Civil Aeronautics Administration Research Articles

Resonant-Circuit Constant-Current Regulators

Airport-approach and runway-marker light circuits are quite similar to the usual street-lighting circuits, except that the important additional feature of brightness control is required. Standard moving-coil regulators were found to be unsatisfactory for this purpose, and so the development of resonant-circuit constant-current regulators with built-in brightness control was fostered by the Army Air Forces. Four years of service have proved regulators of this type to be entirely satisfactory, and they have been adopted as standard by the Army, Navy, and Civil Aeronautics Administration. Resonant-circuit regulators have no moving parts and operate at high efficiencies and power factors, even at light loads. Detailed performance data, together with a comparison of resonant-circuit and moving-coil regulators, are presented in this paper.

Transactions section: Preprint of corresponding pages from the current Annual AIEE transactions volume: Resonant-circuit constant-current regulators

Airport-approach and runway-marker light circuits are quite similar to the usual street-lighting circuits, except that the important additional feature of brightness control is required. Standard moving-coil regulators were found to be unsatisfactory for this purpose, and so the development of resonant-circuit constant-current regulators with built-in brightness control was fostered by the Army Air Forces. Four years of service have proved regulators of this type to be entirely satisfactory, and they have been adopted as standard by the Army, Navy, and Civil Aeronautics Administration.

BOOK REVIEWS

Book reviewed in this article:Principles of Radio, by Keith Kenney, Editor of Electronics, Fellow Institute of Radio Engineers.The Chemical Formulary, by Editor‐in‐Chief, H. Bennett.Dictionary of Engineering and Machine Shop Terms, by A, H. Sandy, Silver Medalist, City and Guilds of London; Instructor and Lecturer, Mechanical Engineering Department, Borough Polytechnic, London. Revised by I. E. Berck, Ph.D.Theory of Functions, by Dr. Konrad Knopp, Professor of Mathematics at the University of Tubingen; translated by Frederick Bagemihl, M. A.Fundamentals of Algebra, Second Book, by Joseph A. Nyberg, Instructor in Mathematics, Hyde Park High School, Chicago.Better Colleges—Better Teachers, by Russell M. Cooper and Collaborators of 28 Colleges.Demonstrations and Laboratory Experiences in the Science of Aeronautics, A Guide for Teachers and Students, Prepared with the Cooperation of The Civil Aeronautics Administration and the American Council on Education. Contributing Authors: H. C. Christofferson, Chairman of Committee, Professor of Mathematics and Director of Secondary Education, Miami University; Guybert P. Cahoon, Professor of Education, Ohio State University; J. S. Richardson, Associate Professor of Education and Principal of McGuffey Schools, Miami University; Frank M. Fairchild, Coordinator, Department of Vocational Education Trades and Industries, Cincinnati Public Schools; Merrill Hamburg, Director of Vocational Education, Detroit Public Schools.Glue impregnated paper gaskets are used today on all jeep, tank, and airplane motors. This flexible, easily processed material is said to offer a tight seal, is easily removed, does not flux to metal, and is more vibration proof than regular gasket materials.

TESTS FOR DETECTION AND ANALYSIS OF COLOR BLINDNESS

Because of their great convenience and apparent simplicity of administration, polychromatic charts for the detection of defective color vision have been widely used in military and industrial fields for many years. Much dissatisfaction has been reported, and both the statistics of the Civil Aeronautics Administration and the results obtained by the Color Blindness Committee (Army Air Forces, United States Navy, Civil Aeronautics Administration and Inter-Society Color Council) indicate that, as they are used at present, polychromatic test plates are only about 50 per cent effective in screening out persons with defective color vision by the criterion of the test itself. In an endeavor to discover the reason for this failure, extensive investigations have been undertaken at the Knapp Memorial Laboratories utilizing a large battery of tests on all types of subjects, ranging from persons with normal to those with extremely defective color vision. Our results indicate that while defects in

Budget and Fiscal Program of the Civil Aeronautics Administration

Budget and Fiscal Program of the Civil Aeronautics Administration

STANDARD ILLUMINANTS IN RELATION TO COLORTESTING PROCEDURES

<h3>THE PROBLEM</h3> What is wrong with the present color-testing procedures? Why do examiners often fail to expose persons with defective color vision? Does the fault lie in the tests, the methods of administering them or the conditions under which they are administered? <h3>IMPORTANCE OF THE PROBLEM</h3><h3>In the Army.</h3> —An officer is shot because a cadet pilot fails to recognize a colored signal and fires an extra round. A bomber is shot down because a returning pilot fails to respond to a prearranged color signal code. Data of the Civil Aeronautics Administration show that a pilot who failed to pass the Ishihara test on the first attempt has a 50 per cent chance of passing a retest. <h3>In the Navy.</h3> —Tests conducted by members of the Committee on Color Blindness of the Inter-Society Color Council show that all the commonly used tests for color blindness are unreliable and largely ineffective

The Effect of Freezing‐Thawing and Wetting‐Drying Cycles on the Density and Bearing Power of Five Soils

Soil Science Society of America JournalVolume 9, Issue C p. 248-252 Miscellaneous Paper The Effect of Freezing-Thawing and Wetting-Drying Cycles on the Density and Bearing Power of Five Soils† Hans F. Winterkorn, Hans F. WinterkornSearch for more papers by this authorRollie G. Fehrman, Rollie G. Fehrman Director and Research Associate of the Soil Science Laboratory, respectively. The data presented were collected in the course of a rather extensive investigation on soil stabilization undertaken for the Airport Development Section of the Technical Development Division, Civil Aeronautics Administration. Grateful acknowledgment is made to Fred H. Grieme, Chief of the Section, for his kind and helpful interest, and for permission to use these data.Search for more papers by this author Hans F. Winterkorn, Hans F. WinterkornSearch for more papers by this authorRollie G. Fehrman, Rollie G. Fehrman Director and Research Associate of the Soil Science Laboratory, respectively. The data presented were collected in the course of a rather extensive investigation on soil stabilization undertaken for the Airport Development Section of the Technical Development Division, Civil Aeronautics Administration. Grateful acknowledgment is made to Fred H. Grieme, Chief of the Section, for his kind and helpful interest, and for permission to use these data.Search for more papers by this author First published: 01 January 1945 https://doi.org/10.2136/sssaj1945.036159950009000C0040x ‡ Contribution from the Soil Science Laboratory, School of Engineering, Princeton University, Princeton, N. J. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume9, IssueC1945Pages 248-252 RelatedInformation

The CAA-NYC Aviation Operations Institute

The Civil Aeronautics Administration —New York City Aviation Operations Institute was held on April 6th at La Guardia Field, New York City. It was arranged by Mr. O. P. Harwood, Regional Manager of the First Region of the Civil Aeronautics Administration for ninety-eight selected New York City teachers of aeronautics and school administrators, in conjunction with Dr. Frederic Ernst, Associate Superintendent in Charge of High Schools. The Institute program proved to be valuable to the highest possible degree. Teachers who were unable to take advantage of the opportunity offered to gain increased knowledge of aviation operations will undoubtedly be interested in a report of the activities covered during the course of a busy day.

The I.Ae.S. Annual Meeting

A paper by James George of the Civil Aeronautics Administration entitled “Development of Stall Warning Indicators”, covered three distinct types of stall warning devices. Two of these instruments will be commercially available in the near future. These will function successfully under all flight conditions except when ice has accumulated on the wings, and are considered suitable for use on private‐owner type aircraft since such aircraft are seldom involved in stall accidents where ice is a factor. The continuing programme involves the development of the third device suitable for use on existing air‐carrier type aircraft which will obtain an adequate Warning margin even when the wings are “iced up”. The results of wind tunnel and flight tests involving all three devices are presented and the entire problem is discussed in detail.

American Education and the War

IT is significant that the American magazine School Life has, for the duration of the War, been replaced by Education for Victory, “the official biweekly of the United States Office of Education Federal Security Agency”. The aim of this interesting periodical is to spread information throughout the forty-eight States about war effort in the schools and colleges of each State. Prominence is given to a declaration of the National Education Association as to the spirit of school teaching in war-time. However it may be for the fighting forces, the emotions of hatred and revenge have no place in the schools, especially among the younger children. “The spiritual casualties of war will be great enough and lasting enough without any help from the teaching profession”. Rather let the young people be taught a strong and positive love of freedom and fair play, and the strength of their opposition to slavery and injustice is assured. So Education for Victory tells of all that American schools and colleges are doing to help the war effort. Such activities as school gardening, and the securing of food for school lunches, appear to be carried out on an immense scale. The ever-pressing necessities of the war situation have directed closer attention than ever before to the problem of adequate nutrition. In still more direct ways than these, the schools are doing their share of effort. High-school students may now take the ground-school test of the Civil Aeronautics Administration. A few months ago, we are told, high-school students could only dream about aviation. Now tens of thousands of boys are studying pre-flight aeronautics, and 200 boys are actually learning to fly. Wings for Victory publishes also detailed information about what the higher educational institutions are doing for the War. Nearly five hundred of them have been approved tentatively, and subject to inspection will take allotted parts in war-training programmes. Obviously the normal course of scientific and technical education is being suspended, but on the other hand an immense stimulus is being given to forms of training that are destined to remain after hostilities have ceased.

Electrification of the Chicago airport

The electric system governing lights, signals, and controls for an airport with the area and traffic volume of the Municipal Airport at Chicago, Ill., presents problems not only in design, but in adapting to special conditions the standards specified by the Civil Aeronautics Administration for all United States airports. The results represent the latest practice, and include a number of unusual developments.

The Effectiveness of Aptitude Testing in the Civilian Pilot Training Program

The Civil Aeronautics Administration is attempting to supervise the primary training of approximately 36,000 pilots each year. In order to qualify for participation the applicant must be of at least sophomore standing in college-except in certain non-college programs-between the ages of 19 and 25, inclusive, and must pass a medical examination-which has recently been revised to approximate military standards. There are no aptitude tests required or recommended. The United States Army uses psychological tests for determining the aptitudes of men who enlist as privates in the infantry, etc., but in its Air Corps, where the problems of skill, intelligence, and ability to learn certain things are particularly important, it has no psychological testing program whatsoever. The nearest thing to psychological testing is a so-called neurological examination which consists in looking at scars on the tongue as evidence of epilepsy, etc. According to a recent letter from the Adjutant General about forty-five per cent of the applicants who are admitted to flight training are later washed-out. At the present time the military services are attempting to train about 10,000 pilots a year. At this rate of failure the Army must start with a group of 18,181 flight cadets in order to procure 10,000 trained pilots. At $3,800 each, the washed-out cadets must cost the government $31,084,000 a year. Surley there is some way for psychology to be used in reducing this figure.

Aircraft lighting

Aircraft lighting consists of: landing lights, position lights (wing and tail), formation lights, cabin lights (dome and worktable), indicator lamps, bomb-release signal light, interaircraft control-lamp assemblies, and instrument light. Landing Lights. The first landing lights on aircraft were attached to the lower surface of the airfoil or to the fuselage. These lamp assemblies used 240- or 420-watt 12-volt lamps, depending on the size and type of airplane. Later, to reduce the aerodynamic drag, the lamp assemblies were built into a mount, which was fastened to the leading edge of the wing. The next improvement was the insertion of the lamp assembly in the wings and the use of a curved cover glass to conform to the contour of the airfoil. Because of the increasing use of deicers and the use of the front surface of the wing to carry load, the leading-edge lamp assembly has been superseded by the present standard electric retractable-type landing-lamp assembly, which is mounted in the lower surface of the airfoil. Experimental tests are being conducted on sealed-beam lamps for aircraft landing lamps. The use of these lamps would permit increased wattage and light output and eliminate reflector maintenance. Position Lights (Wing and Tail). The Air Corps recently has standardized on the single-unit-type position light which will meet the requirements of the Civil Aeronautics Administration airline forward position lights and which will also meet the Air Corps formation flying requirements when used with a dimming resistor. The Civil Aeronautics Administration requirements for tail light is not met by the Air Corps because increased airplane performance can be accomplished by the use of a lamp assembly using a three-candlepower, T-3 1/4 miniature bayonet-base lamp.