1、/ MIL-C-L47LA Lb 77777Ob OL7LO87 3 =- 6 =-cl 9 -ay M I L-C-I 8491 A( AS) 30 June 1969 SEI? ERSEDING MIL-C-18491 (Aer) 3 March 1955 / r. ., . i T. MILITARY SPECIFICATION e CURTAIN, FLAK PROTECTIVE This specification has been approved by the Naval Air Systems Command, Department of the Navy. 1. SCOPE
2、1.1 This specification covers the requirements for one type and size of flak protective curtain. 2. APPLICABLE DOCUMENTS 2.1 The following documents of the issue in effect on date of invitation for bids or request for proposal, form a part of this specification to the extent speci- fied herein: SPEC
3、 IF1 CATIONS Federal V-T-295 . Thread, Nylon I W -P-26 8 Paper, Kraft, Untreated, Wrapping DDD-L-2 O Label, for Clothing, Equipage, and Tentage, (General Use) PPP-B-636 Box, Fiberboard PPP-T-45 Tape, Gummed, Paper, Reinforced and Plain, for Sealing and Securing Military MIL-C -50 8 Cloth, Oxford, Ny
4、lon, 3 Ounce MIL-W-4088 Webbing, Textile, Woven Nylon A Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-C-18471A 16 7797706 0191070 T = MIL- C- 18491A(AS) SPECIFICATIONS Military (Continued) MIL- T- 5 03 8 MIL-C- 7812 MIL- C- 1236 9 MILE16491 ST
5、ANDARDS Federal FEBSTD-595 FED-STD-751 Military MIGSTD-105 Tape, Textile and Webbing, Textile, Reinforcing, Nylon Cloth, Nylon, Ballistic Cloth, Ballistic, Nylon Grommet, Metallic Colors Stitches, Seams, and Stitchings Sampling Procedures and Tables for Inspection by Attributes MIL-STD-129 Marking f
6、or Shipment and Storage (When requesting any of the applicable documents, refer to both title and num- ber. All requests should be made via the cognizant Government quality assurance representative. Copies of this specification and other unclassified specifications and standards required by contract
7、ors in connection with specific procurement functions should be obtained upon application to the Commanding Officer, Naval Publications and Forms Center (Code 1051), 5801 Tabor Avenue, Philadelphia, Pennsylvania 19120. All other documents should be obtained from the procuring activity or as directed
8、 by the contracting officer.) 3. REQUIREMENTS 3.1 Materials and components - The materials and components shall conform to applicable specifications and standards as listed or required herein. Cloth - - 3.1.1 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from
9、 IHS-,-,-. - MIL-C-L471A 16 7777706 027Z09L Z M IL-C- 18491A(AS) 3.1.1.1 Cover - The cover cloth shall be fabricated from the nylon oxford The dycd cloth shall cloth conforming to MIL-C-508, Type I, Class 1. imately match FED-STD-595 Olive Drab, Color Number 34087. have :it Icast good“ colorfastness
10、 to lighl and laundering. The color of the cloth shall approx- 3.1.1.2 Filler - The filler cloth shall be fabricated from the ballistic ny- lon cloth conforming to MIGC-7812, Type II, or MIGC-12369 (see 3.2 and Figure 2). The color of the cloth shall be natural. c 3.1.2 Frame - The frame shall be fa
11、bricated from the nylon webbing conforming to MIGW-4088, Type XV, 2 inches wide. match the color of the cover cloth, 3.1.1.1. The color shall approximately 3.1.3 - Ties - The ties shall be fabricated from the nylon tape conform- ing to MIL-15038, Type III, 3/4 inch wide. The color shall approximatel
12、y match the color of the cover cloth, 3.1.1.1. 3.1.4 Thread - The thread for all the sewing operations shall be nylon conforming to V-T-295, Type I or II, Class 1 or 2, Size E. The dyed thread shall have at least “good“ colorfastness to light and laundering and shall approximately match the color of
13、 the cover cloth, 3.1.1.1. 3.1.5 Grommets - The grommets shall be anodized aluminum conform- ing to MIL-G-16491, Type I, Class 5, Size Number 2. 3.2 Design - The flak protective curtain shall consist of two sets of 5 or 7 plies of the filler cloth (see Figure 2) covered on the visible sides with the
14、 cover cloth and attached to a webbing frame containing grommets and tie tapes. The flak protective curtain shall cor.iform in appearance to Figure 1. 3.3 Construction - The details of the construction shall conform to Figures 1 through 3. The cut edges of the nylon cloths, webbings, and tapes shall
15、 he senrcd or treated to prcvent fraying. No sharp edges sh:rll bc formcad. lhe scaring or thc nwthoti of tre:itnient shall not bc dcletcrious to the cloth, wcbthiiig, nr lape nor advcrscly cffwt :my proccss of the m:inu;ic!turing. Whcncvcr pr:wtic:il, lha sclvagc cdges of thc. wvcr and filler cloth
16、s shall bo utilized in thc f:thric:rtion of thc curt:kin. The length :iiid width of each cover and fillcr ply shall not hc ohtaincd hy joining to- gether two or more pieces of the clolh. continuous lcnglh and width without :my seiims. The frame sh;ill he f;thric:ited from one continuous length of th
17、e webbing. tinuous length of the tape. Thcl cover and each filler ply sh:iII he one Each tie tape shall bc fabricated from one con- -L 3.3.1 Seams and stitching - All the seams used in the fabrication of the curtain shall conform to Figures 1 through 3, as applicable. All the regular sewing and the
18、quilting stitching shall be accomplished with Stitch Type 301, conforming to 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL- C- 18491 A(AS) FED-STD-751 , with 10 lo 12 stitches per inch, except for thc quilling sfifcshing, which shd1 cotit:iin
19、 4 to 6 stitchcs pcr inch. If desired, tlic c?tigcs 01 v:cli stf of filler plios ni:iy ing lo FEI)-SID-751. The overedgo stitching shall contniii 4 io (i stitches pcr iicli and the bight shall be l/Z inch minimum. I ovr!rcitigcd stitchod together with Stitch Iypo 502, 503, 50.1, or 505 cwiiiorni- 3.
20、3.1.1 Sewing - Each row of stitching shall be straight and parallel to the seam edge or to the previous row of the quilting stitching, as applicable. The 8 straightness of the stitching, in any row, shall be maintained within a tolerance of plus or niiiius 1/32 inch, The ends of the stitching that a
21、re not caught in other seams or stitching shall be backstitchcd, by overlapping on themselves, a minimum of 1/2 inch. Thread breaks, skips, rind runoffs shall be overstitched not less than one inch. The thread tension shall be maintained so that there shall not be any loose or tight stitching Lind t
22、he lock shall be embedded in the materials sewn together. No seam shall be twisted, puckered, or pleated and no part of the curtain shall be caught in an unrelated operation or seam. All the thread ends shall be trimmed to a length of 1/4 to 3/8 inch und except for the frame webbing and tie tapes, n
23、o raw or cut edges shall be visible. All the seam edges shall be properly forced out and shall not contain any folds. 3.4 Dimensions - The dimensions of the assembled flak protective curtains, width of the seams and hems, size of the quilting pattern, and the dimen- sions and locations of the compon
24、ents and stitching shall conform to Figures 1 through 3, as applicable, when determined as specified in 4.3.2. 3.5 Weight - When weighed as Bpecified in 4.3.3, the weight of each curtain shall not exceed 10.5 pounds. 3.6 Label - The curtain shall contain an identification label, 1-5/16 by 3 inches,
25、conforming to DDD-G20, Type I, Class 1, Launderable Label. The label shall be securely sewn on all the four sides in the location specified in Figures 1 and 3. The label shall contain the following information: CURTAIN, FLAK PROTECTIVE MI L- C- 1 840 1 A (AS) CONTRACT OR ORDER NO. i1iAME OF MANUFACT
26、URER DATE OF MANUFACTURE (Month and Year) MAXIMUM WEIGHT 10.5 LBS. 3.7 Workmanship - After completion of the final assembly, the cur- tains shall be thoroughly cleaned and all loose thread, lint, and foreign matter shall be removed. tcnr, cut, mciid. burn, needle chew, spot, or stain. without distor
27、tion, damage, splitting, or cutting of the webbing and shall not contain The flak protective curtains slinll not contain any nonspccified hole, Each grommet shall be clinched 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-l8491A(AS) any crac
28、k, nick, burr, sliver, sharp edge, corrosion, scale, pit, or dent. Because of the emergency use of this item, the importance of providing a product of uniform excellent quality cannot be overemphasized. The flak protective curtains shall be uniform in quality and shall be free from irregularities or
29、 defects which could ad- versely affect performance, reliability, or durability. The flak protective curtains shall conform to the quality and grade of product established by this specification. The occurrence of defects shall not exceed the acceptance criteria established *herein. c 4. QUALITY ASSU
30、RANCE PROVISIONS 4.1 Responsibility for inspection - Unless otherwise specified in the contract or purchase order, the supplier is responsible for the performance of all inspection requirements as specified herein. Except as otherwise specified in the contract or order, the supplier may use his own
31、or any other facilities suitable for the performance of the inspection requirements specified herein, unless disapproved by the Government. tions set forth in the specification where such inspections are deemed necessary to assure supplies and services conform to prescribed requirements. The Governm
32、ent reserves the right to perform any of the inspec- 4.2 Quality conformance inspection - The sampling and inspection levels shall conform to MIL-STD-105. The quality conformance inspection shall consist of the following: Visual examination of the flak protective curtains Dimensional check of the fl
33、ak protective curtains Weight of the flak protective curtains Preparation for delivery 4.2.1 Sampling - 4.2.1.1 Inspection lot - 4.2.1.1.1 Curtain - An inspection lot size shall be cxpressed in units of one curtain made essentially under the same conditions and from the same materials and components
34、. The sample unit shall be one curtain. 4.2.1.1.2 Preparation for delivery - An inspection lot size shall be expressed in units of one fully prepared shipping container, containing curtains, fully prepared for delivery from essentially the same materials and components. The sample unit shall be one
35、shipping container, containing curtains, fully prepared for delivery with the exception thnt it need not be sealed. 4.2.1.2 Sampling for the examinations and tests of the curtains and prep- aration for delivery - The sample size, acceptance criteria, examinations, and tests required for the curtains
36、 or the preparation for delivery, as applicable, shall be as specified in Table I. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-L49LA 3b W 7797706 0373094 7 W M I G C- 1 8 4 9 1 A (AS) TABLE I SAMPLE SIZE, ACCEPTANCE CRITERIA, EXAMINATIONS
37、, AND TESTS OF THE CURTAINS AND PREPARATION FOR DELIVERY INSPECTION Visual examina- tion Dimensional check Weight Preparation for delivery PARAGRAPH 3.2 through 3.3.1.1, 3.6, 3.7, and Figures 1 through 3, as applicable 3.4 and Figures 1 through 3, as applicable 3.5 Section 5 METHOD 4.3.1.1 and Table
38、 II 4.3.1.1, Table III, and 4.3.2 - 4.3.3 4.3.1.2 and Table IV SAMPLE SIZE Inspection Level II Inspection Level S-3 Inspection Level S-1 Inspection Level S-2 ACCEPTANCE CRITERIAL/ - An acceptable quality level of 2.5 defects per 100 units for major defects and 4.0 defects per 100 units for minor de
39、fe c ts Aii acceptable quality level of 4. O defects per 100 units - An acceptable quality level of 1.5 defects per 100 units - An acceptable qualitj level of 2.5 defects per 100 units - i/ The sampling pian acceptance numbers shall apply collectively to all the charac- teristics within a stated acc
40、eptable quality level. 4.3 Inspection methods - 4.3.1 Visual examination - 4.3.1.1 Curtains - Each of the curtains, selected as a sample unit from the lot, shall be thoroughly checked dimensionally and examined visually to determine conformance to this specification. The classification and list of d
41、efects, Tables II and III, as applicable, shall be used to classify and enumerate the defects found. 4.3.1.2 Preparation for delivery - Each of the fully prepared shipping con- tainers, containing curtains, selected as a sample unit from the lot, shall be visually examined to determine that the pack
42、aging, packing, and marking conform to this speci- fication. The list of defects, Table IV, shall be used to enumerate the defects found. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-LLI71A Ib W 7777906 0373075 7 W MIL-C-l8491A(AS) TABLE I
43、I CLASSIFICATION OF DEFECTS FOR THE VISUAL EXAMINATION OF THE CURTAINS DEFECT GENERAL a. Any non-specified hole, scissors or knife cut, tear, mend, burn, or weakening defect such as smash, multiple float, loose slub, needle chew, or abraded area b. Color of any component not as specified, not unifor
44、m in shade, or contains one or more shade bars c. Any thread end not trimmed to a length of 1/4 to 3/8 inch or loose thread ends d. Any spot or stain e. Any cut edge not seared or treated; any sharp edge formed due to searing or method of treatment f. Any tie tape or frame webbing not one continuous
45、 length g. Number of the filler plies per curtain are less than 10 or 14, as applicable (see 3.2 and Figure 2) GROMMETS a. Any loose, misaligned, distorted, or contains any crack, sharp edgct, nick, burr, metal sliver, dont, corrosion, scale, or pit b. Any surface unclean, contains embedded foreign
46、matter, finish missing, or improperly finished c. Any grommet improperly clinched, resulting in cutting of the webbing COMPONENTS AND ASSEMBLY a. Any conipoiient not as specified or any defect of a compo- nent or defect of assembly not herein classified MAJOR X X X X X - i/ X X X X X 7 Provided by I
47、HSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-L47LA 16 U 7777706 OL7107b O MIL- C- 18491 A(AS) TABLE II (Cohtinucd) DEFECT COMPONENTS AND ASSEMBLY (Continued) b. Any component, component part, or required operation omitted, or any operation improperly per
48、formed not here- in classified SEAMS AND STITCHING a. Accuracy of Seaming: 1. Any seam, hem, or attachment of any component twisted,. puckered, pleated, or caught in an unre- lated operation or stitching 2. Any joining seam in any cover or filler ply 3. Any seam edge not properly forced out or conta
49、ins any fold 4. Ends of stitching that are not caught in other seams or stitching: (a) Not securely backstitched (b) Secure but backstitched for a distance less than 1/2 inch or the backstitching is not overlapped on itself 5. Thread breaks: (a) Not securely overstitched (b) Secure but overstitched for a distance less than one inch b. Gage of stitching - 2/: 1. Any stitching irregular, unevenly gaged, or various stitc
