Airplane Systems Research Articles

Feeder Impedance of Variable-Speed and Constant-Frequency Generating Systems for Airplanes

The impedance of feeders used with variable-speed and constant-frequency (VSCF) generating systems in airplanes is severely affected by the non-sinusoidal generator current and the airplane frame. The above effect was experimentally investigated for frequencies from 1500 to 3500 cps. Data obtained are necessary for the analysis of system transient and steady-state behavior. Impedance curves were constructed as an aid in the determination of the optimum configuration and location of feeder cables for VSCF systems.

Feeder-fault protection for D-C aircraft generators

THE electric system of the modern airplane must provide continuity of electric power to all load distribution circuits regardless of the occurrence of faults. The aircraft industry has widely accepted the necessity of generator feeder-fault protection to accomplish this objective. There is, however, no general agreement to be found when determining the means of obtaining this protection.

Porcelain Enamel as a Corrosion Resistant Coating for Metals

The use of porcelain enamel as a decorative finish is briefly discussed as contrasted to its more recent use as a corrosion resistant coating. The properties of different types of enamels are enumerated as regards methods of application and resistance to acid, weather, water, inorganic salts and other chemicals. Some specific applications for corrosion resistance are discussed which include hot water storage tanks, housings for airplane and tank engine exhaust systems, glass-lined pipe for natural gas containing hydrogen sulfide, chemical process equipment, and street or advertising signs. Resistance to impact damage is also discussed.