By Andrew Tangel Boeing Co. is nearing a fix for engine covers like the one that broke apart on a United Airlines 777 jet over Colorado earlier this year, people briefed on the matter said. The fix, expected to be completed as soon as early June, would strengthen the engine covers to prevent plane parts from detaching midair and striking the aircraft or falling to the ground below, these people said. After a United 777's engine failed shortly after takeoff from Denver in February, its external cover broke apart, raining metal on a nearby suburb. No one was injured, and the flight landed safely.