FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1917
1917 - 1224.PDF
NOVEMBER 22, 1917. INTERNATIONAL AIRCRAFT STANDARDS. IN aeronautical engineering circles it has been a matter of some speculation what, precisely, would be the effect of possible divergences in the aircraft standards to be decided upon by the U.S.A., and in how far any such differences would affect the co-operation of America with the Allies. The International Aircraft Standards Board, which has been holding meetings for the purpose of standardising air- craft material specification for purchases of the Allied Govern- ments in America, has decided on the " International Aircraft Standards " published below. The I. A. S. B. is composed of representatives of the Aircraft Departments of Great Britain (Canada), France, and Italy, and of the Signal Corps of the Army and the Bureau of Construction of the Navy of the United States. The Board has endea- voured to standardise the materials entering into aircraft construction in such a manner as to conform with American manufacturing practice and at the same time to be of the greatest service to Allies making purchases in the U.S.A. The specifications are as follows :— Classification of International Aircraft Standards—Serial Numbers oftT.A.S.B. Specifications. The specifications receive serial numbers according to the following classification :— Series 1.—Covers general inspection and testing instruc- tions. Series 2.—Covers raw materials. Wood, ingot metals, &c. Series 3.—Covers fabricated material, such as bars, castings, &c. Series 4.—Covers fabricated parts, such as turnbuckles, ferrules, fittings, &c. Series 2 and 3 will be further subdivided according to the type of material :— 2F.—Fabrics and dope. 2N.—Non-ferrous metals. 2O.—-Oil and gasoline. 2S.—Steel and iron. 2V.—Varnish and glue. 2W.—Wood. Series 4 is subdivided as follows :— • . 4A.—Accessories. . • • 4E.—Engine. " _ • 4I.—Instruments. 4P.—Plane, frame, &c. 1L1.—List of Specifications. 1 Li.—List of Specifications. 1G1.—General specifications for testing and inspection of metallic materials. 1A1.—Methods of chemical analysis. ~ 2^1.—Chemical compositions of steels. 2N1.—Ingot aluminium. 2N2.—Ingot copper. 2N3.—Spelter. 3S1.—Carbon steel for case-hardening. 3S2.—Medium carbon steel bars and billets. 3S3.—Alloy steel bars and billets, 100,000 lbs. per square inch tensile strength. 3S4.—Alloy steel bars and billets, 125,000 lbs. per square inch tensile strength. 3S5.—Alloy steel bars and billets, 150,000 lbs. per square inch tensile strength. 3S6.—Alloy steel bars and billets, 175,000 lbs. per square inch tensile strength. 3S7.—Alloy steel bars and billets, 200,000 lbs. per square inch tensile strength. 3S8.—Alloy steel bars and billets, 225,000 lbs. per square , inch tensile strength. 3^9-—Alloy steel bars and billets for case-hardening, •" 170,000 lbs. per square inch tensile strength. 3S10.—Alloy steel bars and billets for case-hardening, 190,000 lbs. per square inch tensile strength. 3S11.—Tolerance on steel bars. 3S12.—High-strength steel wire. 3813.-19 non-flexible steel-wire cable 3S14.—7 by 7 non-flexible steel-wire cable. 3S15.—7 by 19 extra flexible steel-wiie cable 3S16.—Wire for acetylene welding. 3S17.—Wire for electric Welding. 3N1.—Gunmetal castings. . 3N2.—Manganese bronze castings. ' ' 3N3.—Phosphor bronze castings. 3N4.—Naval brass or equivalent alloy bars. 3N5.—Naval brass or equivalent alloy sheet. 3N6.—Sheet brass. 3N7.—Brass tubes. 3N8.—Sheet copper. 3N9.—Phosphor bronze strip. 3N10.—Babbitt metal. 3N11.—Aluminium alloy castings. 3N12.—Sheet aluminium. 4P1.—Turnbuckles. 4P2.—Ferrules and thimbles. , 1G1—General Specifications for the Testing and Inspection of Metallic Materials. GENERAL—1. These specifications will form part of all individual specifications for metallic materials. MATERIAL—2. (a) An analysis of each lot of material and of each heat of steel furnished to this specification shall be made by the manufacturer. The chemical composition thus determined shall be reported to the purchaser and the Govern- ment inspector, and shall conform to the requirements of the specification. (b) In the case of submission of lots of material of which the heat or identification marks are lacking or doubtful the manufacturer will be required to furnish analyses of a sufficient number of the articles submitted to satisfy the inspector of the uniformity of the lot. (c) An analysis may be made by the purchaser or Govern- ment inspector from a tube, sheet, bar, or test bar or casting representing each lot of material submitted, and the chemical analysis thus determined shall conform to the requirements specified. If the analysis of any one article does not conform to the requirements specified, analyses of two additionar articles of the same lot shall be made, unless otherwise noted, each of which shall conform to the requirements specified. (d) The methods for chemical analysis shall be those of the I. A. S. B. (e) The weight of sample taken for analysis shall be not less than 120 g., and the sample shall be clean, free from rust, oxide, and extraneous matter, and is to be taken with a slow-speed tool. (/) Drillings for analysis of bars, billets, or other regular shapes shall be taken parallel to the axis at any point midway between the centre and surface. (g) Drillings for analysis may be taken from broken tension or bend test specimens when physical requirements are specified. (h) Wire, tubing, sheets, and rods less than ij in. (31.75 mm.) in thickness, shall be samples through or across the entire section. (i) In case of suspected segregation (steel), a sample may be taken from a point on the axis and analyzed ; the per- centage of no element may exceed at this point by more than 15 per cent, that specified. ) In order to obtain evidence of possible unsoundness and piping, sample bars of steel may be nicked and broken for examination of fracture, (k) Drillings or cuttings for the analysis of irregularly shaped pieces (steel), for which no physical requirements are specified, shall be taken from both the thickest and the thinnest sections. Surface drillings shall be discarded. MANUFACTURE—3. (a) The materials shall be manufactured according to the best current practice. (b) Steel shall be manufactured or at least finished by the open-hearth, electric-furnace, or crucible process unless otherwise noted. (c) Sufficient discard shall be made from each ingot to secure freedom from piping and undue segregation. (d) The billets from which bars or forgings are made are to be rough turned or chipped to remove all surface defects which might produce seams in the finished bar or forging. No undercutting in chipping will be allowed. Heat Treatment.—(e) The manufacturer shall state the heat treatment recommended to give the physical properties specified for all steels which are to be used in the heat- treated condition. WORKMANSHIP AND FINISH—4. (a) The articles must be finished in a workmanlike manner and must be free from flaws, surface and other defects to which they are subject. (b) Any article may be rejected because of injurious de- fects or faults in manufacture at any time, notwithstanding that it has previously passed the physical and chemical tests ; it shall bs returned to the manufacturer at the latter's expense. This clause shall not bs taken to apply to materials fabricated after export. PHYSICAL PROPERTIES AND TESTS.—(a) Physical tests shall be carried out on testing machines of standard make, which are to be kept in good working condition. The manufacturer must satisfy the inspector that the testing machines are at all times properly calibrated. 1224
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
