Page 54 - 2019 Mil/Aero eBook
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The Mil/Aero Gauntlet of Standards
The military and aerospace markets encompass a wide variety of different applications, including radar, cameras, vehicular electronics, avionics, embedded systems, unmanned aerial vehicles (UAVs), and many others. Connectivity is at the core of all of the applications within these markets, ensuring peak performance and the reliable transmission of power, signal, data, and other media. As such, these applications require high- performance and high-reliability components built to exacting military or aeronautics standards.
These standards address connector characteristics, capabilities, and selection criteria including:
1. The ability to withstand external environment extremes in temperature, pressure, and moisture.
2. Select connector housing materials with the right impact on electrical and mechanical performance.
3. Harmonizing connector specifications with the application environment and performance requirements to avoid the selection or development of an under- or over-qualified connector product.
4. Choosing customized connectors when necessary to address severe size constraints and ease connector integration into challenging systems.
5. Harsh-environment connector characteristics designed to ensure optimal performance in some of the world’s most difficult application areas.
Military and aerospace standards require the strict use of both certain materials and processes. In many cases, the standards are similar; however, military and space flight applications do have some differences in their approach to and considerations for standard connector requirements.
Positronic PCDD Series high-density D-Sub connectors for mil/aero applications are rated for operating temperatures extending from -55°C to 125°C, are qualified to UL #E49351 and CUL #49351, have a UL94 V-0 flammability rating, and are available RoHS 5/6 compliant. They are also available in six layouts with steel or stainless steel shells, polyester insulators, and 15–104 fixed, machined, size 22 gold-plated copper alloy contacts.
Military Specifications
Military connectors were developed in the 1930s for severe aeronautical and tactical service applications. As technology advanced, connectors became smaller and lighter, delivered improved bandwidth and security, and consumed less energy. They also became durable enough to endure sizzling heat, blustery winds, freezing temperatures, watery depths, chemical exposure, intense shock and vibration, varying pressure, and other environmental hazards.
Some of the most popular connectors that meet military specifications are D-Subminiature (D-Sub) connectors, which are often sold under the part prefix “M24308” to indicate that they satisfy MIL-DTL-24308 standard requirements. The specifications under this standard cover everything from connector materials to manufacturing processes and performance. Examples include mandating the use of statistical process control techniques in the manufacturing process, the use of high-grade, corrosion resistant metal materials or other robust materials treated to resist corrosion, and the use of specific plating materials and contact finishes. Plating options may,

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