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Aerodynamic characteristics of horizontal tail surfaces

Description: From Summary: "Collected data are presented on the aerodynamic characteristics of 17 horizontal tail surfaces including several with balanced elevators and two with end plates. Curves are given for coefficients of normal force, drag, and elevator hinge moment. A limited analysis of the results has been made. The normal-force coefficients are in better agreement with the lifting-surface theory of Prandtl and Blenk for airfoils of low aspect ratio than with the usual lifting-line theory. Only partial agreement exists between the elevator hinge-moment coefficients and those predicted by Glauert's thin-airfoil theory."
Date: 1940
Creator: Silverstein, Abe & Katzoff, S

Boundary-Layer Transition on the N.A.C.A. 0012 and 23012 Airfoils in the 8-Foot High-Speed Wind Tunnel, Special Report

Description: Determinations of boundary-layer transition on the NACA 0012 and 2301 airfoils were made in the 8-foot high-speed wind tunnel over a range of Reynolds Numbers from 1,600,000 to 16,800,000. The results are of particular significance as compared with flight tests and tests in wind tunnels of appreciable turbulence because of the extremely low turbulence in the high-speed tunnel. A comparison of the results obtained on NACA 0012 airfoils of 2-foot and 5-foot chord at the same Reynolds Number permitted an evaluation of the effect of compressibility on transition. The local skin friction along the surface of the NACA 0012 airfoil was measured at a Reynolds Number of 10,000,000. For all the lift coefficient at which tests were made, transition occurred in the region of estimated laminar separation at the low Reynolds Numbers and approach the point of minimum static pressure as a forward limit at the high Reynolds Numbers. The effect of compressibility on transition was slight. None of the usual parameters describing the local conditions in the boundary layer near the transition point served as an index for locating the transition point. As a consequence of the lower turbulence in the 8-foot high-speed tunnel, the transition points occurred consistently farther back along the chord than those measured in the NACA full-scale tunnel. An empirical relation for estimating the location of the transition point for conventional airfoils on the basis of static-pressure distribution and Reynolds Number is presented.
Date: January 1940
Creator: Becker, John V.

Breaking and training colts.

Description: Describes methods training horses for farm use. Includes training or control methods for driving, riding, shoeing, and throwing.
Date: 1940
Creator: Stamburgh, V. G. (Vivian Guy), 1885-; Williams, J. O. (John Oscar), 1885- & Krantz, Earl B. (Earl Beach), 1893-

Business records for poultry keepers.

Description: Describes business methods to help poultry keepers with their production and marketing issues, discusses record-keeping methods, and includes suggestions to improve efficiency of a farmer's poultry business.
Date: 1940
Creator: Johnson, E. R. (Ernest Reuben), 1892- & Lee, Alfred R., b. 1887.

The calculated effect of various hydrodynamic and aerodynamic factors on the take-off of a large flying boat

Description: Report presents the results of an investigation made to determine the influence of various factors on the take-off performance of a hypothetical large flying boat by means of take-off calculations. The factors varied in the calculations were size of hull (load coefficient), wing setting, trim, deflection of flap, wing loading, aspect ratio, and parasite drag. The take-off times and distances were calculated to the stalling speeds and the performance above these speeds was separately studied to determine piloting technique for optimum take-off.
Date: January 1, 1940
Creator: Olson, R E & Allison, J M

Cattle-Fever Ticks and Methods of Eradication

Description: Revised edition. This bulletin discusses the cattle-fever tick and methods for controlling it. Possible methods include dipping, pasture rotation, and arsenical dips. The life history of the tick is also discussed and instructions for constructing a concrete vat are given.
Date: 1940
Creator: Ellenberger, W. P. & Chapin, Robert M.

Celery growing.

Description: A guide to commercial celery-growing, with brief instructions for growing celery in home gardens. Includes descriptions of celery diseases and insect pests.
Date: 1940
Creator: Beattie, W. R. (William Renwick), b. 1870

Coal-Mine Accidents in the United States, 1937

Description: Report compiled by the U.S. Bureau of Mines including statistics on fatal and non-fatal accidents in coal mines located in the United States as well as data regarding the various operations (e.g., number of miners employed and average production). The information is organized into tables for comparison and the text draws some overall conclusions in the summary.
Date: 1940
Creator: Adams, William W.; Geyer, L. E. & Parry, M. G.

Constant-pressure blowers

Description: The conventional axial blowers operate on the high-pressure principle. One drawback of this type of blower is the relatively low pressure head, which one attempts to overcome with axial blowers producing very high pressure at a given circumferential speed. The Schicht constant-pressure blower affords pressure ratios considerably higher than those of axial blowers of conventional design with approximately the same efficiency.
Date: January 1, 1940
Creator: Sorensen, E.

Corn culture.

Description: A general guide to growing corn crops in the United States, including selection, land preparation, planting, culture, and insect and disease control.
Date: 1940
Creator: Richey, Frederick D. (Frederick David), b. 1884

Correlation of cooling data from an air-cooled cylinder and several multicylinder engines

Description: The theory of engine-cylinder cooling developed in a previous report was further substantiated by data obtained on a cylinder from a Wright r-1820-g engine. Equations are presented for the average head and barrel temperatures of this cylinder as functions of the engine and the cooling conditions. These equations are utilized to calculate the variation in cylinder temperature with altitude for level flight and climb. A method is presented for correlating average head and barrel temperatures and temperatures at individual points on the head and the barrel obtained on the test stand and in flight. The method is applied to the correlation and the comparison of data obtained on a number of service engines. Data are presented showing the variation of cylinder temperature with time when the power and the cooling pressure drop are suddenly changed.
Date: January 1, 1940
Creator: Pinkel, Benjamin & Ellerbrock, Herman H., Jr.