ROI Wiring is a modular, organized wiring system developed for aircraft applications using standard wiring components by Raytheon 11S.

Weight Reduction

• No need for individual shields and jackets for internal harness electrical interference control (cross-talk)
• Using less outer gross shield/foot of harness for external EMI/EMC control (when necessary) due to smaller harness cross-section of ROI harnesses
• Eliminating or reducing the number of shield-terminating grounding devices
• The shared tensile strength of wires in a woven ribbon format can be exploited by using a smaller minimum wire gauge for select circuits.

Components & Weight

• ROI controls crosstalk without using heavy individually shielded twisted cables that also are labor intensive to terminate
• ROI uses component wires in woven ribbons
• The absence of shields/jackets on circuits saves significant weight all throughout the aircraft
• ROI works with virtually all common aircraft connectors, both old and new equipment, and standard wiring tools because the ribbons use standard stranded mil-spec wire.

ROI Applications

• ROI, a “successful” organized wiring concept, was developed to satisfy engineering, logistics, and maintenance requirements for wiring for U.S. Military & Aircraft
• Designed into and flying on UH-1Y, AH-12, Bell 609, A-60 Intruder as well as V-22 Osprey
• Flight tested in Boeing JSF Demo aircraft flight control system
• ROI wiring can retrofit into existing aircraft

ROI System Architecture

• Due to increased modularity, ROI designs use a higher number of harnesses than conventional design approaches
• The V-22 has shown that it can be less expensive to produce a larger number of
  simple ROI harnesses than a smaller number of conventional harnesses
• To max the use of ribbonized technology, ROI harnesses have fewer branches than conventional harnesses
• Circuits are grouped more by “destination” than by system and are carried in Trunk-line harnesses from area to area
• Endpoint harnesses, also ribbonized, connect trunk-lines to multiple boxes in a particular bay or area
• Complex transitions can require junction boxes
• New ROI harnessing techniques reduce the need for junction boxes in the architecture design

Wiring Diagnostics & Repair

• The orderly arrangement of wires in ROI harnesses provide a consistent electrical cross-section
• This consistency lends itself to diagnostic processes such as TOR, FDR, Standing Wave, etc., by reducing reflections
• Standard “buzzing out” methods of troubleshooting ROI harnesses is easier than conventional wiring

Damage and Repair

• Tests performed at the Navy’s China Lake facility show that ROI harnesses sustain less damage than conventional wiring harnesses from small arms and cannon fire (30cal, 50cal, and 23mm)
• ROI enhances speed and accuracy of damage assessment from battle damage or damage from other mechanical means
• Damaged ribbons can be rapidly repaired using standard wire crimp splices
• Many “peace time” mishaps, such as damage caused by drilling errors, benefit from the rapid repair-ability as well.

Manufacturing Cost Savings

• No need for costly harness form boards since ROI harnesses can be built on a benchtop.
• No need for shield terminators.
• No need for unique circuit identification to be marked on each wire. ROI uses standard pre-marked ribbons.
• No need for costly machine braiding – ROI uses slip-on gross shielding and jackets.
• ROI can use semi or fully automated stripping and crimping machines.

Shield Splitters

• Raytheon Shield Splitters are available in both
  90° and 180° types in four diameters (works
  with round bundles and ROI ribbon harnesses)
• Utilizes slipover braid providing mechanical
  harness splitting without soldering or machine
  braiding eliminating or reducing the need for
  many wiring integration units (WIUs)
• Finished harness provides 360° EMI shielding

ROI Testing

• Testing has been conducted by Bell, Boeing, the Navy, NASA, and RTSC Indianapolis to verify ROI wiring behavior in the following areas:
  • Electromagnetic Environmental Effects (E3) – Shielding Effectiveness, Circuit Cross-talk, Lightning
  • Heat (Power) Dissipation qualities
  • Simulated Battle Damage Assessment
  • Harness Flex Testing
  • Flight Control System Functionality
• Testing has not indicated any abnormalities or deficiencies in the E3 or other performance parameters of ROI harness configurations

AIRCRAFT WIRING SYSTEM WEIGHT – AN EXAMPLE