The mother of a teenage air cadet killed on a training flight said he was "utterly failed" by the RAF, after an inquest jury found the pilot's severe spinal condition contributed to the tragedy.
Nicholas Rice, 15, and Flight Lieutenant Mike Blee, 62, died after the RAF training plane they were in collided in mid-air with a glider over Abingdon, Oxfordshire, on 14 June, 2009.
Following a week-long inquest at Oxford Crown Court, jurors returned verdicts of accidental death. The panel of four men and six women said there were a number of contributory factors, including Flt Lt Blee's medical condition - ankylosing spondylitis - which meant his ability to look out was compromised and left his back vulnerable to breaking.
After just over 11 hours of deliberation, the jury found, by a majority of nine to one, that the pilot was dead before the plane hit the ground.
The inquest heard evidence that Flt Lt Blee might have been killed on impact with the glider, such was the severity of his back problem.
Investigations after the accident showed that the pilot's harness was still on when the plane crashed to the ground, but Nicholas's was not, indicating that the teenager might have been trying to escape from the craft in the last moments of his life. He died from multiple injuries sustained on impact.
His mother Julia Rice said: "This inquest has been the culmination of the worst period of my life.
"In allowing my child to participate in air experience, I trusted that the RAF knew what they were doing and that they would take care of him. It was devastating to discover that they had utterly failed him.
"For me, this horrendous experience has come from the pilot's disability, ankylosing spondylitis, which meant that the initial impact of the mid-air collision resulted in the pilot's incapacitation and left my son struggling in vain to escape the plane that, in fact, was capable of being flown back to the air base."
The jury foreman told the coroner that both deaths were contributed to by the pilot's medical condition and subsequent incapacitation after the crash, adding that a lack of abandonment training contributed to Nicholas's death
Mrs Rice said: "Unfortunately, the abandonment training by the RAF was woefully inadequate for these cadets."
The court heard that the two-seater Tutor plane spiralled and then nosedived after the crash at 4,150ft, taking 24 seconds to plummet to the ground.
Pathologist Kenneth Shorrock, who carried out post-mortem examinations on both victims, told the inquest that Flt Lt Blee's condition - an inflammatory spinal disorder which causes fusion of the bones in the spine and the neck - can reduce the ability to turn or raise the head and make the spine more prone to breaking.
Asked by Alison Thompson, deputy Oxfordshire coroner, whether it would have compromised his ability to look out from the aircraft, he said: "On the basis of my objective findings - what I saw - most certainly, and from what I have seen from his medical records, that would tend to confirm that."
Andrei Calin, a consultant rheumatologist, told the inquest jury he believed the impact with the glider would have had sufficient effect to cause Flt Lt Blee's spine to fracture.
The doctor, who never examined the pilot, said that based on information he had seen, he considered the spinal condition to be "at the far end of the spectrum" of seriousness.
He said: "A minimal jarring event would put the spine at risk of fracture, just snapping."
The jury noted that the high number of gliders in the area on the day of the collision, and the difficulty in seeing them, were also factors in the deaths.
In a statement read by their solicitor after the verdicts, Flt Lt Blee's family said: "Mike was a loving husband, father, son and brother and continues to be sorely missed.
"He lived a full and active life and positively contributed to the lives of many. He was highly respected by his colleagues and fondly remembered by all who knew him. Our condolences remain with the Langley Rice family, whose loss was so tragically entwined with our own."
Group Captain David Lee, speaking outside the court on behalf of the RAF, said: "Our thoughts are with Mr and Mrs Rice, Mrs Blee and their families, and we will continue to do our utmost to provide whatever support they need.
"I'm sure that the inquest will have been a difficult time for them but I hope it has also helped them as they continue to come to terms with their loss.
"No parent expects to lose their child at such a young age and in such tragic circumstances and we can only imagine what Mr and Mrs Rice must have gone through in trying to come to terms with their loss."