1、MIL-B-32655A 66 3797706 0328407 b m - Ma-B- 12655A(SigC) 27 October 1958 Superseding Specification NO. MIL- B- 2655(SigC) 23 April 1953 MILITARY SPECIFICATION BALLOON, METEOROLOGICAL (BALLOON ML-39 i( )/AM) 1. SCOPE 1.1 This specification covers one type of sounding balloon designated as Balloon ML-
2、391( )/AM used with meteorological equipment. (See 6.3). 2. APPLICABLE DOCLJMENTS 2.1 The following specifications and standards, of the issue ineffect on date of invitation for bids, form a part of this specification: . SPECIFICATIONS MILITARY MIL-B-l4417(SigC) Balloons, Meteorological Pilot, Ceili
3、ng and Sound; Packaging of STANDARDS . MIL JTA RY MIL-STD- 105 Sampling Procedures and Tables for In- spection by.Apributes. . (Copies of specifications and standards, required by contractors in connection with specific procurement functions should be obtained from or as directed by the contracting
4、officer. Both the title and the identifying number or symbol should be stipulated when requesting copies. ) 3. REQUIREMENTS 1 3.1 Description. -The balloon covered by this specification is a sounding balloon which ascends rapidly to high altitudes carrying meteorological equipment for the purpose of
5、 obtaining upper air measurements. approval, as required by the invitation for bids and contract. (See 6.2(c)(l). ) 3.2 Preproduction simples. - The contractor shall furnish preproduction samples for I. . . . - . . . t . . . . . . . . . . ,. p:.7:.: t:;:;: l: ). .-.-_.- .-.- . ._. t:;:;:.:. l. -. .
6、. . I :I:1:r;:;:; ,. I. . I . t:. . . _- .-._ L ._- . . .- . . .“ ,. . -. . . . :.:=:;:r;.:.: . . , . 3.3 Service conditions. - Balloons supplied under this specification shall be capable * of meeting the requirement of 3.6 when inplated with hydrogen from a cylinder or hydrogen generator. . . herei
7、n, and shall be capable of meeting the tests specified in Section 4. *. . - 3.4 Construction. -. Balloons shall be manufactured in accordance with the requirements :- I . FSC 6660 .:- F -. -I-_- -I_ -_ . I-/ P . .- -_ -. . Copyright Communications - Electronics Command Provided by IHS under license
8、with CRAINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I MIL7B-12655(SigC) 3.4.1 Material. - Balloons shall be made.of the best quxiity neoprens The material shall be uniform texture, and shall be free of impurities. 3.4.2 Neck. - The balloon shall have a tubular
9、 neck of approximately uniform cross- sectional area. securely attached thereto. The neck shall be molded integrally with the body of the balloon or 3.4.2.1 Length. - The tubular portion of the neck shall have a minimim length of 4.5 inches. 3.4.2.2 Thickness. -The neck shall have a.minimum wall thi
10、ckness of O. 025 inch, and a maximum of O. 075 inch. . 3.4.2.3 Diameter. - The inside diameter of the neck shall be 12 1/8 inches. 3.5 Elongation. - The physical property used to measure the deterioration of neoprene balloons is the ultimate elongation since this is the primary property affecting th
11、e flight of the balloon. The ultimate elonpation before and after the accelerated aping test I (see 4.6) shall be: I a. Prior to aguig - 700% mi.nimum b. After aging - 600% minhum I- 3.6 Flipht requirements. - Balloons when inflated for flight shall each have a total lift of 3600 2 10 grams and when
12、 released shall carry a load weighing 1250 f. 35 grams ex - , 3 . ,. .:.:r I I . I . , . , . , . I . . r . ,- i . , . 1 . , . . . 1:.:-: r.: . fi:l: . t . . . . .- . . L ., . ,_ i * . i t- . . , . , . . .- . _ _ . _ ._.- - )_ . _ _. , . . . . . i Copyright Communications - Electronics Command Provid
13、ed by IHS under license with CRAINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-B- 12655 (SigC) . . . . . . 4.1.5.5 Acceptance or rejection of lot. - Acceptance or rejection of the lot represented bv the samDles submitted to the Government for performance of t
14、he flight test will be dlependent ;pon results of the test as reported tothe contractr and to the Covernrwnt in- spector by the Government testing agency. 4.1.6 Disposition of nonccnforming product. - When defective sample units or rejected lots are resubmitted for acceptance, such items shall be su
15、itably tagged or identified by equivalent means to indicate the cause of failure and means employed to-correct the fault. The record shall be presented to the Government when the items are resubmitted and shall become the property of the Government. This paragraph is not applicable to Government pro
16、- duction inspection for Flight Test. 4.2 Visual and mechanical inspection. - Balloons and containers shall be -inspected for defects in Table IV. approved marking and numbering in compliance with the requirements of 3.8 and 3.11 of the specification. specification requirements. Labels and markings
17、shall be inspected for conformance with inspection shall be made for other mechanical defects which are contrary to Classification of defects is as shown in Table IV. Table N - Classification of visual and mechanical defects Classification Defect Major Balloon contains foreign matter. Evidence of pa
18、tches. Date indicates balloon is more than 120 days old. Balloons improperly powdered or not powdered. Balloon container too small. Balloon contains holes or cracks. Balloon contains non-removable pinches Neck not securely attached to balloon. Wrong color. Minor Balloon contains marked or rubbed are
19、Es. Uneven coloring. Identification number incomplete, illegible or Container seams not completely sealed. Containers too large. Container markings incomplete, illegible or missing. . incorrect. 4.3 Procurement inspection of preparation for delivery. - This inspection shall con- form to Specificatio
20、n MIL-B- 14417 (SigC). 4.4 Neck dimensions test. - The following dimensions of the balloon neck shall be checked as described in the succeeding subparagraphs. portion of the neck shall be .measured with a suitable scale. The length shall conform to the requirements of 3.4.2.1 or the balloon shall be
21、 considered as having failed. 4.4.1 Length. - The length of the tuhular (approximately uniform cross-section area) 6. I r . . . ,. . . , . . . - . Copyright Communications - Electronics Command Provided by IHS under license with CRAINot for ResaleNo reproduction or networking permitted without licen
22、se from IHS-,-,-t MIL-B-12655A 66 W 9997706 OI2qI3 I I! , MIL-B- 12655(SigC) 4.4.2 Thickness. - The thickness of the neck shall be measured at ten different points. These measurements shall be within the limits specified in 3.4.2.2. or the balloon shall be considered as having failed. The measuremen
23、ts may be made of a double thickness of the neck provided the neck is flattened so that a true measurement is obtained of only the two neck thicknesses. over rigid tubes or cylinders of circular cross-section whose outside diameter shall be 7/8 and i-1/8 inches. require stretching to fit the 1-1/8 i
24、nch tube, or the balloon shall be considered as having failed. determine compliance with the rate of rise and bursting altitude requirements of 3.6. . . 4.4.3 Diameter. - The inside diameter of the neck shall be measured by fitting it . The neck shall fit the 7/8 inch tube without stretching, but sh
25、all 4.5 Flight test, - The balloon shall be subjected to the following flight test to . 4.5. 1 Conditioning for test, - Balloons shall be conditioned immediately before the . flight test by completely unfolding and immersing it in boiling water for five minutes. 4.5.2 Inflating. - Balloons shall be
26、given a surface inflation with helium which is 4.5.3 Loading. - The balloon shall be loaded with 1250 2 35 grams exclusive of the equivalent to a total lift of 3600 2 100 grams. weight of the balloon. The parachute shall be attached to the neck of the balloon by means of a nylon line (100 lb test) a
27、pproximately 50 feet long, and the radiosonde shall be suspended directly below the parachute. The Government will furnish the necessary radiosonde, parachute, and receiving equipment. have been carefully calibrated within one week prior to the time of flight. This load shall include a radiosonde wi
28、th a parachute attached. 4.5.4 Calibrating pressure element. - The pressure element of the radiosonde shall 4.5.5 Launching. - The balloon shall be released in free flight at any time between sunrise and two hours before sunset. 4.5.6 Record data. - The bursting altitude and the rate of rise of the
29、balloon aa defined in 3.6 shall be computed from.the radiosonde record. 4.5.6.1 Radiosonde failure. - If for any reason not the fault of the balloon, a radiosonde record for determining bursting height or rate of rise is not obtained, then a new sample shall be selected and the flight test shall be
30、repeated on-this substitute sample. 4.5.7 Balloon failures. - a. if failure of the balloon on the ground prohibits i release, it shall be interpreted as a flight that failed the bursting altitude requirement. A substitute sample balloon shall then be released to determine the rate of rise. i b. The
31、balloon shall be considered to have failed the rate of rise or bursting altitude tests if, during the flight test, it does not meet the requirements of paragraph 3.6 in these respects. 7 - I *r- . . .7 . . . . . -.e I I_ . c -_._ _.- 1 I- _._- -. p . ). . L . ,. i . c . . , . . L_I_ t; “ 1 . . I. .
32、I . ,. . _.-.-. I. . . - .-._-_ _-. . . - . .* . -. - . . ) . i. . i . I- .- . I . 1: . . . . . . . . . * . . l. . . . _ 8 . ._ -.- - . - . , . I . “ . . . , “ t , ,. . Copyright Communications - Electronics Command Provided by IHS under license with CRAINot for ResaleNo reproduction or networking p
33、ermitted without license from IHS-,-,- - _ MIL-B- 12655(SigC) 4.6 Accelerated aging test. - This test is intended to estimate the relative re- sistance of cured neoprene balloons to aging. No direct correlation between this accelerated test and the natural.life of neoprene balloons is given or impli
34、ed. 4.6.1 Nature of test. -This aging test of neoprene balloons consists of subjecting test specimens and/or samples having previously determined physical properties-to con- trolled elevated temperature in air at atmospheric pressure. posure to light. It does not include ex- 4.6.2 Apparatus for test
35、ing, - An air oven shall be used and shall meet the follow ing requirements : a. Provision shall be made to lay specimens or samples between two layers of cheese cloth on a perforated platform. b. The heating medium for the aging chamber shall be air circulated within the chamber at atmospheric pres
36、sure. c. of mechanical agitation. discharge because of the danger of ozone formation. The heated air shall be thoroughly circulated within the oven by means The air must not come in coritact with any electric motor brush d. e. The source of heat shall be located outside of the aging chamber proper.
37、The aging chamber temperature shall be controlled automatically at 100“ 1OC. f. chamber temperature. A recording thermometer shall be used to record and maintain the aging - g, Actual checks of the oven temperature shall be made by means of a maximum reading thermometer. 4.6.3 Procedure for accelera
38、ted aging. - The specimens for aging shall be placed in the aging chamber after the oven has been preheated to the operating temperature. Aging shall be for eight hours at the specified temperature. Simultaneous aging of a mixed group, of different compounds shall be avoided. 4.6.4 Number of test sa
39、mples. - a. b. Three balloons shall be selected for aging testa from each production lot. Three specimens from each balloon shail be used for testing the ultimate elongation of the unaged balloon film. elongation of the balloon film after aging. 4.6.5 Test samples. - Test material samples shall be 2
40、0 inch by 20 inch sections taken from preproduction and production balloons having the thickness of the production balloons. c. Three specimens from each balloon shall be used for testing the ultimate 8 . _. *. .,- :.f . . . * . . * , . . . -. -_*. - .- . . . . -.- -. . . . . . _._-. ._ i . . . - .
41、. * c . . . . Copyright Communications - Electronics Command Provided by IHS under license with CRAINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-B-LZb55A 66 = 7777906 0128415 5 mi . I d 7 MIL-B- 12 655 (SigC) 4.6.6 Test specimens. - a. Dumbbell-Shaped specim
42、ens shall be cut by using a standard die having a waist of O. 25 inches. The test specimens shall be free of wrinkles, creases, lumps and blisters. b. in the aging chamber. Gage lines used for measuring the elongation shall be applied after the specimens have been aged and just prior to the elongati
43、on test. Identically spaced gage lines shall be used on the unaged samples. The thickness of the test specimens shall be measured prior to exposure .*- - 4.6.7 Testing of specimens. - a. All specimens shall be tested on the Scott Tester as per A. S. T. M. , D412-51T, paragraph 5B. Except where the s
44、amples (specimens) are between 2 and 5 mils, a 2.5 lb weight shall be used on the Scott Tester. Elongation shall be as specified in 3.5. I b. All samples will be kept in a dessicator for a minimum of25 hours immediately prior to testing. c. All samples will be tested within 96 hours after removal fr
45、om. the aging chamber. 4.6.8 Test results. - The final value of ultimate elongation for the unaged balloon film shall be the median of results from the nine specimens tested. The median value is applicable to the aged specimens also. . 5. PREPARATION FOR DELIVERY 5.1 Preservation, packaging, packing
46、 and marking shall be in accordance with I Specification MIL-B- 14417(SigC). I 6. NOTES 6.1 Intended use- Balloon ML-39( )/AM is a sounding balloon with extremely high altitude bursting characteristics, used for day-time radiosonde ascents only. 6.2 Ordering data. - Procurement documents should spec
47、ify the following (a) Title, number, and date of this specification and any amendment thereto. (b) Typerequired. (c) Preproduction samples required: (1) Twenty of each item cited in section 1 are generally required so that lengthy environmental tests can be completed ori selected samples while compl
48、ete performance measurements can be made on the other samples. (See 3.2) (2) Preproduction pack(s) as follows: I a. Preproduction pack) shall be provided in accordance with Speci- b. Marking and sliipping of samples; c. Place of final inspection. fication MIL-B- 14417(SigC) 9 c c- I 1. -_ * -. . .- I F , “ . i . . . . i * . . . . I . . ,. .-.-. - -. , -* . . . . . . . ,. . _.- . . . i . . I. -. . :.:.:.: . Copyright Communications - Electronics Command Provided
