“Two Alaska Airlines flight attendants who were injured when a 2007 flight from Seattle to California encountered turbulent air have filed a legal claim against a national weather forecasting service and against the U.S. government.  Donna Dacko and Inga Isakson were working on the flight to Ontario, Calif., on Dec. 25, 2007, when the aircraft hit “previously unreported severe turbulence” before landing, according to the claim filed Thursday in U.S. District Court in Seattle.  Isakson slammed her head against a metal chair arm and on a metal frame beneath a passenger seat, according to the claim. A pool of blood surrounded her head and she was seen “frothing at the mouth;” she lost consciousness, the claim said.”