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This specification covers quality assurance sampling and testing procedures used to determine conformance to applicable material specifications of corrosion- and heat-resistant steel and alloy forgings.

Most of current jet aircraft circulate fuel on the airframe to match heat loads with available heat sink. The demands for thermal management in wide range of air vehicle systems are growing rapidly along with the increased mission power, vehicle survivability, flight speeds, and so on. With improved aircraft performance and growth of heat load created by Aircraft Mounted Accessory Drive (AMAD) system and hydraulic system, effectively removing the large amount of heat load on the aircraft is gaining crucial importance. Fuel is becoming heat transfer fluid of choice for aircraft thermal management since it offers improved heat transfer characteristics and offers fewer system penalties than air. In the scope of this paper, an AMESim model is built which includes airframe fuel and hydraulic systems with AMAD gearbox of a jet trainer aircraft. The integrated model will be evaluated for thermal performance.

Aircraft potable (drinking) water systems haven’t changed significantly in the last half-century. These systems consist of cylindrical water tanks pressurized by bleed air from the jet engines, with insulated stainless steel distribution lines. What has changed recently is the increase in the possibility of aircraft picking up contaminated drinking water at foreign and domestic stops. Customer awareness of these problems has also changed - to the point where having reliable drinking water is now a competitive issue among airlines. Old style potable water systems that are used on modern aircraft are high maintenance and exacerbate the growth of microbes because the water is static much of the time. The integrity of some pressurized water tanks are also a concern after years of use. Cost-effective mechanical and biological solutions exist that can significantly reduce the amount of chemicals added and provide good potable water.

Coated refractory metals, coated and alloyed graphites, hafnium-tantalum alloys, refractory borides, and stabilized zirconias are considered for the 3600–4000 F high-velocity air environment. Only refractory borides and stabilized zirconias are indicated as offering long duration and reuse capabilities for such high-temperature utilization. Iridium, as coatings on substrates of either graphites or refractory metals, appears attractive for shorter times (less than 1 hr). Environmental evaluation and the need for a theoretical framework to enable the prediction of performance data for such materials are indicated to be major problems facing users and suppliers.

This paper discusses five different methods for measuring the gas stream temperature from a burner using a hydrocarbon fuel, air, and oxygen. Tests were made with a single shielded BeO probe, a bare wire iridium -- 60% rhodium/iridium couple, a tantalum triple shielded platinum -- 10% rhodium/platinum thermocouple, the sodium line reversed technique, and a watercooled total enthalpy probe. The most serviceable system proved to be the bare wire iridium -- 60% rhodium/iridium couple, particularly for carrying out stream surveys where relative, rather than true temperatures, are of primary concern. More study is needed to establish a system for determining the true stream temperature.

As a part of a program jointly supported by the USAF and Canada's Department of National Defense, BlueStar is developing large (50 to 100-Ah)lithium ion cells for aircraft and spacecraft applications. Presently, 20-Ah cells are being developed as the first stage of the scale-up process and the design of these cells involves several tradeoffs related to the specific nature of this application. This paper will present the design of this first generation cell in the context of these tradeoffs as well as presenting the results of the performance and life testing of these cells.

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.

Shortly after World War II, as aircraft became more sophisticated and power-assist, flight-control functions became a requirement, hydraulic system operating pressures rose from the 1000 psi level to the 3000 psi level found on most aircraft today. Since then, 4000 psi systems have been developed for the U.S. Air Force XB-70 and B-1 bombers and a number of European aircraft including the tornado multirole combat aircraft and the Concorde supersonic transport. The V-22 Osprey incorporates a 5000 psi hydraulic system. The power levels of military aircraft hydraulic systems have continued to rise. This is primarily due to higher aerodynamic loading, combined with the increased hydraulic functions and operations of each new aircraft. At the same time, aircraft structures and wings have been getting smaller and thinner as mission requirements expand. Thus, internal physical space available for plumbing and components continues to decrease.

Shortly after World War II, as aircraft became more sophisticated and power-assist, flight-control functions became a requirement, hydraulic system operating pressures rose from the 1000 psi level to the 3000 psi level found on most aircraft today. Since then, 4000 psi systems have been developed for the U.S. Air Force XB-70 and B-1 bombers and a number of European aircraft including the tornado multirole combat aircraft and the Concorde supersonic transport. The V-22 Osprey incorporates a 5000 psi hydraulic system. The power levels of military aircraft hydraulic systems have continued to rise. This is primarily due to higher aerodynamic loading, combined with the increased hydraulic functions and operations of each new aircraft. At the same time, aircraft structures and wings have been getting smaller and thinner as mission requirements expand. Thus, internal physical space available for plumbing and components continues to decrease.

The 912 engine is a well known 4-cylinder horizontally opposed 4-stroke liquid-/air-cooled aircraft engine. The 912 family has a strong track record: 40 000 engines sold / 25 000 still in operation / 5 million flight hours annually. 88% of all light aircraft OEMs use Rotax engines. The 912iS is an evolution of the Rotax 912ULS carbureted engine. The “i” stands for electronic fuel injection which has been developed according to flight standards, providing a better fuel efficiency over the current 912ULS of more than 20% and in a range of 38% to 70% compared to other competitive engines in the light sport, ultra-light aircraft and the general aviation industry. BRP engineers have incorporated several technology enhancements. The fully redundant digital Engine Control Unit (ECU) offers a computer based electronic diagnostic system which makes it easier to diagnose and service the engine.

This paper discusses various engine installations in Naval aircraft, looking especially at their costs of maintenance. Fuel systems, fuel control systems, and several engine accessories are discussed for present and future engines. It is concluded that simple, reliable equipment is necessary to keep aircraft in the air instead of in maintenance areas on the ground.

A short survey of wing tip geometries for drag reduction is presented. These devices have been divided into two broad categories of passive and active. The first category is made of fixed geometries, while the second group is made of those employing moving parts. The former group is further divided into planar and nonplanar designs. In every case, a brief explanation of the underlying logic is given. Altogether, more than fifteen completely different designs and over seventy references have been cited. Some of these designs, such as winglets, have been explored for many years and have proven to be very effective at reducing the induced drag at higher values of lift coefficient. Some others, such as wing tip turbines, have just begun to attract attention. Wing tip fuel tanks, not being solely employed for drag reduction, have not been included in this paper.

A series calculation methodology from the injector nozzle internal flow to the fuel spray was applied to investigate the internal flow and spray of a nozzle whose orifices distributed in different space layers. The nozzle internal flow calculation using an Eulerian three-fluid model and a cavitation model was performed. The needle valve movement during the injection period was taken into account in this calculation. The transient data of spatial distributions of velocity, turbulent kinetic energy, dissipation rate, void fraction rate, etc. at the nozzle exit were extracted. These output data were transferred to the spray calculation, in which a primary break-up model was applied to the Discrete Droplet Model (DDM). The calculation results were compared with the results of the measurement data of spray. Predicted spray morphology and penetration showed good agreement with the experiental data.

A new family of canister-type fuel pumps for use on both rotary and fixed-wing aircraft in general aviation use will be described. The pump, which features a wet-brush DC motor, offers advantages on aircraft where ease of maintenance and minimum downtime is very important. Major features of the new design, pump performance, and maintenance cost savings will be discussed.

This paper documents the design and validation of a closed cycle propulsion system suitable for use on the Perseus A high altitude research aircraft. The atmospheric science community is expected to be the primary user of this aircraft with initial missions devoted to the study of ozone depletion and global warming. To date large amounts of funding are not available to the atmospheric science community, so to be useful, the aircraft must satisfy stringent cost and performance criteria. Among these, the aircraft has to be capable of carrying 50 kg of payload to altitudes of at least 25km, have a initial cost in the $1-2M range, be capable of launch from remote sites, and be available no later than 1994. These operational criteria set narrow boundaries for propulsion system cost, complexity, availability, reliability, and logistical support requirements.

A unique heat exchanger has been developed with potential applications for cooling high power density electronics and perhaps high energy laser mirrors. The device was designed to absorb heat fluxes of approximately 50 w/cm2 (158,000 Btu/hr.ft2) with a low thermal resistance, a high surface temperature uniformity and very low hydraulic pumping power. A stack of thin copper orifice plates and spacers was bonded together and arranged to provide liquid jet impingement heat transfer on successive plates. This configuration resulted in effective heat transfer coefficients, based on the prime surface, of about 85,000 w/m2 °C (15,000 Btu/hr.ft2 °F) and 1.8 watts (.002 HP) hydraulic power with liquid Freon 11 as coolant.

Eight fixed-wing reusable horizontal landing booster point design concepts are presented and compared on the basis of weight, cost, technical difficulty, and availability date. The eight vehicle types considered are all basically two-stage systems with a lifting body reusable second stage, with all vehicles normalized to place 40,000 lbs. payload in orbit. All flight vehicles are fully recoverable and capable of flying back and landing at the launch site. Vehicle types discussed are vertical take-off horizontal landing rockets, sled launched horizontal take-off rockets, runway launched horizontal take-off rockets, air breathing first stages, combined air breathing and rocket first stages, oxidizer collection concepts, supersonic combustion ramjets, and in-flight refueling vehicles. Each of these vehicle types is depicted in the paper and its design and performance characteristics are discussed.

A comparison of various numerical tools and techniques was performed for calculating the lightning indirect effects to composite structures and internal systems. This paper is a summary of the initial comparison results. Detailed results of each technique considered are given in additional separate papers presented during this conference. The modeling considered current distributions over and within composite surfaces and the coupling of current and voltages to internal systems such as wire bundle cables and hydraulic and fuel tubes. The models were compared to each other and to measured data from low level swept continuous wave (LLCW) tests performed on two test fixtures. Other features of the codes such as run time, ease of use, computer requirements, availability of documentation and technical support, etc. are compared as well.

Wheat plants were grown at water potentials in the root zone of -0.4, -3.0, and -5.0 kPa in root modules with various porous membranes through which the nutrient solution was delivered. Root modules contained plants grown during 49 days on different types of porous membranes: ceramic porous tubes with diameters of 10 mm or 22 mm, a porous titanium plate, in a compartment with a porous ceramic tube in perlite and in a 2.5 cm layer of perlite which covered a porous titanium plate. Root modules containing perlite showed much higher dry mass plants in yield than plants in root modules without perlite. A drop in water potential resulted in growth inhibition in all of the modules, especially in the tests without perlite. Design characteristics of the modules significantly affected the root distribution volume. These results may provide additional information in the design of root modules for future space plant growth chambers.