 The air travel troubles born of Friday's global tech glitch continue. Nearly 900 flights in the U.S. canceled so far today. Delta Airlines continues scrapping flights even as it faces sharp criticism from the Transportation Secretary over its handling of a global software outage. Canceling hundreds of flights today on top of the roughly 1,300 for each of the three previous days, about a third of its scheduled flights. The Atlanta-based carrier, which was the worst affected...