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A number of specimen life performance tests were conducted on three test lubricants selected to demonstrate their gross ranking capabilities. The results indicated that the test rigs should be used only for gross ranking. A large difference in magnitude of life values were obtained even though agreement in gross ranking was obtained by three out of the five participating laboratories. Further testing is recommended under preselected test conditions and lubricants.

Nickel-5 Aluminum (95 % Nickel-5 % Aluminum) is widely used in the aircraft engine industry. The excellent adhesive and cohesive strength of the coating, oxidation resistance and machinability make it an ideal material as both a bond coat for subsequent topcoats and as a build up material for dimensional restoration of worn or mismachined components. Plasma spraying has traditionally been the thermal spray process used to apply nickel aluminum, and the technical properties and performance characteristics are well documented. More recently, wire arc sprayed nickel aluminum is becoming widely used as an alternative to plasma spraying due to higher bond strengths, reproducibility, better machinability and more favorable economics. This paper presents the results of a testing program designed to compare the technical properties of arc sprayed versus plasma sprayed Nickel-5 Aluminum coatings.

The Shuttle orbiter currently uses hydrazine-powered APU’s for powering its hydraulic system pumps. To enhance vehicle safety and reliability, NASA is pursuing an APU upgrade where the hydrazine-powered turbine is replaced by an electric motor pump and battery power supply. This EAPU (Electric APU) upgrade presents several thermal control challenges, most notably the new requirement for moderate temperature control of high-power electronics at 132 °F (55.6 °C). This paper describes how the existing Water Spray Boiler (WSB), which currently cools the hydraulic fluid and APU lubrication oil, is being modified to provide EAPU thermal management.

An important current engineering problem in the aviation field involves the providing of increasingly effective lubricating oil filtration for today's more advanced aircraft engines. The critical demands of the higher powered reciprocating engines and the new gas turbine engines, together with the strong desire to reduce aircraft operating and maintenance costs require considerable refinement and improvement in oil filtration methods. This paper discusses some recent developments in scavenge oil filtration and describes a basic, new filter design.

The BSTCA (Battery Section Thermal Control Assembly) is a module of the Columbus MTFF (Man Tended Free Flyer). Electrical power required during eclipse periods, is made available from six nickel hydrogen batteries. A sophisticated multi-radiator configuration, with a hybrid heat pipe network, has evolved. Autonomous control of the assembly heat rejection capability has been achieved by a integrated network of LTHP's (Liquid Trap Heat Pipes) and CCHP's (Constant Conductance Heat Pipes) under the control of a conventional HCU (Heater Control Unit). The process of design selection and verification is discussed, for the BSTCA, with a detailed LTHP component presentation.

This paper is a review of the literature covering the history of the use of lubricants. The uses of oils derived from animals, vegetables and minerals are placed in perspective from ancient times to the Wright Brothers' flight in 1903. After that period, the discussion is confined largely to the lubrication of aircraft piston engines. The paper attempts to explain the preference for castor oil in European and British engines and the more general, but by no means exclusive, use of petroleum-based mineral oils in the United States. The British Air Ministry, in 1929, reached a decision to abandon castor oil due to availability and cost of petroleum-based oils. The simultaneous U.S. Army Air Corps recognition of the advantages of the very flat viscosity-temperature curve of Pennsylvania oils for hot running engines and for cold starting led to the world-wide use of these lubricating oils.

Yardney Technical Products is developing a high energy density Li-ion cell tailored for NASA's Extravehicular Mobility Unit battery. The goal of the program is to develop a Li-ion technology which offers long storage and cycle life in a system which provides energy density and exercise performance comparable to the current 6.7kg Zn-AgO battery. The Zinc-Silver Oxide cells which are most commonly used in this application provide 400 Wh/l with a 32 cycle life at 26.6Ah and 1.55V with a rated wet life of 425 days. To improve the energy density of the Li-ion cells we have focused on improving the energy density of its components. In addition to using thin metal foil current collectors, the energy density of the cathode material was improved by utilizing a high capacity Co doped nickel oxide material. Further efforts have focused on developing a more energy dense carbonaceous anode material. The results of this effort are reviewed.

Specifications describing performance characteristics for lubricating oils are examined. The author describes the engine performance requirements, and physical and chemical tests required by the military and by the leading automobile manufacturers. Specifications for passenger car automatic transmission fluids are also examined, as are synthetic aircraft lubricants for commercial and military use.

Laboratory, component, and engine tests have been conducted by the General Electric Co. to evaluate the various lubricant properties important to the J79 jet engine. Such properties as elastomer volume swell, oxidation-corrosion, coking characteristics, and lubricity were evaluated. The effects of these various properties on engine performance and how the laboratory results relate to the component results and engine test results are discussed.

Mathematical modeling of the Ni-H2 cell based on the fundamental electrochemical processes is necessary for accurately simulating the battery behavior on Space Station Freedom. Accurate predictions are incorporated as part of the development of the Space Station Electric Power System simulation. This simulation will be used to develop and test control algorithms which will maximize the available power in the most efficient way. This is a deviation from the approach used on smaller satellite power systems which are designed with substantial margin. Hence, the use of an empirical battery model is not feasible due to its low fidelity. This paper covers the electrochemical theory related to the Ni-H2 cells, and the analysis of experimental data used to develop relations between the cell state of charge and certain cell properties. Theoretical results are compared against well-documented experimental data.

The purpose of this SAE Aerospace Information Report (AIR) is to present a quantitative approach for evaluating the performance and capabilities of an Engine Monitoring System (EMS). The value of such a methodology is in providing a systematic means to accomplish the following: 1 Determine the impact of an EMS on key engine supportability indices such as Fault Detection Rate, Fault Isolation Rate, Mean Time to Diagnose, In-flight Shutdowns (IFSD), Mission Aborts, and Unscheduled Engine Removals (UERs). 2 Facilitate trade studies during the design process in order to compare performance versus cost for various EMS design strategies, and 3 Define a “common language” for specifying EMS requirements and the design features of an EMS in order to reduce ambiguity and, therefore, enhance consistency between specification and implementation.

The purpose of this SAE Aerospace Information Report (AIR) is to present a quantitative approach for evaluating the performance and capabilities of an Engine Monitoring System (EMS).

Lubricants used in space mechanisms must be thoroughly tested prior to their selection for critical applications. Traditionally, two types of tests have been used: accelerated and full-scale. Accelerated tests are rapid, economical, and provide useful information for gross screening of candidate lubricants. Although full-scale tests are more believable because they mimic actual spacecraft conditions, they are expensive and time consuming. The spiral orbit tribometer compromises between the two extremes. It rapidly determines the rate of tribochemically induced lubricant consumption, which leads to finite test times, under realistic rolling/pivoting conditions that occur in angular contact bearings.

A patented, in-tank, four-in-one system pumps, filters, agitates, and carbon treats airline/aerospace metal finishing solutions while eliminating the possibility of dangerous and costly leaks and spills. Excellent field performance has been reported for electroless nickel, hard chromium, cadmium, sulfamate nickel, and many other solutions for plating and electroforming. The portable, lightweight, preassembled systems consume no floorspace, provide from 1 to 3,000 gallons of filtered solution per hour, and are often employed with a reusable filter media to reduce the costs associated with filter cartridge consumption and disposal.

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.

The new type of fluid device described in this paper is closely analogous to a vacuum tube cathode follower amplifier. It provides an output pressure equal to an input control pressure, but with a high input impedance and low output impedance providing a power gain. A string of balls moving in response to pressures acting on the ball surfaces provides the basic valve action. Because of its structure and the use of balls as the control elements, this device is relatively easy to manufacture, does not require a lubricating fluid and can be operated at high temperatures.

The Naval Research Laboratory (NRL) and Johnson Controls Inc. (JCI) have joined together in a cooperative research and development effort to “space qualify” the JCI Common Pressure Vessel (CPV) Nickel Hydrogen (NiH2) battery. JCI is providing two (2) NiH2 batteries to NRL. One is for qualification tests and the second is for the flight experiment. NRL is responsible for the design, test and integration of the battery with an existing spacecraft electrical power system, launch of the battery with the host spacecraft, and providing data from the flight experiment. Since the intent of the experiment is to “space qualify” the JCI NiH2 CPV design, the battery will be “on-line” and fully charged during the launch of the host spacecraft. This paper will describe the NRL-JCI Cooperative Research and Development Agreement, the NiH2 CPV battery experiment design, and the qualification test program.

A method is described for the rapid solid state diffusion bonding of sheet metal structures fabricated from refractory metals or dispersion hardened metals such as TD nickel. This process avoids problems associated with welding or high-temperature brazing where overheating or fusion degrade or destroy mechanical properties of the base metals. Lap joints and T joints are made by this process in about 10 sec through the application of pressure and heat while the work piece is contained in a protective atmosphere. Joints thus produced are bonded over the entire faying surface and can be effectively coated for oxidation protection.

The electroplating anode completes the electrical circuit, distributes current to the parts being plated and influences metal distribution at the cathode. In addition, metal from a soluble anode may be converted into ions which enter solution and replenish those discharged at the cathode. There are important plating processes, however, that operate with insoluble anodes where the metal ion concentration in solution is controlled by the addition of soluble metal salts. Auxiliary and bi-polar anodes are used in conjunction with the primary anodes to improve coating thickness uniformity at the cathode. The influence of composition on anode behavior is illustrated by a review of the development of nickel anode materials. A subject of growing importance because of the associated disposal problems is the metal build-up that occurs when anode efficiency exceeds cathode efficiency. Complete automation of anode basket-loading operations may be possible.

There has been a recent upsurge in interest from the media concerning the quality of the environment within aircraft cabins and cockpits especially in the commercial world1-4. This has included (although by no means been limited to) the air quality, with particular reference to the alleged effects of contamination from the aircraft turbine lubricant. Possible exposure to ‘organophosphates’ (OPs) from the oil has raised special concerns from cabin crew. Such is the concern that government organisations around the world, including Australia, USA and UK, have set up committees to investigate the cabin air quality issue. Concern was also voiced in the aviation lubricants world at the way in which OP additives in turbine lubricants were being blamed in some reports for the symptoms being experienced by air crew and passengers. SAE Committee E-34 therefore decided that it should gather as much available information on the subject as possible.