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Through a market analysis, PETROBRAS identified an opportunity to launch a new product dedicated to diesel boats market. This paper describes the activities performed by PETROBRAS research center (CENPES) during the new diesel development: new or improved methodologies to ensure reliable comparative performance, fuel consumption and smoke emissions analysis, with appropriate precision to elucidate differences between the new fuel and the conventional marine diesel. Performance tests were conducted by using radar monitoring. For fuel consumption, constant engine speed tests were made, with fuel flow measurement and acquisition. Smoke tests were performed using a total flow smokemeter, installed directly on the exhaust gas pipe. Results showed that, because of its special characteristics, the new diesel allows performance gains up to 6% and smoke emissions reduction up to 83%. Fuel consumption remains in the same level of regular marine diesel.

In spite of the apparent simplicity of marine propellers, their selection for small craft is complicated because of the possible interactions of numerous pertinent variables. It is not the intent of this paper to discuss propeller design, but rather to present procedures for selecting the most efficient propeller commercially available. A secondary objective is to point out the importance of gear reduction and its effect on propeller efficiency. To achieve these objectives, this paper will discuss those variables which must be considered in determining propeller dimensions and the modifications of these dimensions necessary for satisfactory performance under cavitating conditions.

As a designer and licensor of both two-stroke crosshead and medium speed trunk piston diesel engines, MAN B&W offers the industry engines in the power range from approx. 600 HP up to some 64,000 HP per unit. Whereas the four-stroke engine programme embodies engines with power outputs of up to some 19,000 HP per unit, the two-stroke programme starts at approx. 2000 HP per unit giving a considerable overlap in the medium power range so as to enhance the application possibilities. Over the years the distribution on two-stroke and four-stroke engine production has been fairly constant, whether counted as a whole or for MAN B&W engines only. This paper will, in particular, discuss the ongoing development and application potential of the MC-range of two-stroke engines which were introduced in 1982, and which have proved to be our Company's most successful engine programme so far, both in respect to engine sales and actual experience.

In the last four of the past twenty-eight year history of marine propulsion gas turbine engines, their numbers have doubled. Specific types of gas turbine engines in certain areas of compatibility with both military and commercial vessel power plant design have become recognized as being well beyond the prototype stage. The appearance of the establishment of some application trends and niches is described and rationalized from the technical and historical/statistical viewpoints. Demonstrated Engineering, Economic and Operational advantages are presented with emphasis in the large commercial marine services.

It is the responsibility of the boating industry to make certain that its marine products are designed and manufactured to operate safely and under almost all conceivable conditions. It is also the industry's responsibility to educate boat operators and the general public in common sense boating practices. However, in attempting to improve boating's safety record, it must be remembered that in the final analysis if the boat operator does not use good judgment or comply with the law, then all the engineering improvements, educational programs, and efficient law enforcement will not prevent boating accidents.

Mariner 6 and Mariner 7 successfully completed every one of the missions' science and engineering objectives during their average 219, 000, 000 mile trip to and close fly-by of the planet Mars in 1969. Man's knowledge of the “red planet” has greatly increased with the Television, Infrared Spectrometer, Ultraviolet Spectrometer, Occultation and Celestrial mechanics data returned by both Mariners. The Mariner '69 was based on a design of its predecessors, had incorporated a significant increase in flexibility that made it much more difficult to test, but yet afforded the opportunity to overcome many problems in the ground test program and compensate for all problems experienced during flight. The Test and Operations Program experienced serious problems at the start, throughout, and during the final week of launch preparations.

The Mariner V mission to and past the planet Venus in 1967 is described and some scientific results are summarized. The engineering challenge and process of physically converting a machine designed to conduct a Mars flyby into one suitable for the Venus mission are discussed, and particular technical problems and solutions arising from this conversion or other aspects of the 1967 flight mission are examined. Finally, some results of a study of test effectiveness in this project are considered.

Use of ground effect to provide an effectively infinite aspect ratio to an aerodynamically designed surface effect ship is explained, and integration of improved translational characteristics with GEM jet hovering is discussed. A suspension system for the ship's economical operation over wave surfaces is outlined, and results of test craft aspects of the 100 ton ship are presented. The economic potential of surface effect ships, their possible use as cargo and passenger carriers, and their value as a stimulus to American maritime trade are pointed out. The history of the present program of research and development is also reviewed.

The Royal Navy now deploys helicopters in all its escorts. The pattern and concept of operations from small ships have evolved over the years and detailed study of the control, landing, and deck handling of the helicopter have affected both ship and aircraft design. Similarly, a maintenance and support organization has grown out of the need to supervise the activities of over 40 separate embarked units.

Among the factors attributable to Ford's success at Le Mans, France in 1966 is the high efficiency air induction system of the 427 GT engine. Contrary to the basic design parameters of passenger car engine induction systems, which consider part-throttle transitions and fuel economy, induction systems for high speed, high-output competitive engines are quite the opposite. These engines demand maximum airflow capacity, and equal balance of air/fuel mixture to each cylinder to insure high efficiency throughout the engine speed range under full-throttle conditions. Recognition of this need, its resolution, and the application of resultant techniques to the Ford 427 engine since its inception in 1963, are the basis for this paper. The GT induction system is the product of a new development technique that involved the extended use of an induction flow-stand, as well as extensive studies of various types of manifolds and cylinder heads.

The design and development of Mark II GT brake system within the parameters dictated by the Mark I chassis presented many problems. The Mark II GT with its larger 427 cubic inch engine had more weight and much higher performance than the Mark I. Space limitations of the carryover wheels and suspension imposed a severe handicap on individual brake component design. This was compounded by shortening the normal one year development time to a three month period. Part I of this paper is devoted to the consideration of factors which control the design of a brake. The concept of kinetic energy and its effects on brake performance is reviewed briefly. Use of the ventilated rotor design is explained for applications where severe heat is a problem, as in the case of the Mark II GT. The development of the brake system from the 24 hour Daytona endurance race to the Le Mans Grand Prix race is reviewed.

A preliminary assessment of the reach envelope and field of vision (FOV) for a subject wearing a Mark III space suit was requested for use in human-machine interface design of the Science Crew Operations and Utility Testbed (SCOUT) vehicle. The reach and view of two suited and unsuited subjects were evaluated while seated in the vehicle using 3-dimensional position data collected during a series of reaching motions. Data was interpolated and displayed in orthogonal views and cross-sections. Compared with unsuited conditions, medio-lateral reach was not strongly affected by the Mark III suit, whereas vertical and antero-posterior reach were inhibited by the suit. Lateral FOV was reduced by approximately 40° in the suit. The techniques used in this case study may prove useful in human-machine interface design by providing a new means of developing and displaying reach envelopes.

In recent years, the design and development of combustion engines have been revolutionized by the use of computer simulation tools. These tools allow rapid dissemination of information about critical systems during the concept design phase, and also allow a high level of optimization within the total engine design process. The extended cooperation between manu-facturer and external engineering partner creates the necessity of a common access to the simulation tools for both parties. At FEV several simulation programs have been developed [1, 2] that are used by specialists who are familiar with the specific program. Due to the frequent use of these tools in various projects [3, 4] their database is always up to date, they are continuously improved and the results are verified by measurements. The simulation models for the dynamic calculations of valve train, as well as valve train drive systems, have been transferred to a commercially available multi-body-dynamic simulation software.

Inks periodically used to mark the inlet faces of prototype catalyst substrates before testing were analyzed by a variety of methods to identify and quantify inorganic atomic constituents. The dominant inorganic constituents in these inks were Al and Ti, which would likely be in the form of Al2O3 and TiO2 after ink application and firing in air, and thus relatively inert as these are often already constituents in many catalyst washcoats. However, potential catalyst poisons, such as S, Cl, Cr, Zn, and Na were also detected in some inks. A simple model was developed to quantify the possible impact of the potentially irreversible catalyst poisons (such as Si, Cl and Na) based on ink loading during application, constituent concentration in the ink, and catalyst active site density.

The commercial aviation maintenance industry has been changing rapidly for the past ten years. Declining demand and overcapacity, shifting market/financial forces, and issues of personnel training and technology have combined to drastically change the business of maintaining air transport fleets. This has placed great stress on existing maintenance organizations who must struggle to survive. This paper describes one approach which can be used by aviation overhaul and maintenance service providers to devise new growth and management strategies. The approach, known as Market Driven Maintenance, uses classic product marketing strategies to help aircraft maintenance centers adjust scheduling and marketing strategies to attract new and more profitable market segments.

Low-Speed Pre-ignition (LSPI) is an undesirable abnormal combustion phenomenon observed in turbocharged, direct-injection spark-ignition engines and is characterized by early heat release, high cylinder pressures and severe, potentially damaging knock. LSPI has been studied for more than a decade and engine design, operating conditions and fuel and engine oil formulations have all been identified as contributing factors. A significant focus on engine oil has led to the establishment of the Sequence IX engine test and the second-generation of GM dexos® oil requirements, as well as a convergence of engine oil detergent causality. Conclusions about the effects of fuel on LSPI have been more varied, but as part of a recently completed research consortium, the LSPI tendency of market fuels with a range of properties, including composition, boiling point distribution, ethanol content and particulate matter index (PMI) were evaluated.