Pilot Andy Hill's claim that he 'blacked out' before crashing his plane in 2015 is not backed up by video evidence, according to an RAF doctor.
Hill told paramedic Mark Durham that he felt a pain in his chest and 'blacked out' whilst flying the Hawker Hunter, his trial heard this morning.
However RAF doctor Wing Commander Nicholas Green said video taken from the cockpit of the Hawker Hunter 'does not show' Hill losing consciousness.
Andy Hill, 54, of Standon Road, Buntingford, who was flying the Hunter when it crashed is charged with 11 counts of manslaughter by gross negligence. He denies the offices.
Much of the questions this morning centered around footage from inside the cockpit of the Hunter, which appears to show Hill looking around and out the window.
READ MORE: Pilot Andy Hill had 'no recollection' of events leading up to tragic plane crash
'You stop looking around'
Wing Cdr Green was asked if Hill could have experienced A-LOC (altered level of consciousness) or other cognitive impairment during the flight.
A-LOC causes pilots to lose their ability to see, the trial heard.
Prosecutor Tom Kark QC said: "As far as A-LOC is concerned, if you could not see their face would it appear as if they have A-LOC?"
Wing Cdr Green replied: "In our experience because of the loss of vision you stop looking around.
"People stare ahead of them and they stop turning to the side."
He continued that there is 'no measurable' cognitive impairment before A-LOC happens in the G-force levels being discussed.
Wing Cdr Green said he found 'no indication' that Hill experienced either A-LOC or G-LOC (G-force induced loss of consciousness).
Defence: lack of experiments means we cannot be sure
But defence barrister Karim Khalil QC asked: "Prior to a complete loss of sight do you accept that there has been a gradual or decreasing ability to see?"
Wing Cdr Green agreed that this was possible, depending on the G-forces.
When asked about other forms of impairment besides the ability to see during this phase, Wing Cdr Green replied that there were none to his knowledge.
However Mr Khalil argued that the absence of experiments on the subject mean 'one is not able to conclude' that there is no cognitive impairment below A-LOC.
Trial now in its seventh week
The trial is now in its seventh week, with early indications that evidence will conclude in the next few days.
Throughout the trial so far the prosecution have alleged that Hill was negligent and the disaster was caused by pilot error.
However defence barrister Mr Khalil argued that Hill suffered a cognitive impairment at some point during the flight and not in control of what he was doing.
The trial continues.