Rolls-Royce has revealed it completed the first ground tests of the Trent 1000 package C version, which is to be employed on the Boeing 787-9 next year.
The ground runs began in Derby last month and will continue over the next eight weeks, before a three-month flight test programme begins on the UK manufacturer's Boeing 747-200 testbed in the summer.
Two engines are currently in production for the flight tests.
The upgraded powerplant will provide 74,000lb of thrust and should deliver a 1% fuel burn improvement over the package B engine standard, according to Rolls-Royce.
It features a new turbine case cooling system, which should improve efficiency.
The package C variant will not only be used for the larger 787-9, which is scheduled to enter service with Air New Zealand in 2014, but will also become available for the baseline 787-8 model later that year.
Flight tests for the 787-9 are due to begin in 2013.