last conference, which was held during February, 1929, the ArmyNavy Aircraft Standards Board adopted standards covering 31 materials, 16 parts, 11 types of instruments, and 17 engine accessories. These standards are adopted not only in terms of their utility to the Army and Navy, but with full consideration as to their probable value to civil aeronautics and the related industries. Accordingly, these standards are being used to an increasing extent by commercial aviation interests. Considerable effort is expended by the bureau in the development and use of new materials. Upon ascertaining their superiority over existing materials, standards are prepared for the guidance of the various units concerned. One example of note is the general substitution of chrome molybdenum steel for carbon steel. Chrome molybdenum steel has accordingly been accepted as a standard aircraft structural material and specifications have been prepared covering this material in all of its forms. Another important material recently developed and for which specifications have been prepared is domestic woven parachute silk. With the assistance of the Bureau of Standards, the Silk Association of America, and interested silk manufacturers, it has been possible to develop a highly satisfactory type of silk cloth for parachute purposes which is now being manufactured in this country. This is considered a decided advantage, as previously it was necessary to procure this material from foreign sources. BUREAU OF CONSTRUCTION AND REPAIR The Bureau of Construction and Repair represents the Navy Department on 33 committees of the Federal Specifications Board, 9 sectional committees of the American Standards Association, 5 committees of the American Marine Standards Committee, and 12 committees of the American Society for Testing Materials. In its work on standardization, the bureau has been cooperating closely with other Government departments and bureaus and with the following organizations: The bureau is actively collaborating with the above organizations in the national standardization movement, and wherever practicable in the work under its cognizance has put into practical effect those standards which have been approved for Government use or which have been adopted as national industrial standards. During the past year the bureau has continued its research and tests, both service and laboratory, looking toward the development of new materials or the improvement of existing materials. During the past year 21 Navy Department specifications have been prepared under the cognizance of this bureau and 70 Navy Depart 88079-306 ment specifications have been revised. Some of the materials in which noted improvements have been made are: Studies are being made on other materials. It is anticipated these studies will result in further improvements and standardization in materials, such as: Welding rods and machines. High elastic limit steel. Corrosion resisting steel gasoline tanks. Corrosion resisting steel valves. Chromized cast steel castings. Copper bearing steel. Corrosion of rivets. Corrosion of pipe. New paint formulæ. BUREAU OF ENGINEERING The bureau maintains its relations with other Federal departments, and with industry in general, as to standardization and specification formulation and revision through the medium of the following technical societies and committees: Federal Specifications Board: 16 committees. American Standards Association: Council, and 31 sectional committees. American Society of Mechanical Engineers: 7 sectional and 4 standard- American Marine Standards Committee: Executive board and 12 subcommittees. National Screw Thread Commission. American Gage Design Committee. American Institute of Electrical Engineers: 2 committees. American Institute of Radio Engineers: 1 committee. Commission. of the International National Electric Light Association: 2 committees. Electrotechnical Advisory committee on nonferrous metals of the Bureau of Standards. During the past year, the bureau has investigated in laboratories under its control a very considerable number of different types of apparatus, materials, and processes, with a view to selecting the best available in the commercial field for standardization, methods of employment, and for the preparation of adequate specifications. In some cases investigation has been continual from previous years, in others investigation has just been inaugurated. Typical examples are as follows: Portable lead acid batteries. Electric heaters, air, for shipboard use. Electric heaters, radiant. Hard fiber for instrument board use. Asbestos, linen, and silk insulating tapes. Portable electric drills. Motors and controllers (direct current). Portable electric ventilating sets. Motion picture projectors. Outboard gasoline engines. Fireroom draft gages. Water meters. Fuel oil meters. Pump governors. Temperature regulators. Vacuum traps. Propeller type forced draft blower. Hard rubber jars for submarine storage batteries. Electric telegraphs (alternating current) for shipboard use. Antinoise telephones for shipboard use. Storage battery testing outfits. Radio high frequency receivers and transmitters. Radio wave propagation. Materials having piezo-electric effects. Instruments for measuring high frequencies. Radio traps. Devices for measuring and recording the direction of static. Equipment for the transmission of photographs. Equipment for writing maps and sketches. Equipment for measuring airplane and submarine antenna constants. Apparatus for testing ball bearings. Bolts, nuts, and screws. Taps and dies. Miscellaneous valves for shipboard use. Heat insulating materials for use with temperatures about 1500° F. Antiseize compound for use in threaded aluminum and aluminum alloy parts. Copper-nickel alloy condenser tubes. Spring material for Diesel engine valves. Boiler feed water treatment. Chromium plating in naval use. Centrifugally cast iron liners for large air pumps. Corrosion fatigue of metals. The activities of this bureau contribute to formulation of standards through its representatives who serve as members of various technical committees of the Federal Specifications Board, and have continued to act in an advisory capacity to other committees charged with matters of interest to the medical department. Medical supplies and equipment purchased for the Navy, and for the Veterans' Bureau, also X-ray apparatus for the Bureau of Indian Affairs are inspected and tested for conformity to specifications at the United States Naval Medical Supply Depot, Brooklyn, N. Y. BUREAU OF NAVIGATION The standard of time in the United States is set by the earth's rotation, the determination of which is made by the Naval Observatory_maintained in Washington under the jurisdiction of the Bureau of Navigation of the Department of the Navy. The Naval Observatory has membership on the National Committee on Calendar Simplification and membership on seven international commissions of the International Astronomical Union. The observatory has investigated the following subjects with a view toward improving quality of material or character of design by means of new specifications, modified specifications, operating instructions, or detailed reports: In some instances investigation has been completed and information made available, while in others research is still under way. With reference to the work of the Hydrographic Office, Bureau of Navigation, the work of this office calls for standardization along special lines which is carried on between other executive departments under authority of Executive Order 30, September, 1919, creating the Board of Surveys and Maps, in which the office has membership for the purpose of coordination, and the standardization of its chart and map construction. The Hydrographic Office also maintains membership on the United States Geographic Board for the purpose of standardizing names entering into its charts and publications; also closely cooperates with the hydrographic services of all foreign nations and maintains complete exchange of all publications in accordance with general practice. In 1921 the International Hydrographic Bureau was established for the purpose of standardizing and making uniform the practices of the hydrographic offices maintained by the various nations. The United States is a member of the International Hydrographic Bureau and at present has a member on the governing board. Through the coordinating agencies mentioned above, effort is constantly directed toward standardization of forms, symbols, characters, and methods of surveying, chart construction for navigation and aviation charts, and the publication of nautical books. BUREAU OF ORDNANCE The Bureau of Ordnance is a member of the Navy Department Specifications Board, technical committees of the Federal Specifications Board, National Screw Thread Commission, and the American Standards Ássociation. Through its membership in these organizations the bureau takes an active part in specification-making and standardization. The Bureau of Ordnance, through its subsidiary plants, such as the Naval Gun Factory; naval powder factory, Indianhead; naval torpedo station, Newport, R. I.; and naval ordnance plants, Baldwin, L. I., and South Charleston, W. Va., maintains a large manufacturing organization. The details of ordnance material manufactured are designed by the bureau's engineering and designing department. Complete information required for manufacturing purposes, relative to material used, dimensions, fitting of parts, tolerances, etc., is shown on the drawings. Up to the present time specifications have been referred to on the drawings by the Navy Department numbers, and the tolerances, fits, and finishes desired by a special system which has been standardized and used by the bureau for a great many years. Design draftsmen in the bureau are required to be fully conversant with Navy Department specifications and the other manufacturing standards referred to. At the present time the bureau has on file 146,000 ordnance drawings and 75,000 ordnance sketches, on most of which reference is made to standard Navy Department specifications and Bureau of Ordnance manufacturing standards. As Federal specifications have been promulgated, it has been the practice to print them in leaflet form, each bearing the old Navy specification number to which it corresponds or from which it has been taken. This serves as a cross-reference between Federal specification numbers and Navy Department specification numbers and makes it |