Raisbeck Engineering has started FAA certification flight-testing of its new Hartzell composite five-blade swept propeller mod for the Beechcraft King Air 350 series. The Raisbeck/Hartzell team completed all ground and flight vibration and governor output pressure testing early last week before clearing the aircraft for flight-testing, which is expected to be completed by month-end. The new King Air 350 propellers will be formally introduced at the NBAA Convention next month in Orlando, Fla., where more details and preliminary performance improvements will be released. Production deliveries are scheduled to start in July next year.