Search Results

High resolution control torques may be applied to a space vehicle by means of angular momentum storage devices, such as the reaction wheel or sphere. The reaction sphere eliminates gyroscopic cross-coupling, bearing malfunctions, and friction effects inherent to reaction wheels, by suspending a spherical rotor within an electrostatic field and torquing by means of three orthgonal stators. The present sphere design produces a peak torque of 0.02 ft-lb and is capable of storing 0.5 ft-lb-sec angular momentum. The rotor is 5 in. in diameter and is suspended by four series self-resonant, high-voltage circuits. Heat is rejected from the rotor by radiation to the electrodes and conduction from the electrodes to the structure. Dimensional tolerances are maintained by simplifying the housing assembly to two hemispheres within which the electrodes and stators are machined.

The use of conventional torsional vibration measuring equipment on single cylinder engines in the below 2 hp range is discussed. Disadvantages of this measuring equipment are outlined. Since this equipment has low voltage output, it is especially susceptible to noise which may result from random electromagnetic fields, or random wave forms which result from normal cycle-to-cycle variations. An illustration of a new system is presented which eliminates these defects. This method utilizes a high voltage output signal and is composed of inexpensive mechanical-electrical stock parts and components.

This specification establishes the qualification and acceptance limits for aeronautical engine high tension spark igniters.

Rectified a-c systems are better, more reliable automotive power supply systems than the traditional d-c generators. Requirements today are for sealed bearings, slip ring and brush assemblies in sealed or dust-proof compartments, mounting interchangeability, and control units that prevent thermal runaway and high transient voltages. Three systems are discussed: a 40, 60, and a 100 amp system. Selection of a system should be based on an engineered analysis.

High-voltage electron beam welding is discussed for a variety of aerospace applications. These include repair welding, welding of miniature electronic components, and welding of structural hardware. The specific procedure for each application is presented. Particular emphasis is placed on discussing the contribution of the characteristics of the process - low energy input, high-purity welding environment, and precise controllability - to the success of each application.

THE development of engines with higher compression ratios and those having valves in the head has meant that the minimum performance requirements of present-day distributor and coil type ignition systems are being approached. The authors of this paper have closely examined the ignition system as a whole to determine if these new demands can be met without appreciably increasing the primary current. The authors suggest that, if the reserve energy of ignition coils could be used more effectively, we could reduce its value and use the excess energy to charge the secondary circuit to a higher voltage without affecting total reliability.

These standards are written to cover internal combustion heat exchanger type heaters used in the following applications:

This standard covers two basic types of spark plugs as follows:

NAVAL architecture and aeronautics are compared to show what each has learned from the other. Design and performance of airplanes, seaplanes, flying boats, airships, hydroplanes, steamships, and sail boats are discussed as examples of this exchange of benefits, giving the relative advantages and disadvantages of each type. The outstanding performance record of the Graf Zeppelin is cited as proof that the airship is more suitable than is the airplane for long-range oceanic transport. Submerged hydrovanes for hydroplanes, seaplanes, and flying boats, with their advantages and disadvantages, are discussed at length. An aeronautical method of analysis is used to explain why some yachts are closer-winded than others with similar sails and rigging.

Ignition is discussed in a broad and non-technical way. The definition of the word ignition should be broad enough to include the complete functioning of the ignition apparatus, beginning from the point where mechanical energy is absorbed to generate current and ending with the completion of the working stroke of the engine. The ignition system includes the mechanical drive to the magneto or generator and the task imposed on the system is by no means completed when a spark has passed over the gap of the spark-plug. Ignition means the complete burning of the charge of gas in the cylinder at top dead-center, at the time the working stroke of the piston commences. The means employed to accomplish this result is the ignition system. In the present-day type of gasoline engine a spark produced by high-voltage electricity is almost universally used for ignition. This high-voltage electricity is produced by a transformer.