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Excerpts from article, from Jan 2016, are below.
Key points: (1) a pilot had to reprogram the flight in the FMS. (2) the lack of a debris field suggests a controlled ditching, so a pilot must have been in control at the end. (3) Khan had personal issues and is therefore the most likely suspect.
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The B777 is state of the art; probably the safest aircraft flying today. I know — I have many thousands of hours as captain on B777. How then could it disappear?
So, who changed the destination in MH370’s FMS?
Soon after the revelation that MH370 flew for more than seven hours to the southern Indian Ocean, I realised only an accomplished pilot could have managed this feat.
Simon Hardy, a former British Airways B777 captain, wrote a book that almost conclusively identifies Zaharie as responsible for the hijack of MH370 and its flight to the southern Indian Ocean, which likely ended as a controlled ditching as per Boeing flight manual procedures.
The aircraft suddenly turned westward over the South China Sea and flew a precise track — revealed by analysis of Malaysian military radar — across northern Malaysia. It avoided Thai military radar, then turned, after circling Zaharie’s home island of Penang, to the northwest up the Straits of Malacca and around the northern tip of Sumatra, avoiding Indonesian military radar, and eventually headed south. This shows precise control of the aircraft.
Why no debris? In 2004, a Flash Airlines B737 crashed after taking off at night from Sharm el-Sheikh because of pilot disorientation. It came in from 2500 feet at about 500km/h. Masses of debris floated for a long time. A much bigger B777 hitting the sea from 37,000ft at 1200km/h would produce a huge amount of debris that would float for months. Conclusion: it did not crash and was flying under control.
Analysis of Malaysian military radar revealed the aircraft had climbed to 45,000ft as it tracked across northern Malaysia. The only reason for doing this would be to incapacitate passengers and cabin crew by hypoxia. Only pilots’ masks have selectable pressure breathing capacity.
Hardy’s book is quite detailed about the rogue pilot theory and draws attention to the fact the aircraft circled Penang as if in a farewell to Zaharie’s home island. Former Malaysian opposition leader Anwar Ibrahim has confirmed Zaharie was a card-carrying member of his party (and an very distant relative) but has dismissed suggestions he may have diverted the plane as a political act. Hours before the flight vanished, Anwar, de facto leader of the People’s Justice Party, was sentenced to five years in jail after a court overturned his 2012 acquittal on a sodomy charge. Zaharie reportedly attended the hearing.
Several months after the MH370 disappearance I was told by a government source that the FBI had recovered from Zaharie’s home computer deleted information showing flight plan waypoints. Here, I assumed, was the smoking gun. To fly to the southern Indian Ocean, which has no airway leading from north of Sumatra to the south, the pilot would need to define flight plan waypoints via latitude and longitude for insertion in the FMC.
When nothing about this emerged from ATSB I rang my source. He confirmed what he had told me and left me with the impression that the FBI were of the opinion that Zaharie was responsible for the crash.
The flaperon found on a Reunion Island beach was definitely from MH370. The flaperon sits immediately behind the engines on a B777. The engines sit well below the fuselage and in a controlled ditching would contact the water first. The engines are held on by shear bolts and are expected to rip off (taking the flaperon with them) on contact with water.
When the flaperon was analysed by Boeing, the manufacturer said, along with US aviation safety consultant John Cox, that it had been broken off in a lowered position, consistent with the theory MH70 had made a controlled ditching into the sea.
The only logical conclusion I can draw is that Zaharie carefully planned and executed this very clever hijack scenario to end up in perhaps the world’s most unsurveyed deep-sea mountainous terrain, 6.5km deep in a cold, dark hell that would not be found — an area not that far north of Antarctica.
Byron Bailey, a veteran commercial pilot with more than 45 years’ experience and 26,000 flying hours, is a former RAAF fighter pilot and trainer and was a senior captain with Emirates for 15 years, during which he flew the same model Boeing 777 passenger jet as Malaysia Airlines MH370. 
Further, the manner in which this flight disappeared would require some advanced planning. Finally, the missing aircraft in question seems to be sufficient evidence to make a credible case for an intentional loss of life.
