A radar method of calibrating airspeed installations on airplanes in maneuvers at high altitudes and at transonic and supersonic speeds (open access)

A radar method of calibrating airspeed installations on airplanes in maneuvers at high altitudes and at transonic and supersonic speeds

A method of calibrating the static-pressure source of a pitot static airspeed installation on an airplane in level flight, dives, and other maneuvers at high altitude and at transonic and supersonic speeds is described. The method principally involves the use of radar-phototheodolite tracking equipment. The various sources of error in the method are discussed and sample calibrations are included.
Date: August 31, 1949
Creator: Zalovcik, John A.
System: The UNT Digital Library
A method of analysis of V-G records from transport operations (open access)

A method of analysis of V-G records from transport operations

A method has been developed for interpreting v-g records taken during the course of commercial transport operation. This method involves the utilization of fairly simple statistical procedures to obtain "flight envelopes," which predict that, on the average, in a stated number of flight hours, one value of airspeed will exceed the envelope, and one positive and one negative acceleration increment will exceed the envelope with equal probability of being experienced at any airspeed. Comparison with the actual data obtained from various airplanes and from various airlines indicates that these envelopes predict the occurrences of large values of acceleration and airspeed with a high degree of accuracy.
Date: August 31, 1945
Creator: Peiser, A. M. & Wilkerson, M.
System: The UNT Digital Library
Correlation of cylinder-head temperatures and coolant heat rejections of a multicylinder, liquid-cooled engine of 1710-cubic-inch displacement (open access)

Correlation of cylinder-head temperatures and coolant heat rejections of a multicylinder, liquid-cooled engine of 1710-cubic-inch displacement

"Data obtained from an extensive investigation of the cooling characteristics of four multicylinder, liquid-cooled engines have been analyzed and a correlation of both the cylinder-head temperatures and the coolant heat rejections with the primary engine and coolant variables was obtained. The method of correlation was previously developed by the NACA from an analysis of the cooling processes involved in a liquid-cooled-engine cylinder and is based on the theory of nonboiling, forced-convection heat transfer. The data correlated included engine power outputs from 275 to 1860 brake horsepower; coolant flows from 50 to 320 gallons per minute; coolants varying in composition from 100 percent water to 97 percent ethylene glycol and 3 percent water; and ranges of engine speed, manifold pressure, carburetor-air temperature, fuel-air ratio, exhaust-gas pressure, ignition timing, and coolant temperature" (p. 207).
Date: August 31, 1948
Creator: Lundin, Bruce T.; Povolny, John H. & Chelko, Louis J.
System: The UNT Digital Library
Analysis of Jet-Propulsion-Engine Combustion-Chamber Pressure Losses (open access)

Analysis of Jet-Propulsion-Engine Combustion-Chamber Pressure Losses

From Summary: "The development and the use of a chart for estimating the pressure losses in jet-engine combustion chambers are described. By means of the chart, the pressure losses due to fluid friction and to momentum changes in the air flow accompanying combustion can be separately evaluated. The over-all pressure losses computed from the pressure-loss chart are within 7 percent of the experimental values for the three types of combustion chambers considered herein."
Date: July 31, 1946
Creator: Pinkel, I. Irving & Shames, Harold
System: The UNT Digital Library
Investigation of Fretting by Microscopic Observation (open access)

Investigation of Fretting by Microscopic Observation

"An experimental investigation, using microscopic observation and color motion photomicrographs of the action, was conducted to determine the cause of fretting. Glass and other noncorrosive materials, as well as metals, were used as specimens. A very simple apparatus vibrated convex surfaces in contact with stationary flat surfaces at frequencies of 120 cycles or less than l cycle per second, an amplitude of 0.0001 inch, and load of 0.2 pound" (p. 135).
Date: August 31, 1949
Creator: Godfrey, Douglas
System: The UNT Digital Library
A Method of Analysis of V-G Records from Transport Operations (open access)

A Method of Analysis of V-G Records from Transport Operations

A method has been developed for interpreting V-G records taken during the course of commercial transport operation. This method involves the utilization of fairly simple statistical procedures to obtain "flight envelopes," which predict that, on the average, in a stated number of flight hours, one value of airspeed will exceed the envelope, and one positive and one negative acceleration increment will exceed the envelope with equal probability of being experienced at any airspeed. Comparison with the actual data obtained from various airplanes and from various airlines indicates that these envelopes predict the occurrences of large values of acceleration and airspeed with a high degree of accuracy.
Date: August 31, 1945
Creator: Peiser, A. M. & Wilkerson, M.
System: The UNT Digital Library
Experimental investigation of the effects of viscosity on the drag and base pressure of bodies of revolution at a Mach number 1.5 (open access)

Experimental investigation of the effects of viscosity on the drag and base pressure of bodies of revolution at a Mach number 1.5

Models were tested to evaluate effects of Reynolds number for both laminar and turbulent boundary layers. Principal geometric variables investigated were afterbody shape and length-diameter ratio. Force tests and base-pressure measurements were made. Schlieren photographs were used to analyze the effects of viscosity on flow separation and shock-wave configuration and to verify the condition of the boundary layer as deduced from the force tests. The results are discussed and compared with theoretical calculations.
Date: January 31, 1947
Creator: Chapman, Dean R. & Perkins, Edward W.
System: The UNT Digital Library