Aircraft expert Ian Black previously worked as a fighter weapons instructor for the Malaysian Air Force, and is the author of two Haynes Manuals for aircraft, the McDonnell Douglas F-4 Phantom Manual and the RAF Tornado Manual. He flew the Tornado ADV in the first Gulf War and over Kosovo. He is now an A340 Airbus captain with Virgin Atlantic.

Could the aircraft have been ‘swapped’ mid-air?

Generally air traffic radars use something called a “Squawk” code - this is 4 digits, say '1234' - that is then used to transmit information to the ground radar of the aircraft’s position and other relevant detail. This is very easily disabled - it is operated with a simple on/off switch. The Boeing 777 has two separate systems for safety in the event of failure.

There is another angle which i think might be a possibility that the MH370 switched codes. If MH370 had a code of, say 4376, then it would be pretty easy to get another aircraft, say a Gulfstream 5 private jet, to fly up behind it and swap codes. The Gulfstream sets its squawk code to the same as MH370's code of 4376 then the B777 takes on the Gulfstream's code, and they then split... It would certainly make it easier for the B777 to continue on undetected.





Why did the Malaysian air force not scramble their fighters?

I actually trained the Malaysian air Force at Kuantan Air Base on the east coast of Malaysia and they have two MIG 29 fighter aircraft sat on alert 24/7 ready to scramble should an unknown aircraft enter their airspace – why were they not scrambled?

Most countries in this region spend billions of dollars on defence, in particular Air Defence – protecting their international airspace and waters.

The Indian Air Force have stated they only turn their radars on a 'need-to' basis – I think that's very unbelievable. I find it almost impossible that a Boeing 777 could be flying over land – whether that's Vietnam / Malaysia / India / or further north without anyone seeing it.

View photos Australia is leading the hunt for missing Malaysia Airlines flight MH370 along the southern search corridor. Photo: AP More

Could one pilot have ‘knocked out’ the entire passenger section?

Malaysia Airlines have stated that the Co-pilot and Captain did not ask to fly together and it was natural rostering that had them crewed on the same flight so we could probably say that the two were not working as a team.

On all airliners now there is what’s known as a “locked door” policy. That is to say the Flight crew are locked in behind a ballistic door and only allow authorized people in via a video entry system. However with only two pilots if one pilot leaves the flight deck to visit the bathroom he cannot get back in unless the other pilot opens the door. Although there is an emergency code it is possible to lock the other pilot out. In this scenario you would imagine the other pilot and the 250 would doo everything to gain entry and start using phones etc. – in the cabin there is a medical emergency system, which allows the crew to talk to various medical centers from the cabin.

My only thought on this was the person left in the cabin could have put on his oxygen mask- turned off the passenger Oxygen emergency supply and depressurized the aircraft – in a few minutes all the people in the cabin would be unconscious. The pilot could then repressurize the aircraft and remove his mask and fly normally with 250+ behind him incapacitated – not impossible.

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