Normally Risedale Beck in the Catterick Garrison training area is only inches deep, but some witnesses have said it was up to waist height when Private Andrew Borkertas died on June 15 last year, after two months worth of rain fell in two days.

The platoon was near the end of a 24-week course at the Infantry Training Centre and was on an eight-mile combat fitness test being led by Corporal, now Acting Sergeant, Jason Dudley.

He told the Harrogate inquest that the water was midway up his thighs when he crossed the ford, but did not consider it was dangerous.

He reached the other side, two- and-a-half metres away, when he heard laughter and turned round to see that a recruit had fallen in the water and was making his way out. As a precaution, orders were given for the recruits to link arms and Sgt Dudley went back into the water to join up with Sgt Gareth McConville.

It was at this point, he told the inquest, that they were hit by the surge of water. He said: "I have never felt anything like it. It was definitely deeper – a big push of water. It was the scariest thing I have seen in my life. It hit us like a bowling ball and skittled us. We were knocked for six."

Seven people who were in the water at the time, including Sgt Dudley and Sgt McConville, lost their footing along with several recruits. Two Corporals, Robert McGowan and Scott Seaton-Norton, ran downstream to help those who had been swept away.

Cpl McGowan went into the water and managed to reach Pte Borkertas, who was panicking and shouting for help. He held on to him and managed to calm him down, but as they tried to grab overhanging branches to pull themselves to safety, Cpl McGowan lost his hold and Pte Borkertas disappeared.

Sgt Dudley described spending 40 minutes trying to find Pte Borkertas. He said: "We were feeling for Andrew with our feet, but we could not keep our feet on the floor to find him."

Asked by the Coroner, Geoff Fell, if he had seen Pte Borkertas in the water, he said "No."

Cross-examined by Timothy Brennand, who represents Pte Borkertas's family from Grantham in Lincolnshire, Sgt Dudley said he had not been aware that two platoons which crossed the beck earlier had taken precautions by linking arms and their Army ambulances had made diversions to avoid the water.

Asked whether he now thought he should have stopped the platoon , Sgt Dudley said: "I would not have done anything differently to what I did that day."

But in reply to Ministry of Defence barrister Simon Hilton, he said it was standard operating procedure for those in charge of a platoon to ring back and issue a warning if they encountered a problem. "If I had formed a chain to get through, I would have rung back," he added.

The inquest continues.