The error in American Airlines' software that delayed flights last night originated from a duplicate map of Ronald Reagan Washington National Airport, and it won't be fixed until an update is pushed out May 8th, says Michael Pound, a spokesman for Jeppesen, the Boeing subsidiary that makes American's app. Until then, pilots will rely on either print-outs or PDFs of the airport accessed through a separate app, Pound says.

American Airlines became the first airline to get FAA approval — in 2012 — for iPad use in all stages of flight. Though many airlines use iPads as electronic flight bags, the version of software American uses is unique, so it's the only airline affected by the glitch.

"We began to get calls from American saying they were having problems with the app pilots use for navigational charts," Pound says. "We found one single chart in the database causing the app to become unresponsive." The problem is that the chart has the same name as another chart for Ronald Reagan Washington National Airport — and the app can't handle the duplicate.

Not every pilot who was affected was flying to DC — last night, Bill Jacaruso's flight was headed from Dallas/Fort Worth to Austin when both the pilot's and co-pilot's iPads went blank. The outages there could have happened for a number of reasons, Pound says — either because the affected chart was open in the background or because it was stored in the pilots' favorites.

Updated 3PM ET: Jeppesen originally told us that pilots would have to revert to paper; they contacted us after publication to tell us pilots would be able to choose between print-outs of PDFs, or PDFs accessed through a different program on the iPad.