Rolls-Royce ran the Trent XWB engine for the first time on Thursday aboard a testbed in Derby, UK, the company announced on Friday. Chosen to power the Airbus A350 XWB, the Trent XWB remains the sole powerplant option for the new airliner. The engine’s first run meets program commitments established in 2006, said Rolls-Royce.

The engine company has collected orders for more than 1,000 of the engines, making it the fastest-selling Trent engine ever. Rolls-Royce claims the engine–the sixth of the Trent family–offers 28 percent better fuel efficiency than pre-Trent generation engines. The first Trent engine, the Trent 700, began service in 1995 and the family has now accumulated more than 40 million hours in service.

“This is a great day for the A350 XWB program, for Rolls-Royce and Airbus,” said Didier Evrard, head of the A350 XWB program. “The first engine run of the Trent XWB has been achieved fully on time with our schedule and is a major milestone that marks the coming to life of the new aircraft.”

The first run starts the most extensive pre-flight program in Trent history, before the start of flight tests on an Airbus A380 testbed next year and A350 XWB flight tests in 2012. The company expects to have seven development engines running by early 2011.