The Legacy Avionics Design Process


A typical aircraft completion contains over one hundred thousand components, accessories, wires and terminations. Information for each of these items are manually researched, drafted onto a wiring diagram, and then re-keyed into Excel (TM) spreadsheets so that the data can be managed and used by the other departments. Managing this information is challenging, for even the most experienced organizations.  It is also prone to errors, very labor intensive and costly.

The process used today for installing aircraft electrical systems is very labor intensive. It requires extensive research, coordination and communication between the engineering, manufacturing and procurement teams. Today each process is a manual effort, one that is continuously repeated throughout the life cycle and susceptible to human mistakes.

A typical aircraft completion contains over one hundred thousand components, accessories, wires and terminations. Information for each of these items are manually researched, drafted onto a wiring diagram, and then re-keyed into ExcelTM spreadsheets so that the data can be managed and used by the other departments. Managing this information is challenging, for even the most experienced organizations. The electrical engineers create aircraft wiring diagrams that are used by manufacturing to install the electrical systems into the aircraft.

Historically the tool of choice for creating these wiring diagrams has been AutoCADTM, a generic mechanical drafting program. Because AutoCADTM is intended for mechanical drafting it lacks automation and other features relative to electrical systems design. The engineer has to literally draw every component, wire and attribute onto the drawing. The process is repeated for every instance of that component and wire on every drawing.

Every component used on the wiring diagrams requires an extensive amount of research to ensure its compatibility and technical specifications. This research is performed by the engineer and requires a significant amount of their time, often as many as several hours for a typical piece of equipment. Once this information is obtained the engineer will make their notes for that component and then proceed with their work. It is not uncommon to have multiple engineers simultaneously searching for the same information. This research is continuously repeated for every piece of equipment on every project.

This legacy approach lacks any type of centralized tool built into AutoCADTM or other generic CAD applications to handle this process of “gathering and sharing”. This leads to one of your most expensive resources, avionics engineers all performing the same task on the same piece of equipment multiple times. Once the electrical design is completed, it is distributed amongst all other teams in the manufacturing cycle; mechanical engineering, manufacturing, procurement, and technical publications. Each team manually extracts the information that is required for their particular job function and then re-enters it into spreadsheets where it can be managed. This process is repeated by every team for every drawing.

Many of these processes are manual in nature and susceptible to human mistakes. Compounded by the fact that there are over one hundred thousand components and terminations, it is a certainty there will be many mistakes made throughout the course of a project. Mistakes on engineering drawings cause a domino effect throughout the organization. As you can see in figure 1 below a typical avionics project contains a myriad number of manual processes, each subject to human error.

One mistake in the design phase could easily equate to over one hundred hours of rework on the aircraft. If the mistake is not caught prior to release to production, then typically the entire assembly will need to be pulled from the aircraft.



Manual processes in a typical Avionics design project