AP which is a pressure-sealed single-slot flush-mounted broadband airborne antenna.

Pages 1 - 2 - 3 - 4 - 5 - 6

MIL-DTL-25895A

2.2.2 Other Government documents, drawings, and publications. The following other Government documents,

drawings, and publications form a part of this document to the extent specified herein. Unless otherwise specified,

the issues of these documents are those cited in the solicitation or contract.

DRAWINGS

U. S. AIR FORCE

56D13026

Antenna AT-505/AP, Assembly of.

(Copies of these documents are available on line at William.Dodd@wpafb.af.mil or from the Aeronautical Systems

Center, 88 OSS/OSE, Bldg 280 Door 4, 4170 Hebble Creek Rd., Wright-Patterson AFB, OH 45433-5653.)

3. REQUIREMENTS

3.1 Preproduction. This specification makes provisions for preproduction testing.

3.2 General specification. The requirements of MIL-E-5400 for class 2 equipment apply as requirements of this

specification with the exceptions and additions called out herein. When the two specifications conflict, this

specification shall govern.

3.2.1 Soldering. Cleaning flux, such as sal amoniac, shall not be used. Alcohol may be used for cleaning after

tinning and soldering. All rosin deposits shall be removed. Mechanical loads shall not be imposed on soldered

connections. Soldering shall meet all the requirements of accepted industry standards.

3.3 Design and construction. The design and construction of the antenna shall have the dimensions and general

features shown on Drawing 56D13026.

3.3.1 RF connectors - The RF connector included as a part of the antenna assembly covered by this specification

shall be UG-680/U or equivalent and shall be in accordance with MIL-PRF-39012.

3.3.2 RF cable. The RF cable included as a part of the antenna assembly covered by this specification shall be

RG-141/U and shall be in accordance with MIL-DTL-17.

3.3.3 Antenna interior. The antenna shall be filled with gas-expanded foamed plastic similar to NOPCO Lockfoam

with a 6-pound density. This is a closed cell type with a power factor of approximately 0.002 and dielectric constant

of 1.13.

3.3.4 Antenna window. The antenna window shall be of laminated glass-cloth material in accordance with

MIL-I-24768/1.

3.3.5 Mechanical.

3.3.5.1 Pressure-sealed construction. The antenna shall be sealed at all points so that moisture cannot leak into

the interior when subjected to the immersion tests specified in 4.2.5.

3.3.5.2 Pressure-tight mounting flange. The mounting flange of the antenna shall be constructed for mounting in

an opening in the skin of an aircraft. Its purpose shall be to effectively prevent the escape of air from a pressurized

aircraft at this point.

3.3.6 Pure tin. The use of pure tin as an underplate or final finish is prohibited both internally and externally. Tin

content of the antenna components and solder shall not exceed 97 percent, by mass. Tin shall be alloyed with a

minimum of 3 percent lead, by mass (see 6.4).

3.4 Performance.

3.4.1 Voltage Standing Wave Ratio (VSWR). At all frequencies between 400 MHz and 480 MHz, the VSWR shall

be equal to or less than 2.0 to 1.0 when measured on a 50-ohm transmission line feeding the antenna.