For example, the inherent ruggedness of 38999 can potentially make these connectors too heavy for use on weight-critical airframes. This issue can be mitigated by using lighter, lower-cost composite material connector shells, which can reduce the weight of an assembled connector by 20%. Individually that doesn’t seem like much, but large aircraft can use many hundreds of connectors, and the weight savings add up. Composite connectors are gaining wider market acceptance due to the balance between light weight and rugged duty performance. The physical properties of the 38999 connector can also be a challenge for data transfer. Standard design 38999 connectors will provide good 1 Gb/s signal transfer. However, modern designs for small multipin, segmented connectors, and high signal density connectors can provide 10 Gb/s and fit within 38999 shell sizes. These high- density connectors, by virtue of their design, will outperform standard 38999 connectors in harsh environment applications which require very high data transfer rates. REPAIRABILITY The repairability features of a connector are every bit as important as the performance ratings. Connectors must have the capability for rapid repair and quick return to service in applications such as passenger planes that fly on tight schedules; delays or service interruptions are unacceptable due to their cascading effect and the subsequent high financial impact. RUGGED-DUTY PERFORMANCE WITH
to manufacturer. Some connector and wire assemblies are not field repairable and require the complete replacement of a cable assembly. The affected cable assembly is returned to the factory for repair, or a spare cable assembly is installed to keep the affected system up and running. This makes sense for some defense articles where field repair is not practical and removal and replacement can be accomplished quickly. Complete replacement is not a good option for industrial or commercial aircraft applications in which accessibility is difficult or the length of cable assemblies makes it impractical. The most effective solution, in that case, is field-repairable connectors that can be serviced by technicians on-site. Field-repairable connectors employ various service methods. Several manufacturers require special service parts and special tools to accomplish repairs. The most practical solution is a connector that can be repaired with commonly available avionics indent crimp service tools and AS39029 contacts. An unusual but critically important consideration for repairable connectors is whether the connector requires a heat gun for shrink tubing or curing of potting materials. Prior to making any repair to a passenger aircraft requiring heat or a flame source, passengers must deplane, and the aircraft must be towed to a fire-safe area with firefighting equipment on standby. A simple repair for a connector, therefore, can become very complicated and take many hours, removing the aircraft from service for extended periods. Crimp connectors assembled with common avionics hand tools eliminate the complexities of fire-safe repairs.
Within the industry, the repair schemes are not entirely standard and can vary from manufacturer
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