sale of counterfeit and fraudulent parts and components, which can result in considerable deterioration of Quality and Cost to Customer.

The feasibility of a near-complete and biosafe conversion of human- and food waste into biogas was investigated in the context of ESA’s MELiSSA loop (Micro Ecological Life Support System Alternative). The treatment comprises of a series of processes, i.e. a mesophilic lab-scale CSTR (continuously stirred tank reactor), an upflow biofilm reactor, a fibre liquefaction reactor containing the rumen bacterium Fibrobacter succinogenes and a hydrothermolysis system in near-critical water. In the one-stage CSTR, a biogas yield of 75% with a specific biogas production of 0.37 L biogas g-1 added VS (volatile suspended solids) at a HRT (hydraulic retention time) of 15 to 25 days was obtained. When the SRT (solid retention time) was uncoupled from the HRT, and all solids were completely retained in the methane reactor, a more complete biogas conversion was observed at a SRT of above 20 days, corresponding to a 10% increase of degradation on a total COD basis.

After the launch to the ISS (International Space Station) with The Space Shuttle flight STS 118 13A.1 on August 9th 2007 and the accommodation in the US lab Destiny, the air quality monitor ANITA (Analysing Interferometer for Ambient Air) has been successfully put into operation. ANITA is a technology demonstrator flight experiment being able to continuously monitor with high time resolution the air conditions within the crewed cabins of the ISS. The system has its origin in a long term ESA technology development programme. The ANITA mission itself is an ESA-NASA cooperative project. ESA is responsible for the provision of the HW, the data acquisition and data evaluation. NASA's responsibilities are launch, accommodation in the US Lab Destiny, operation and data download. The ANITA air analyser is currently calibrated to detect and quantify online and with high time resolution 33 gases simultaneously with down to sub-ppm detection limits.