Design quality requires use case analysis.   Every once in a while, I see an example outside of my own application area.  Here’s the details...

 

In 2007, Ireland bought two Israeli Orbiter UAV systems, for $550,000 each. They had lost two of their six UAVs in Chad, where a battalion of Irish peacekeepers are operating. The second one UAV casualty apparently tried to fly back to Ireland, after it lost its communications link with the operator. The Orbiter is programmed to head back to the operator if it loses its comm link. But this Orbiter apparently still had a GPS location back in Ireland in its memory, and headed there. Since Ireland is 5,000 kilometers from Chad, the Orbiter ran out of juice and landed about 4,800 kilometers short of its goal.

 

The designers were trying to provide some appropriate default behavior in case the UAV lost contact with its operator. This is good, and may not have been a big deal in Israel, because most of its UAVs are operated near its borders.  No one thought about the possibility of using the UAV far outside a country's borders.  It should have recorded the original operator's location in order to fly back to that location.

 

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