The highly advanced military aircraft of today, such as the Lockheed Martin F-35 fighter or Boeing B-1 bomber, contain a large amount of specialized electrical equipment. Some examples include relay panels, circuit breaker panels, mux transformer panels, audio panels, navigation computers, weapons computers, and many more. This equipment is essential in enabling the aircraft to complete its designed mission, so it must be able to communicate with each other as well as with the pilot.
Electrical wiring harnesses are installed in the aircraft to connect all of the equipment to each other, the pilot, and the airframe. Each one of these harnesses contains a varying number of connectors, and each connector can contain anywhere from one to over one hundred wires. In order to understand what an insert arrangement is and why it is needed, let’s break down the three basic components of a modern military circular connector.
1. Contacts – Placed on the end of each wire and held in place with a crimp or solder. Typically made of highly-conductive gold plated copper.
2. Insert – This holds all of the contacts in a specific orientation for correct mating and insulates them from one another. Typically made of reinforced epoxy resin or other composite material.
3. Outer shell – The enclosure that holds the insert and contacts. Typically made of die-cast aluminum and plated or anodized for corrosion protection.
In order for the connector to mate up with another component the contacts must be held in place in a specific orientation so that they are not damaged when the components are connected together. The specific orientation of the contacts is known as the insert arrangement. If you were to open up the latest Amphenol or TE Connectivity catalog you would see many different variations of insert arrangements for a given connector size in order to facilitate the one to over one hundred wires that may be present.
Click here to see a great image of a connector’s insert arrangement and the proprietary pin out aid that InterConnect Wiring’s top engineers designed.