THE death of a 14-year-old boy at a Hampshire RAF cadet training camp could not have been avoided despite failings in the way the exercise was run, a coroner has ruled.

David Efemena died in March last year on an understaffed training exercise that should have been cancelled, at the Bramley defence training estate in Hampshire, after falling seriously ill in his tent at night.

It took adult supervisors around 30 minutes to reach him from their base 1.9km away, Walthamstow Coroner's Court heard.

After convincing his parents to allow him to join the Air Cadets, David set off for the weekend trip on March 21, but became ill the following day after a day of strenuous exercises, and later died.

Delivering a narrative conclusion, assistant deputy coroner Nadia Persaud said she did not consider that the failings of the way the camp was run contributed to the ''hard-working, diligent'' teenager's death, but made several recommendations to the RAF.

She said: ''There was no evidence during the course of the inquest that there was a real prospect that David's death could have been avoided.''

She recommended the RAF should consider having defibrillators on cadet training exercises, and said the ''new policy on communications remains unclear'' and checks should be carried out prior to sleeping.

The inquest was told that another cadet was awoken around 10 times on the night of March 22 by ''strange gargling or coughing'' noises coming from David, who was also shaking violently.

When older cadets became aware of a problem early on the Sunday morning, they tried desperately to contact the adult supervisors by walkie talkie.

When asked how long it was until help arrived, senior cadet Craig Barnett said: ''I got on my radio and started moving about to see if I could get a bit of signal but I thought that because it was still quite early the staff may still be asleep, so that is why I couldn't get in touch with them straight away, and because the area we were in had quite a lot of trees that could interfere with the signal. So I would say it could be around half an hour before I finally reached the staff.''

RAF Squadron Leader Neil Knowles, who was delegated to sign off on the training exercise, told the inquest he would have expected it to have been cancelled because there was a lack of adult supervision, or for more staff to have been drafted in.

Squadron Leader Christopher White, who planned the training event with his brother Michael, admitted there had not been adequate adult supervision at the camp.

Ms Persaud asked: ''Between 10pm on Saturday 22 March and 7am on Sunday 23 March, do you consider there was tight and effective supervision of the cadets?''

Mr White initially replied that there was adequate supervision because two senior cadets, aged 17 and 18, were ''in charge''.

He was then asked: ''In terms of the adult staff members present, was there tight and effective supervision of the cadets?''

There were several moments of silence before Mr White quietly answered: ''No, probably not.''

The normal ratio of adults to cadets should have been one to four but there were 13 children and only three staff, the inquest was told.

When asked if the radios had been tested over the distance, Mr White answered: ''Not personally, no.''

He added, that ''in hindsight'', the cadets should have had a mobile phone with them in case of an emergency.

Michael White said he heard crackles over the radio as he was on his way to the cadets' camp on the Sunday morning.

He added: ''As I was crossing the bridge I got a jumbled message, I couldn't make it out. I couldn't make out the first part, I couldn't make out the message, but from what I could hear there didn't seem to be any urgency in the voice.''

He continued: ''When I got the full message I got there as quick as I can. The message I got was that David was shivering but again it didn't seem urgent. I thought, maybe hypothermia, worst case, so I ran up.''

Mr White said it took him around 15 minutes to reach the cadets after receiving the full message.

He arrived just after 7am and the ambulance was called at 7.11am.

When paramedics arrived eight minutes later David was in cardiac arrest and his temperature had dropped to 30.7C, the inquest was told.

The teenager was taken by air ambulance to hospital but was dead when he arrived.

Ms Persaud recorded that David died of an anomalous origin of the right coronary artery and seizure.

David's father, Felix Dibie, said his son was ''a fit and active'' teenager who never complained of any heart pain.

David joined the Air Cadets to follow his dream of becoming an aeronautical engineer.

Mr Dibie said: ''He was a lovely boy. All around he was a son that you were proud of.''