1、 MIL-DTL-48558C 14 September 2012 SUPERSEDING MIL-T-48558B(AR) 29 May 1990 DETAIL SPECIFICATION TELESCOPE, ELBOW - M138A1 This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers Telescope, Elbow: M138A1, which
2、 is one type of elbow telescope that provides an eight power magnification and an eight degree field of view. The telescope has a mil scale reticle for setting elevation. The reticle pattern is illuminated with a battery powered system. 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in th
3、is section are specified in sections 3 and 4 of this specification. This section does not include documents in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are c
4、autioned that they must meet all requirements of documents cited in sections 3 and 4 of this specification, whether or not documents are listed in this section. Comments, suggestions, or questions on this document should be addressed to: Commander, US Army ARDEC, ATTN: RDAR-QES-E, Picatinny Arsenal,
5、 New Jersey 07806-5000 or emailed to picaardecstdznbranchconus.army.mil. Since contact information can change, you may want to verify the currency of this address information using the ASSIST online database at https:/assist.dla.mil. AMSC N/A FSC 1240 DISTRIBUTION STATEMENT A. Approved for public re
6、lease; distribution is unlimited. INCH-POUND Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-48558C 2 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part
7、 of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-PRF-13830 - Optical Components for Fire Control Instruments; General Specification Governing the Manuf
8、acture, Assembly and Inspection of MIL-F-13926 - Fire Control Materiel, Manufacture, and Inspection, General Specification for DEPARTMENT OF DEFENSE STANDARDS MIL-STD-1916 - DOD Preferred Methods for Acceptance of Product (Copies of federal and military specifications, standards, and handbooks are a
9、vailable online at https:/assist.dla.mil/quicksearch/ or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094.) 2.2.2 Other Government documents, drawings, and publications. The following other Government documents, drawings, and publications for
10、m a part of this specification to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. U.S. ARMY ARMAMENT RESEARCH, DEVELOPMENT AND ENGINEERING CENTER (ARDEC) DRAWINGS 5549108 - Telescope, Collimating 7680631 - Diopto
11、meter 8565556 - Pressure Tester Two Station 10549199 - Adapter, Vibration and/or Shock 10558254 - Test Fixture 11747956 - Gage, Interchangeability, Maximum 13005104 - Telescope, Elbow: M138A1 (Copies of these drawings may be requested online at pica.drawing.requestconus.army.mil or from U.S. Army AR
12、DEC, ATTN: RDAR-EIS-PE, Picatinny Arsenal, NJ 07806-5000) Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-48558C 3 2.3 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of this
13、document and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 First article. When specified (see 6.2), a sample shall be subjected
14、to first article inspection in accordance with 4.2. 3.2 Conformance. A sample shall be subject to conformance inspection in accordance with 4.3. 3.3 Elbow telescope. The telescope shall conform to drawing 13005104. 3.4 Orientation. The telescope shall be able to be mounted in the orientation as stat
15、ed below: a. The telescope shall be able to be mounted on an appropriate fixture, which locates and holds in place the locating pin in a horizontal plane and positions the “V” Holder Assembly, drawing 10549272, 0.750 .002” above the pin and to the rear. b. The “V” located on holder assembly, drawing
16、 10549272, shall be seated over a 0.812” - 0.0005” diameter. The latch on the holder assembly shall be locked to a 0.500 0.001” diameter. c. A horizontal line of sight shall be provided which is parallel in azimuth to the plane defined by surfaces “X” and “Y” on drawing 13005104. 3.4.1 Collimation o
17、f reticle. With the telescope oriented as stated in 3.4, the boresight graduation cross shall coincide with a target 20 mils above the horizontal within 1.0 mil. The azimuth of the boresight cross shall coincide with a plane parallel to, but offset from, the plane defined by the surfaces “X” and “Y”
18、 on drawing 13005104 within 1.0 mil. 3.5 Environmental. 3.5.1 Storage temperature. The telescope shall be thermally stabilized at temperatures of +160 5F and -60 5F for a period of not less than 4 hours at each temperature. Upon return to and stabilization at standard ambient temperature, +60F to +9
19、0F, the elbow telescope shall meet the requirements of 3.7 through 3.13 inclusive. (See 6.6) 3.5.2 Operating temperature. The telescope shall meet the requirements of 3.10 inclusive while exposed to and thermally stabilized at temperatures of +145 5F and -50 Provided by IHSNot for ResaleNo reproduct
20、ion or networking permitted without license from IHS-,-,-MIL-DTL-48558C 4 5F for a period of not less than 4 hours at each temperature. Upon return to and stabilization at standard ambient temperature, +60F to +90F, the telescope shall meet the requirements of 3.7 through 3.13 inclusive. (See 6.6) 3
21、.5.3 Shock. The telescope, mounted to the test equipment using its standard attachment mechanism, shall withstand a total of 75 shock impulses along 3 mutually perpendicular axes as defined in Figure 1. Each shock impulse shall be a half sine wave with a time duration of .010 .001 seconds and peak a
22、mplitude for each shock impulse as shown in Table I. Subsequent to shock, the latch and cam lock used for attachment shall not have loosened, the telescope shall show no evidence of damage or physical failure, and it shall meet the requirements of 3.6 through 3.13 inclusive. (See 6.6) TABLE I. Shock
23、 orientation and impulse. Orientation Shock impulse and direction Number of impulses Longitudinal -130 gs, +130 gs 15 each direction Vertical -50 gs, +50 gs 15 each direction Transverse -50 gs 15 total FIGURE 1. Orientation of shock loads. 3.5.4 Vibration “A”. The telescope, mounted to the test equi
24、pment using its standard attachment mechanism, shall withstand a total of 270 minutes of sweep-cycle vibration. The vibration shall be applied for 90 minutes along each of the three mutually perpendicular major axes shown in Figure 1. A complete sweep-cycle shall consist of vibration from origin (5
25、Hz at 1 inch double amplitude) to mid-point (5 0.5 gs at 500 Hz) to origin, and shall have a duration of 15 1 minutes. Double amplitude shall be constant at 1 inch between 5 Hz and 10 Hz, and varied with frequency to maintain a constant 5 0.5 gs acceleration between 10 Hz and 500 Hz. Upon completion
26、 of vibration, the latch and cam lock used for attachment shall not have loosened, the telescope shall exhibit no evidence of damage or physical failure, and it shall meet the requirements of 3.6 through 3.13 inclusive. (See 6.6) Provided by IHSNot for ResaleNo reproduction or networking permitted w
27、ithout license from IHS-,-,-MIL-DTL-48558C 5 3.5.5 Vibration “B”. The telescope, mounted to the test equipment using its standard attachment mechanism, shall be vibrated in the vertical plane shown in Figure 1 for a total of 15 1 minutes of sweep cycle vibration. A complete sweep-cycle shall consist
28、 of vibration from origin (5 Hz at 1 inch double amplitude) to mid-point (5 0.5 gs at 500 Hz) to origin, and shall have a duration of 15 1 minutes. Double amplitude shall be constant at 1 inch between 5 Hz and 10 Hz and varied with frequency to maintain a constant 5 0.5 gs acceleration between 10 Hz
29、 and 500 Hz. Upon completion of vibration, the latch and cam lock used for attachment shall not have loosened, the telescope shall exhibit no evidence of damage or physical failure, and it shall meet the requirements of 3.6 through 3.13 inclusive. (See 6.6) 3.6 Collimation change, post shock and vib
30、ration. The line of sight established in 3.4.1 prior to the shock or vibration test shall not deviate more than .25 mil in azimuth or .25 mil in elevation due to subjecting the telescope to Vibration “A”, Vibration “B”, or Shock. 3.7 Sealing. The elbow telescope unit shall be capable of holding dry
31、nitrogen at a minimum internal pressure of 5 psig for a period of 1 hour 5 minutes without the loss of pressure in excess of 0.2 psi for that 1 hour period. 3.8 Purging. The interior of the telescope shall be purged with dry nitrogen supplied at a pressure of 6.00 0.25 psig until the dew point of th
32、e emergent gas is no higher than -25 F. Purging apparatus shall be removed when the relief valve is reseated and maintains a pressure of 3.0 0.1 psig. 3.9 Optical. 3.9.1 Parallax. The parallax at the center cross of the reticle pattern shall not exceed 0.25 mil when viewing targets between 125 meter
33、s and infinity. 3.9.2 Reticle accuracy. The angular separation between the 0 mil and the 60 mil graduations shall be 60 0.50 mils. 3.9.3 Parallelism of reticle and image. With the telescope oriented as stated in 3.4, the 20 mil horizontal line of the telescope reticle shall be parallel to the image
34、of a leveled horizontal line within 30 minutes of arc. 3.9.4 Resolution. The resolution of the optical axis shall be 5 seconds of arc or less when using an observation telescope of at least 3 power and an entrance pupil of at least 0.4 inches. Resolution consists of detectable line structure and pro
35、per line count in all four meridians. Total spread in focus shift between meridians shall not exceed diopter as measured at the eyepiece. 3.9.5 Cleanliness. The optical system shall meet the cleanliness requirements of MIL-PRF-13830 and there shall be no more than 3 particles of dirt visible on the
36、reticle and the area of such particle shall not be in excess of the area equivalent to a size 10 dig. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-48558C 6 There shall be no dirt within the optical system which interferes with observation
37、or adversely affects image quality. 3.10 Operability. 3.10.1 Torque of diopter adjustment. The running torque required to operate the diopter adjustment shall be within the values specified in Table II at the corresponding temperatures. TABLE II. Diopter adjustment torque. Temperature Torque require
38、d +60F to +90F 5 to 9 inch pounds -50 5F 25 inch pounds maximum +145 5F 25 inch pounds maximum 3.10.2 Attachment. The elbow telescope locking mechanism shall be operable when exposed to the operating temperatures of 3.5.2. The telescope shall be retained in a manner representative of its use on the
39、Mount, Telescope M172A1. 3.11 Reticle illumination. The reticle markings shall be clearly distinguishable when observed in ambient light conditions ranging from dusk into darkness. 3.12 Interchangeability. Telescope interchangeability shall be verified by the insertion, seating, and subsequent remov
40、al of a maximum fit gage. 3.13 Workmanship. Workmanship of the elbow telescope shall be in accordance with the requirements of MIL-F-13926 and MIL-PRF-13830. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-48558C 7 4. VERIFICATION TABLE III.
41、Requirement/verification cross reference matrix. Method of Verification Class of Verification A - First Article B - Conformance 1 - Analysis 2 - Demonstration 3 - Examination 4 - Test Section 3 Requirements Description Verification Method Verification Class Section 4 Verification 1 2 3 4 A B 3.1 Fir
42、st article X X X 4.2 3.2 Conformance X X X 4.3 3.3 Elbow telescope X X X X 4.3.2.4 3.4 Orientation X X X 4.4 3.4.1 Collimation of reticle X X X 4.4.1 3.5.1 Storage temperature X X X 4.5.1 3.5.2 Operating temperature X X X 4.5.2 3.5.3 Shock X X X 4.5.3 3.5.4 Vibration “A” X X 4.5.4 3.5.5 Vibration “B
43、” X X 4.5.5 3.6 Collimation change, post shock and vibration X X X 4.6 3.7 Sealing X X X 4.7 3.8 Purging X X X 4.8 3.9.1 Parallax X X X 4.9.1 3.9.2 Reticle accuracy X X X 4.9.2 3.9.3 Parallelism of reticle and image X X X 4.9.3 3.9.4 Resolution X X X 4.9.4 3.9.5 Cleanliness X X X 4.9.5 3.10.1 Torque
44、 of diopter adjustment X X X 4.10.1 3.10.2 Attachment X X X 4.10.2 3.11 Reticle illumination X X X 4.11 3.12 Interchangeability X X X 4.12 3.13 Workmanship X X X 4.13 4.1 Classification of inspection. The inspection requirements specified herein are classified as follows: a. First article inspection
45、 (see 4.2) Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-48558C 8 b. Conformance inspection (see 4.3) 4.2 First article. When specified, a sample shall be subjected to first article verification in accordance with Table IV. TABLE IV. First
46、article inspection criteria. Examination or Test Requirement Paragraph Verification Paragraph Orientation 3.4 4.4 Collimation of reticle 3.4.1 4.4.1 Storage temperature 3.5.1 4.5.1 Operating temperature 3.5.2 4.5.2 Shock 3.5.3 4.5.3 Vibration “A” 3.5.4 4.5.4 Collimation change, post shock and vibrat
47、ion 3.6 4.6 Sealing 3.7 4.7 Purging 3.8 4.8 Parallax 3.9.1 4.9.1 Reticle accuracy 3.9.2 4.9.2 Parallelism of reticle and image 3.9.3 4.9.3 Resolution 3.9.4 4.9.4 Cleanliness 3.9.5 4.9.5 Torque of diopter adjustment 3.10.1 4.10.1 Attachment 3.10.2 4.10.2 Reticle illumination 3.11 4.11 Interchangeabil
48、ity 3.12 4.12 Workmanship 3.13 4.13 4.2.1 First article quantity. First article inspections shall be performed on three (3) complete units. 4.2.2 First article inspection to be performed. The first article inspection shall be performed in accordance with Table IV. 4.2.3 First article rejection. If any item of the sample fails to comply with any of the first article requirements, the first article shall be rejected. 4.3 Conformance inspection. 4.3.1 Lot formation. Lot formation shall be in accordance with the lot formation requirements of MIL-STD-1916
