The recent mid-air collision in Brazil of a new regional airliner (fitted out for use as a business jet) and a Boeing 737 has people baffled.  How could two brand-new airplanes with advanced avionics, flown by two professional pilots in each plane, collide at 37,000′?  The precision of modern avionics may well have contributed to this collision.

Source: Philip Greenspun’s Weblog