When a Malfunction on Land Keeps a Fleet of Delta Planes From the Sky - The New York Times

Oops; also see Delta computers crash, causing delays and cancellations. Experts say it shouldn’t have happened (The Washington Post)

"“In the case of Delta, whatever occurred was clearly a catastrophic failure, and it is alarming that the backup system didn’t kick in,” said Henry Harteveldt, a travel industry analyst at Atmosphere Research Group.

Delta said the problem was touched off by a power failure about 2:30 a.m. Eastern, shutting down computers and grounding flights for about six hours before the airline began to bring its systems back online. (As it happens, the culprit inside Delta — a failed switchgear, an item similar to a circuit-breaker box in a house — is a piece of equipment typically installed to guard against breakdowns.)"

When a Malfunction on Land Keeps a Fleet of Delta Planes From the Sky - The New York Times