Case Study: Data Loader for Avionics

Customer Need: Upgrade to new technology

Background:

Airborne Data Loaders greatly simplify the distribution, onboard storage and management of loadable software applications and databases across an airline’s operation, by facilitating data transfer between ground-based computers and onboard avionics equipment. This application was for a Boeing 737 and Airbus A320 aircraft, and resides both in the airplane and on the tarmac for diagnostic testing. This was an existing customer for IEE.

The customer desired to upgrade their IEE DayStar® Nova LCD character display with a new AMLCD display. Requirements included support for full color display, USB, and sunlight readability; crucial in a cockpit environment.

They also required flammability testing on the components.

Avionics Data Loader
Avionics Data Loader
 

Challenges:

A key challenge was designing and fabricating the interface card and back panel in a way that would allow this to be a drop in replacement for the existing panel. Integrating the custom metal front panel assembly with tight sub millimeter tolerances was also required, along with versions with and without floppy disk insertion. The customer also needed a short and a tall version of the assembly.

An additional challenge was fabricating a solution, which minimized the re-certification efforts.

Solutions:

IEE engineers worked side-by-side in true collaboration with the customer's engineers in the IEE prototyping lab for many weeks. IEE designed the front-end assembly while the customer's engineers designed the back end.

Selecting the right panel is the most important decision made, as it means tradeoffs among resolution, temp, availability, viewing angle, orientation, refresh time and contrast ratio. In this case, the electrical and mechanical interfaces were critical to the application, and were taken into account in the display selection.

IEE selected 3.8 inch QVGA LCD display with an unusual configuration of CCFL edge lighting on three sides and replaced this with 3 segments of LED strips. Then they added USB ports, 4 tactile switches, enunciators, and a solid-state disc slot.

For the mechanical interface, IEE designed a custom friction hinge with EMI sealing to drastically reduce emissions when the panel was closed.

IEE successfully conducted flammability testing on the components and delivered these new upgraded units, which they are still manufacturing for the customer today.