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The U.S. Air Force, which grounded its fleet of T-6A trainer aircraft almost four weeks ago due to a rise in physiological episodes (PEs), announced Feb. 27 that the planes are now cleared to return to flight.The Air Force said it has determined that the PE surge was caused by the unexpected degradation or failure of a “handful of components” in the plane's pilot breathing system, also known as the on-board oxygen generation system (OBOGS). Those components will now be…
