1、MIL-1-21400 (AER) 2 JUNE 1958 MILITARY SPE CIFICATION INTERVALOMETER, ORDNANCE, RELEASE TD- 239/A This specification has been approved by the Bureau of Aeronautics, Department of the Navy. 1. SCOPE 1. 1 The equipment covered by this specification shall generate/pulses, recurring at precise intervals
2、 of time, which are suitable for direct operation of release solenoids of bomb racks and other store suspension equipment. This equipment shall be such that the use of tables, or graphs, isunnecessary to provide the proper time interval associated with a desired ground spacing between dropped stores
3、 when the aircraft ground speed is manually inserted, The inter- valometer shall also control the number of stores expended. a. APPLICABLE DOCUMENTS 2.1 General - The foliowing documents of the issue in effect on the date of invitation for bids, form a part of this specification. SPEC1 FICATIONS Mil
4、itary MIL-C-172 Cases; Bases, Mounting; and Mounts, Vibration (For use with Electronic Equipment in Aircraft) Crystal Units, Quartz MIL- C- 3098 MIL-E-4682 Electron Tubes, Choice and Application of MIL-W-5088 Wiring, Aircraft, Installation of MIL-E-5400 Electronic Equipment, Aircraft, General Specif
5、ication for MIL-E-5422 MIL- I- 61 81 Environmental, Testing, Aircraft Electronic Equipment Interference Limits; Tests and Design Requirements, Aircraft Electrical and Electronic Equipment MIL-C-6781 MIL-P-7788 MIL- E- 7894 Control Panel; Aircraft Equipment, Rack or Console Mounted Plate, Plastic, Co
6、ckpit and Interior Controls Lighting Electric Power, Aircraft Characteristics of 1 f Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-I-21LI00 12 M 9799906 0301306 O W. MIL-I- 21400(Aer) MIL- P- 17555 Preparation for Delivery of Electronic Equipme
7、nt; Miscellaneous Electrical Equipment (Except Rotating Electrical Equipment) and Associated Repair Parts MIL- T-18303 Test Procedures, Preproduction and Inspection for Aircraft Electronic Equipment; Format for MIL-N-18307 Nomenclature and Nameplates for Airborne Electronic and Associated Equipment
8、Bureau of Aeronautics SAR-300 Engineering Change Proposais, Electronic Material Changes and Electronic Material Bulletins; Prepara- tion of STANDARDS Military MS-25245 Connections - Input Power Airborne Electronic Equip- ment 28-Volt DC, 115-Volt Single-phase AC, and/or 115/200-Volt Three-phase AC,
9、or Combinations DRAWINGS Bureau of Aeronautics 58A163D1 58A163DB TD- .239/A Intervalometer, Ordnance Release General Arrangement TD- 239/A Intervalometer, Ordnance Release In- stallation 58A16353 TD- 239/A Intervalometer, Ordnance Release Schematic Wiring 2. 2 Availability of Documents: (1) Give bot
10、h the title and number when requesting specifications, standards, drawings, and publications. All requests should be made via the cognizant Inspector of Naval Material or Bureau of Aeronautics Representative. (2) Copies of this specification and applicable documents maymbe obtained upon application
11、to the Commanding Officer, Naval Aviation Supply Depot, (AD), 700 Robbins Avenue, Philadelphia 11, Pennsylvania. (3) Copies of applicable drawings may be obtained upon application to the Bureau of Aeronautics, Navy Department, Washington 25, D. C., Attention: Avionics Division. 2 Provided by IHSNot
12、for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-1-21400 12 m 9797906 0301307 2 M - MIL-I -21400(Aer) 2.3 Precedence - When the requirements of the contract, this specification, or applicable subsidiary specifications are in conflict, the following precedence shail
13、apply: (1) Contract - The contract shall have precedence over any specification. (2) This Specification - This specification shall have precedence over all applicable subsidiary specifications. Any deviation from this specification, or from subsidiary specifications where applicable, shall be approv
14、ed in writing by the Bureau of Aeronautics. (3) Referenced Specifications - Any referenced specification shall have pre- cedence over all applicable subsidiary specifications referenced therein. All referenced specifications shail apply to the extent specified, 3. REQUIREMENTS 3.1 Parts and Material
15、s - in the selection of parts and materiais, fulfillment of major design objectives shall be the prime consideration. In so doing the following shall govern: (1) Parts and materials as approved by Specification MIL-E-5400 shall be given first consideration, (2) When the characteristics of standard M
16、a parts and materiais are such that their use will not fulfill the requirements because of size, weight, performance or other reasons, materials and parts shall be used which most nearly meet or exceed the requirements of the respective standard parts and material specifications. (3) When a nonstand
17、ard part is used, the meeting of general material require- ments such as noninfiammability, fungus resistance, nonintoxic, etc. , and the meeting of environmental conditions as required by Specifications MIL-E-5400 or MIL-E-5422 shall be of prime consideration. (4) in the selection of parts, the abo
18、ve considerations shall apply if the assembly is to be built for detail part maintenance. in the event the entire assembly is to be built to be expended, th9 assembly shall be constructed and the quality of the individual parts shall be such that the unit as a whole will pass material, electrical an
19、d environmental tests. Any assembly built to be expended shail be approved first by the Bureau of Aeronautics. 3.1.1 Nonstandard Parts and Material Approval - Approval for the use of nonstandard parts and materials shall be obtained as outlined in Specification MIL-E-5400 except as follows: (1) Mech
20、anical parts shall be submitted as nonstandard parts only when the material requirements of Specification MIL-E-5400 are not met. (2) Nonstandard parts of an electrical nature as defined in Specification MIL-E-5400, must be approved before the preproduction model of the equipment is submitted for te
21、sts. The request for approval shall be forwarded to the Bureau of Aeronautics before the part is purchased or fabricated. in addition to or lieu of the Nonstandard Part Data Sheet, the contractor shall submit an itemized list of the parts, their sources, and the contractors drawing or purchase speci
22、fication covering the parts, 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL- I - 21400(Aer) 3.1. 2 Tube Types - The choice and application of electron tubes used in the equip- ment shall be in accordance with the following requirements and in
23、the sequence noted: (1) MIL-E-4682 (2) The use of any tube not meeting the requirements of (1) above shall be approved by the Bureau of Aeronautics; however, before consider- ation for approval, the contractor shall submit the following information: (a) Quantitative data on the electrical advantages
24、 and mechanical adequacy of the proposed tube over the most nearly equivalent type on the acceptable listings. (b) Test data and performance limits of the tube which must be maintained to insure satisfactory and reliable performance in the equipment. (c) Information as to whether the tube manufactur
25、er has received Military or Navy qualification approval for the particular tube. 3.1. 2.1 Electron Tube Complement - A tube complement report shall be prepared in accordance with Specification MIL-E-4682 and submitted to the Bureau of Aeronautics for re- view and approval prior to preproduction test
26、ing. The tube complement shall include all electron tube types (including crystal diodes and transistors) used in the equipment. 3.1. 2. 2 Crystal Units - The choice and application of crystal units used in the equip- ment shall be in accordance with Specification MIL-C-3098. the requirements of MIL
27、-C-3098 must be approved by the Bureau of Aeronautics and information similar tothat required by 3.1. 2 (2) (a), (b), and (c) shall be furnished. The use of any crystal not meeting 3.1.3 Performance Objectives - Minimum size and weight, simplicity of operation, ease of maintenance, and an improvemen
28、t in the performance and reliability of the specific functions beyond the requirements of this specification are objectives which shall be considered in the pro- duction of this equipment. Where it appears a substantial reduction in size and weight or improve- ment in simplicity of design, performan
29、ce, ease of maintenance or reliability will result from the use of materials, parts and processes other than those specified in Specification MIL-E-5400, it is desired their use be investigated. When investigation shows advantages can be realized, a re- quest for approval shall be submitted to the B
30、ureau of Aeronautics for consideration. Each request shall be accompanied by complete supporting information. 3. 2 .Design and Construction 3. 2.1 General - This equipment shall fulfill all applicable design and construction requirements of Specification MIL-E-5400 unless otherwise specified herein.
31、 3. 2. a Service Conditions - The equipment shall operate satisfactorily under any of the environmental and mechanical service conditions or reasonable combination of these con- ditions as specified in Specification MIL-E-5400 for Class 2 equipment. 3. 2.3 Standard Conditions - The following conditi
32、ons shall be used as a basis to establish normal performance requirements and for making laboratory bench tests on the equip- ment: Temperatur e Altitude Vibration Room ambient (30C f 10C) Normal ground None Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IH
33、S-,-,- MIL-Z -21400(Aer) 3.2.4 Total Weight - The total weight of the equipment, excluding cables, shall be a minimum consistent with good design and shall not exceed 8 pounds. 3. 2.5 Operational Stability - The equipment shall operate with optimum perform- ance for 100 hours, continuously or interm
34、ittently, without the necessity ?or readjustment of any controls which are inaccessible during flight. 3. 2.6 Operating Life 3. 2.6.1 Reliable Installed Operating Life - The equipment shall have a reliable installed operating life of at least 1000 hours without removal for bench servicing. Parts req
35、uiring servicing or replacement at the end of this interval ta renew this service life shall be specified by the manufacturer. 3. 2.6. 2 Total Installed Operating Life - The equipment shall have a minimum total operating life of six years with reasonable servicing and replacement of parts. Parts req
36、uiring replacement within this interval and the life of such parts shall be specified by the manufacturer. 3. 2.7 Interconnection Cabling - This equipment shall be capable of satisfactory operation using external wiring in accordance with the applicable requirements of Specification MIL,-W-5088. The
37、 external wiring shall be unshielded, except that a minimum number of the individual wires may be shielded when demonstrated as necessary to meet interference control requirements and provided the assembly of the cable to its plugs may be easily accomplished. 3. 2. 8 Cables and Connectors - The equi
38、pment shall provide for the use of cables and connectors in accordance with Specification MIL-E-5400. Hawever, external cables and that portion of the connectors attached to the cables shall not be supplied as part o? the equipment. 3.2.9 Console Controls - The equipment shall be satisfactory for mo
39、unting in a console arrangement when used in aircraft. This equipment shall meet the applicable require- ments of Specification MIL-C-6781 and shall have a plastic lighting plate conforming to Specifi- cation MIL-P-7788. The lamps shall be connected in parallel with one side grounded to the chassis
40、of the unit and the other side connected to a separate contact, in the electrica connector recep- tacle of the unit, for connection to an externali 28-volt input lead. The brilliance. o? the lamps will be controlled externally and the brilliance control shall not be part of this equipment. The arran
41、gement of controls and all lettering and markings proposed for use on the front panel of the equipment shall be approved by the Bureau of Aeronautics prior to fabrication of any complete units. All diai settings shall be direct reading (e. g: 0475 yards) 3. 2.10 Input Power Requirements - The equipm
42、ent shall meet all applicable require- ments of Specification MIL-E-7894 and shall give specified performance from the following power source with characteristics as defined in Specification MIL,-E-7894 having limits as specified hereinafter. The power required shall not exceed the specified amount:
43、 (1) DC power 28-volt system Operating voltage limits 24 to 30 volts 24 to 30 volts 15 amps into a 2.5 mh inductive load intermittant for firing an ex- ternal load, plus 2 amps continuous Reduced performance voltage limits Current 5 Provided by IHSNot for ResaleNo reproduction or networking permitte
44、d without license from IHS-,-,-* flIL-I-2L4OO 12 I 7777706 030L3LO 2 I- MIL-I -21400(Aerl 3.2.11 Input Power Connection - input power connections shall be in accordance with MS 25245. 3. 2.12 Overload Protection - Overload protection for the equipment shail be pro- vided in the equipment. All parts
45、and circuits of the equipment which are likely to carry an over- load due to any failures orpoor adjustments shall have suitable protection devices or shall be proportioned to withstand such overload without permanent damage to the equipment, The use of fuses and other protective devices shall be he
46、ld to a minimum. below the minimum specified herein and shall automatically resume normal operation when the voltage returns within limits. 3.2.12.1 Undervoltage Protection - The equipment shall not be damaged by voltages 3.2.13 Standby Provisions - The equipment shall provide for a standby position
47、 wherein rated voltage shall be applied to all tube filaments. Except for the associated filament circuits, voltages shall not be applied to other parts of the equipment. . 3.2.14 Nomenclature and Nameplates - Nomenclature assignment and nameplate approval for equipment identification shall be in ac
48、cordance with the requirements of Specification MIL- N- 18307. 3.2.15 Interchangeability - The interchangeability requirements between like assemblies, subassemblies and replaceable parts as specified in Specification MIL-E-5400 shall be extended to require interchangeability of units of this equipm
49、ent with the latest model of any previously produced equipment. Such interchangeability shall be measured against a model, manufacturing drawings, or other technical information as provided by the Bureau of Aeronautics for the purpose. in the event that requirements of Specification MiL-E-5400 conflict with the requirements for interchangeability, the interchangeability requirements shall govern. 3. 2.16 Maintenance Provisions and Field Testing - Provisions for maintenance shall be
