UPDATE 1-GE starts flight trials for world's largest jet engine

SEATTLE, March 14 (Reuters) - General Electric hasbegun flight trials of the world's largest jet engine afterdelays caused by technical problems, the U.S. conglomerate saidon Wednesday.A special Boeing 747 test aircraft flew on Tuesday fromVictorville, California, with the new E9X engine mounted underits left wing, dwarfing the plane's three other engines.

The huge powerplant - as wide and tall as the fuselage of aBoeing 737 - is being built for the latest version of BoeingCo's long-haul 777, the 777X, which is due to enterservice in 2020.

During Tuesday's flight, engineers completed their test listand ensured key characteristics were working properly, GE saidin a statement confirming the flight, reported earlier byReuters.

The flight marks the beginning of a flight-test campaignscheduled to last several months, before the aircraft itselftakes to the skies in the first quarter of next year.

GE had been expected to start flight trials in December, butannounced in February it had found technical problems with boththe engine and the test plane during preparatory work.

The engine glitch will require the redesign of a part in thecompressor, which is near the front of the engine and does nothandle the hottest air flows.

Despite the delay, GE feels "very confident" it will meet a2019 target date for safety certification, a spokeswoman said.

GE's partners on the engine include France’s Safran, Japan’s IHI Corp and Germany’s MTU AeroEngines.(Reporting by Tim HepherEditing by Leslie Adler)