THREE army reservists who died  in an SAS training exercise were carrying backpacks weighing at least 49lb across the Brecon Beacons in heat expected to top 27C (80.6F).

The three were among 78 soldiers – all carrying backpacks of the same weight and not including their food and water – that had set out on the Pen Y Fan march on July 13, 2013 – one of the hottest days of that year.

An inquest opening today (Mon) in Solihull heard that the 78 - 37 of them reservists - marched in temperatures topping 27C (80.6F) along five different routes covering 26.4km (16.4 miles) with five checkpoints.

Each candidate was expected to carry a rucksack weighing no less than 49lb, not including food and water, and had GPS trackers.

On the march, the inquest heard, concerns were raised over a number of soldiers collapsing and needing medical attention.

Lance Corporal Edward Maher, Lance Corporal Craig Roberts, and Corporal James Dunsby subsequently died.

Roberts, 24,  was pronounced dead on the mountainside, while Maher and Dunsby, both 31, were taken to hospital.

Maher died three hours later in Merthyr Tydfil’s Prince Charles hospital, while Dunsby was transferred to the Queen Elizabeth hospital in Birmingham, where he died on July 30 2013.

The inquest, listed for four weeks, will explore how the exercise was conducted, briefings given to directing staff, risk assessments  and whether there was timely intervention in the dead soldiers’ welfare.

Evidence will also outline what checks were made on forecasts that pitched the hottest day of the year and whether or not the assessment route should have been reconsidered or even aborted.

Other issued to be addressed are:

- Procedures in place in case of an emergency, what water was available and whether it was sufficient.

- Identifying whether a GPS system for tracking soldiers was working and being properly monitored

- Timeliness and adequacy of emergency response.

The inquest continues.

BACKGROUND – THE BRECON BEACONS SAS TRAINING DEATHS

Supervisors of the training exercise won’t face manslaughter charges.

In March, the CPS confirmed that an independent  review of an initial decision not to charge over the deaths had reached the same conclusion.

In a statement, the CPS said that conclusion concurred with the assessment of “ insufficient evidence to provide a realistic prospect of conviction” on charges of gross negligence manslaughter.

An investigation into the deaths by the health and safety executive (HSE) is on-going supported by Dyfed-Powys Police which carried out the criminal inquiry.

This review into the ruling out of criminal charges started in September last year after an appeal by two of the soldiers’ families.

The deaths saw the HSE say SAS training posed a “serious risk” to soldiers with the regiment put under orders to tackle risks revealed by an ongoing investigation.

Subsequently, the HSE s served a Crown Improvement Notice ordering the Ministry of Defence (MoD) to improve its response to heat illness risk on exercises.

That order meant an HSE inspector believed such exercises presented a serious health and safety risk.

The notice stated that the MoD as an employer “failed to make a suitable and sufficient assessment” of risks to the health and safety of the soldiers on the test, including those relating to heat illness.

With no right of appeal, the MoD had to comply over issues including the duration and intensity of the exercise, the suitability of clothing, and availability of water.

The HSE has acknowledged that the MoD "complied with the notice and took action”  ahead of the next selection test exercise in January 2014.