The death of a Lee teaching assistant and army reservist on an SAS test march has been blamed on differences in preparatory training

The commanding officer of the signals regiment, using the codename SR44, told an inquest that the conduct of his training officers was not a factor in the fatalities on the Brecon Beacons.

Pointing out that all except one of his unit's candidates had completed the 16-mile march in July 2013, SR44 said he believed reservists' "pre-training" was the main cause of three deaths and several other heat casualties.

An inquest in Solihull has heard that more than a quarter of 37 reservists taking part in the 16-mile march fell victim to heat stress.

The reservists, who had done a different regime of "build-up" training, were joined on the march by 41 regular soldiers prepared for the test week exercise by the specialist signals unit.

Asked to give his view as to how reservists James Dunsby, Edward Maher and Craig Roberts came by their deaths, SR44 told the inquest: "I have reflected on it many times.

"In my view there were a number of contributory factors.

"I do not believe that the conduct of the march was one of these factors, nor the conduct of (signals regiment training officers) 1A and 1B.

"Of those students who had conducted pre-training in my unit, all bar one completed on that day, and the one that didn't was not heat-related.

"The difference in preparatory training is what I identified as the primary factor.

"I do believe that checkpoints were correctly manned with the correct people, who would have assessed candidates correctly."

SR44 had been in charge of the signals regiment, which supports special forces units on overseas operations, for around two years when the "selection" march took place on July 13.

The officer said he had assumed the reserve unit which prepared 37 of the candidates "understood their responsibilities" and would have ensured their students were ready to commence the march in line with its required standards.

Giving his evidence from a screened-off witness box, SR44 told the inquest: "I saw it as their responsibility and as their business effectively to get their candidates to the appropriate start line.

"My understanding at that time was that I had the right experienced people, particularly in 1B, and supportive directing staff to run that 'selection' with risks as low as was reasonably practicable."

Although he admitted that he had not seen the risk assessment for the march, SR44 added: "I still believe that I had the best personnel to run that pre-training and then commence 'selection'.

"We were being asked to facilitate an exam according to direction and standards as laid down by superior headquarters.

"The personnel I had there had not only seen previous courses but also deployed on operations and performed to an extremely high standard."

Birmingham and Solihull coroner Louise Hunt questioned SR44 about his role in asking reservists to continue with test week, a day after the deaths.

Pressing on with a second march, albeit at a reduced length and with more directing staff, on July 14, had been a "very difficult" decision, SR44 said.

"This selection is part of a process to produce trained soldiers who are to deploy on specialist operations," he told Ms Hunt.

Another officer, who was in charge of training the reservists who died, also gave evidence to the 18th day of the inquest.

Known by the cipher 2A, the former reserve squadron sergeant major, was also asked for his views on the decision to allow reservists to undertake a march on July 14.

"I had mixed feelings," 2A told the hearing. "I was concerned for the remaining students, both in terms of the march the next day but also in terms of if they didn't do the march, they would be sat staring at empty beds.

"I was really undecided on which decision to take I'm afraid."

Explaining his view of what had caused the events of July 13, 2A pinpointed the length of the march, the heat, the unusual windless conditions, and clothing as factors.

Meanwhile, the inquest heard a series of 999 calls made by march-directing staff to request assistance from the ambulance service.

In one call, made at 4.40pm on July 13, a soldier helping to run the march said a colleague was trying to administer CPR to a casualty.

After being asked the tell the operator what had happened, the unnamed soldier said of the casualty: "He was doing a march, he'll be suffering from heatstroke."

The soldier was then informed that he needed to answer a series of standard questions and told the operator: "Right, but this guy is going to die, I need someone."