Interflug
I'm not aware of a confirmed Vietnamese source seeing a turnaround on primary radar.
Neither did the Malaysians ever claim to have tracked a turnaround....
So let's say the turnaround is an ASSUMPTION.......
Why are you still flogging this a year and a half later?
Vietnam - This story was carried March 8th by the Malaysian Insider:
"We informed Malaysia on the day we lost contact with the flight that we noticed the flight turned back west but Malaysia did not respond," Vietnam deputy minister of transport Pham Quy Tieu was quoted as saying by AFP today. "
Malaysia Airlines search mired in confusion over plane's final path | World news | The Guardian
Military radar trace shows MH370 turn-back, but no distress signal - The Malaysian Insider
March 11th
Singapore also monitored that portion of the flight and saw the turnback:
"A Singaporean air traffic surveillance and control unit also picked up the signal that MH370 "made a turn back before it was reported to have climbed 1,000 metres from its original altitude at 10,000 metres" Malaysian military now reveals it tracked MH370 to the Malacca strait - The Malaysian Insider
12 March "Air Vice Marshal Montol Suchookorn of the Royal Thai Air Force said an unidentified aircraft was detected at 1.28am, eight minutes after MH370'S transponder stopped communicating. He said the plane was following a twisting path, turning towards Butterworth....."
Thursday 1 MAY 2014
Press statement by Hishammuddin Hussein Minister of Defence and acting Minister of Transport:
"2. The military’s tracking of MH370
As stated previously, Malaysian military radar did track an aircraft making a turn-back, in a westerly direction, across peninsular Malaysia on the morning of 8 March.
The aircraft was categorised as friendly by the radar operator and therefore no further action was taken at the time.
The radar data was reviewed in a playback at approximately 08:30 on 8 March. This information was sent to the Air Force operations room at approximately 09:00.
Following further discussion up the chain of command, the military informed the Acting Transport and Defence Minister Hishammuddin Hussein at approximately 10:30 of the possible turn-back of the aircraft.
The Minister then informed the Prime Minister, who immediately ordered that search and rescue operations be initiated in the Straits of Malacca, along with the South China Sea operations which started earlier in the day."
Then there is the Inmarsat data and now the flaperon; denying the turnback is on about the same level as denying an aircraft hit the Pentagon or denying that Lee Harvey Oswald was in the book depository.