How do you dramatically reduce the time needed for wiring testing on an aircraft bristling with more than 700 connectors?
That was the problem facing Giorgio Cagnin and his team at Alenia Aermacchi as production of the company’s new M-346 advanced jet trainer began. The aging test system they had in place was already causing delays.
Alenia Aermacchi is the only aircraft manufacturer that offers products covering every phase of military pilot training, from ground-based training systems to advanced jet trainer aircraft. Their Training Systems division produces the M-346 – and their new M-345 HET primary jet trainer – at the company’s plant in Venegono Superiore, Italy.
Sales of the M-346 have been brisk. With orders in from four countries and deliveries scheduled to ramp up sharply from one aircraft per month to four, it was clear their existing system would soon become a bottleneck that could put millions of Euros worth of milestone payments at risk.
A Problem of Complexity
That system – a DIT-MCO Model 2503 – had been used successfully to test the prototypes of the M-346. But with the new plane’s large number of test points, the hook-up and testing process was proving extremely labor-intensive.
Housed in four large cabinets, the Model 2503 was very difficult to move. This necessitated the use of long, heavy adapter cables to reach the aircraft. Each cable was in three sections which had to be unrolled and connected each time a new aircraft was rolled in for testing.
On earlier, less complex aircraft, and on the prototypes (when there was more time), this had never been a problem. Now it was. Cagnin says it would take six to seven technicians – working two shifts – two to three days just to connect each new M-346.
To make matters worse, the adapter cables – in use for ten years on the prototypes – had become unreliable. Broken wires, resulting in failed tests, were common. Time was lost waiting for repairs. Plus, the adapters were the same color as the aircraft wiring harnesses, which often caused confusion during hookup and troubleshooting.
Operators were constantly in doubt. Were faults found actually in the aircraft wiring? In the adapter cables? Or caused by an incorrect adapter connection? Testing was slowed by excessive troubleshooting. It was taking three to four weeks to test each production M-346.
“Operators couldn’t adequately concentrate on the aircraft,” says Cagnin. “Real wiring faults might be obscured by test system failures. It was a dangerous situation.”
Finding a solution became Cagnin’s top priority.
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