Air Crash Investigations - The Disappearance of MH370 - Did Captain Zaharie Ahmad Shah Prevent a Disaster?

On 07 March 2014 at 1642 UTC, a Malaysia Airlines Flight MH370, bound for Beijing departed from Kuala Lumpur International Airport with 239 persons on board. It was a Boeing 777-200ER. A half hour in the flight all communication stopped suddenly and the plane changed course to the remote South Indian Ocean. Nothing was heard or seen of the plane until on 1 August 2015 a piece of the wing was found on the Beach of Reunion Island in the Southwest Indian Ocean. The accident is very similar to the crash of Helios Flight 5223 on 13 August 2005. This plane suffered from a sudden leak in the cabin pressure, crew and passengers suffered from hypoxia, three hours later the plane hit a mountain near Athens, Greece. Did Captain Shah of MH370 try to avoid crashing on Beijing? What is the role of the huge American base of Diego Garcia in the Indian Ocean in the story?