1、Fs/-ab MIL-A-5999B( USAF) 12 October 1973 SUPERSEDING 30 April 1958 MILA- 5 999A( USAF) MILITARY SPECIFICATION ANTENNA SUBSYSTEM FOR AIRCRAFT MARKER BEACON EQUIPMENT GENERAL SPECIFICATION FOR. 1. SCOPE 1.1 test requirements for an antenna subsystem used with VHF marker beacon equipment in the spot f
2、requency of 75 MHz. This specification covers the general design, performance, and flight 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 specified herein. SPECIFICATIO
3、NS Feder al LP-383 Plastic Material , Polyester Resin, Glass Fiber Base , Low Pressure Laminated Mi lit ary MIL-E-5400 MIL-E-O MIL-C- 4 5 662 t Electronic Equipment, Airborne, General Specification For Electromagnetic Compatibility Requirements , Systems Calibration System Requirements FSC 5826 A Pr
4、ovided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-A-5777B 5ii W 7777706 0348023 O U MIL-A-5999B( USAI?) STANDARDS Military MI L-S TD- 4 90 MIL-STD- 810 Environmental Test Methods MIL-STD-831 MIL-STD- 877 Specification Practices Test Reports , Prepara
5、tion of Antenna Subsystems, Airborne, Criteria For Design and Location of (Copies of specifications , standards, drawings , and publications required by suppliers in connection with specific procurement functions should be obtained from the procuring activity or as directed by the contracting office
6、r.) 3. REQUIREMENTS 3.1 First article inspection. This specification makes provisions for first article inspection. 3.2 General documents. The requirements of MIL-STD-877 apply as requirements of this specification. The requirements of MIL-E-5400 apply to antenna components containing electronic cir
7、cuitry. When the general documents conflict with this specification, this specification shall govern. 3.3 Design and construction. The antenna subsystem specified herein shall be designed to be compatible with the VHF marker beacon requirements for the weapon system under consideration. The antenna
8、subsystem may be a separate item or may be installed as an integral part of the aircraft. The mtenna subsystem may be in physical combination with other frequency range antenna subsystems, thus serving two or more equipments. If the antenna subsystem is made in combination with other antenna subsyst
9、ems, it shall be possible to operate the equipments simultaneously, and with no interference, one with another. 3.3.1 Antenna subsystem composition. The antenna subsystem shall include all components, such as receiving elements , transmission line , matching devices, filters, and switching devices,
10、that are connected in the system beyond the output connector of the associated equipment. 3.3.1.1 Antenna receiving elements. The antenna receiving elements shall consist of cavity, dipole, array, or other elements suitable for installation in the aircraft weapon system consistent with the position
11、in which it is to be installed. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-A-5939B 58 979790b 0148024 2 7 3.3.1.2 Transmission line and connectors. The antenna subsystem shall be so designed and installed that connection can be readily mad
12、e to the associated radio equipment through a minimm length of radio-frequency cable. R-f cable and associated connectors shall be subject to prior approval by the procuring activity. antenna element and the r-f cable shall satisfy the environmental requirements specified herein. The maximum allowab
13、le loss between the receiver and antenna element shall not exceed 2 dB. The use of standard cables and connectors shall in no way be construed as justification for exceeding the maximum allowable attenuation stated herein. The method used in effecting electrical connection between the 3.3.1.3 Struct
14、ural plastic materials. The requirements for type II materials of L-P-383 shall apply for all structural plastic materials used in the antenna subsystem covered by this specification. 3.3.2 Flush antenna designs. with the skin shall be designed for a given aircraft location only when standard curved
15、 shapes are not applicable. Flush antennas of special curvature to mate 3.3.2.1 shall not be used-to obtain a mating surface with the aircraf% skin. Plastic cover plates, not an integral part of the flush antenna, 3.3.3 Aerodynamics 3.3.3.1 elements into the airstream when installed on the aircraft,
16、 shall be minimized by proper shape design. 3.4 Performance The total aerodynamic drag, resulting from the protrusion of antenna 3.4.1 Electrical requirements 3.4.1.1 Frequency. spot frequency of 75 MHz. 3.4.1.2 Polarization. When properly installed on an aircraft, the antenna subsystem shall receiv
17、e signals from directly beneath the aircraft that are polarized parallel to the fore and aft axis of the aircraft. 3.4.2.3 VoXtage standing wave ratic (VSWR). The antenna subsystem shall be so designed and installed that the VSW produced on any part of the interconnecting radio frequency transmissio
18、n line shall not exceed 1.5 : 1 at 75 MHz With reference to a nominal 50-ohm level. shall be maintained within a 5:i VSWR circle with the antenna fixed tuned. When subjected to extreme service conditions, the antenna subsystem shall not go beyond 2.5 :1 VSWR at 75 MHz. The antenna subsystem shall be
19、 designed to cover the A bandwidth of 300 kHz 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-A-5777B 58 777770b 0348025 4 m 3.4.1.4 Efficiency. The minimum acceptable sensitivity in voltage of the antenna subsystem shall be within 10.5 dB of t
20、hat of a half-wave dipole at a freqi*ency of 75 MHz. 3.4.1.5 Radiation pattern requirements. The radiation pattern shall be essentially a lobe without deep nulls so that the maximum gain of the antenna subsystem is downward from the aircrart and in a direction not more than 10 degrees from a vertica
21、l line through the antenna subsystem. All external store configurations that are proposed or normally carried operationally shall be consi dered separately. 3.4.1.6 Interference acceptability level. The interference of other electronic equipment with the antenna subsystem operating with the marker b
22、eacon receiving set shall be considered to be at an acceptable low level when the operation of other electronic equipment in the aircraft does not give.erroneous marker indication throughout the flight profiles specified in section 4 herein. 3.4.2 Environmental conditions. Unless otherwise specified
23、 for a particular weapon system, the antenna subsystem, including all components thereof, shall withstand the environmental requirements defined under 4.4.3.3 without reducing the performance below the limits specified herein. In addition to the environmental conditions specified above, the antenna
24、subsystem shall be designed and constructed to withstand the severest environmental conditions existing in the area of the aircraft in which it is installed. Vibration, shock, extreme temperatures, effects of gunfire or other armament originating within the aircraft or resulting from flight conditio
25、ns shall be taken into consi derati on. 3.4.3 Flight profile performance. When installed on the aircraft, the antenna subsystem shall satisfactorily perform the flight profile executions specified in section 4 herein. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without lic
26、ense from IHS-,-,-3.4.3.1 Range. In a horizontal flight of the aircraft over the ground station cone of silence marker at 10,000 and 30,000 feet altitude (ground clearance), a position marker beacon indication shall be received for a distance of not less than 1 mile. 3.4.3.2 Pattern symmetry. In hor
27、izontal flight over the ground station at any altitude, the duration in miles of marker indication, when approaching a point directly over the ground station, shall not be more than 50 percent greater than the duration in miles of marker beacon indication when leaving the point directly over the gro
28、und station, and vice versa, (section 4) ) . (Mathematically this may be expressed as 0.67 lier shall perform calibration tests on all VHF marker beacon equipment Calibration of marker beacon equipment. Prior to beginning any tests in accordance with the supplier-prepared test plan conforming to the
29、 requirements of MIL-C-45662. Records of all test results shall be maintained. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-A-5999B 58 = 7979906 0348027 8 4.3.2 receiver shell be tested and adjusted within the limits of the bench and preflig
30、ht procedures specified in the applicable bench, preflight, and flight test specification to be furnished by the procuring activity. sensitivity shall be measured and recorded before each series of tests. The preflight procedures shall be conducted after the installation test of Marker beacon receiv
31、er bench and preflight tests. The marker beacon The receiver 4.3.3. 4.3.3 properly installed in the aircraft and connected in accordance with the installation wiring diagram and installation specification to be furnished by the procuring activity. An operational installation test shall be performed
32、on the VHF marker beacon system, including cables and antennas. 4.3.4 Ground test station. standard Federal Aviation Administration (FU) cone of silence transmitter as maintained and operated by the FU of the Department of Transportation. grovrid test station for flight testing under the marker beac
33、on antenna subsystem shall be similar to the station used under operational conditions. L.4 First article inspections 4.4.1 First article samples. The first article samples shall consist of models of all major components of the antenna subsystem representative of the production equipment and covered
34、 by the antenna sybsystem component specification required in 4.7.1. under the test conditions specified herein and at the point designated by the contract. Aircraft installation test. The VHF marker beacon equipment shall be The ground equipment shall consist of a The The first article samples shal
35、l be tested 4.4.1.1 Tesking instructions. Unless otherwise specified in the contract or purchase order, FI. minimum of three first article samples shall be required and testing shall be as follows: a. specified under 4.4.3.3. One first article sample shall be subjected to the environmental tests b.
36、One first article antenna subsystem shall be installed on the test aircraft and subjected to the flight tests specified under 4.4.3.4. c. One first article sample shall be subjected to the electrical tests specified in 4.4.3.2. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted w
37、ithout license from IHS-,-,-MIL-A-57978 5 7797906 0148028 T m MI L-A-59 99 B (USAI? ) 4.4.2 Scale models, A scale model of the antenna or antenna subsystem installed on a scale model of the aircraft involved shall be used for radiation pattern measurement( see 4.4.3.1). Modeling details such as exte
38、rnd stores , canopy constructions , flaps , wheel doors , et cetera shall be similar enough to full-scale details to permit reasonably accurate radiation patterns to be measured. The type of construction and metallic surfacing wed shall permit maximum versatility for testing new locations for antenn
39、as. by more than 2 percent from the correct dimension, or one-sixteenth inch, whichever is greater. Reduced scale dimensions of the model shall not differ 4.4.3 First article tests 4.4.3.1 Radiation pattern measurement tests. Radiation patterns (see 3.4.1.5) of the antenna or antenna subsystem in th
40、e locations proposed by the supplier shall be obtained by scale model techniques. set of patterns shall be submitted for each selected antenna location. isotropic gain shall be computed and plotted on each pattern chart for each antenna subsystem measured. The model frequency shall be chosen to simu
41、late 75 MHz. All other antennas in the imediate vicinity of the model antenna under test shall be installed and properly terminated to insure that normal coupling effects will be reflected into the pattern data. A complete integral The 4.4.3.2 Electrical tests. The procedures and application of elec
42、trical tests to determine proper performance and compliance with the requirements of this specification shall be prepared by the supplier and subject to approval by the procuring activity. 4.4.3.3 Environmental tests 4.4.3.3.1 accordance with the indicated methods of MIL-STD-810. The procedures may
43、be modified as necessary to be compatible with the expected extreme conditions: The following environmental testing shall be conducted in a. Temperature shock, method 503, procedure I b . class of applicable detail specification Temperature-altitude , method 504 , procedure I, table 504-1 , equipmen
44、t c. Humidity, method 507, procedure I 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-A-5777B 58 W 7777706 0348027 1 MIL-A-5999B (USAF) d. e. of the applicable detail specification. Salt fog, method 509, procedure I Vibration , method 514.1 ,
45、 equipment lY category and specific requirements f. Shock, method 516.1, procedure I, figure 516.1-2, shock parmeters (a) and (c). g. Gunfire vibration, nethod 519.1, procedure as applicable. 4.4.3.3.2 Immersion (leakage) tests. suitable ligui such as boiled ethylene glycol or water. shall be uncont
46、rolled if the supply temperature is between llC and 2OoC (51.8OF to 68OF). be reduced to approximately 1 inch of mercury and maintained for 1 minute, or until bubbles substantially cease to be given off by the liquid, whichever is the longer. The absolute pressure shall then be increased to 24 inche
47、s of mercury. Any bubbles coming from within the equipment case shall be considered as leakage. exterior parts of the case shall not be considered as leaks. A helium leak detector or other means of test, equal or superior in sensitivity to the immersion test method described above, may be used upon
48、approval by the procuring activity. 4.4.3.3.2.1 of the antenna subsystem that are gasket sealed, pressurized, or fusion sealed. Components that are not sealed or pressurized shall be subjected to a humidity test (4.4.3.3.1) in lieu of the immersion test, The equipment shall be immersed in a The wate
49、r temperature The absolute pressure of the air above the liquid shall then Bubbles which are the result of entrapped air on the various The test specified in 4.4.3.3.2 shall apply to all components 4.4.3.4 Flight tests 4.4.3.4.1 Test setup a. The VHF marker beacon flight test aircraft shall be one of the first 10 assembled models of the weapon system under test. 8 Provided by IHSNot for ResaleNo reproduction or networking permitted
