Military chiefs should "should hang their heads in shame" over the death of a British paratrooper in a landmine explosion, a coroner said today.

Corporal Mark Wright in a picture released by the army

Andrew Walker ruled the blast that killed Corporal Mark Wright, 27, was caused by the "downwash" from a Chinook helicopter sent to rescue a platoon stranded in an unmarked Afghanistan minefield.

Walker gave a narrative verdict at the conclusion of a two-week inquest at Oxford coroner's court. He said Wright's death could have been avoided but for a lack of equipment, which he said "was simply about money". He said it was "lamentable" that the UK was not equipped to stage an effective rescue.

Wright, from Edinburgh, died from a landmine blast as he went to help an injured colleague at Kajaki, in Helmand province, on September 6 2006.

He was posthumously awarded a George Cross for bravery. Six other soldiers were injured; three of them lost limbs.

Walker said serious failures contributed to Wright's death, including the lack of UK helicopters in Afghanistan fitted with a winch, the downwash from the Chinook sent to the minefield, and the delay in sending a suitable helicopter.

There was a lack of batteries for radios at observation posts, which reduced the soldiers' ability to communicate, and soldiers had no information about the minefield.

He said soldiers' training to locate and mark mines failed to use the latest technology.

Walker described Wright as "an exceptional soldier" who acted with "unhesitating courage". "This selfless courage forms part of a tradition within our armed forces and Cpl Wright will continue to be an inspiration for those who follow.

"That a brave soldier is lost in battle is always a matter of deep sadness but when that life is lost where it need not have been because of a lack of equipment and assets, those responsible should hang their heads in shame."

The soldiers, from 3rd Battalion the Parachute Regiment, became trapped in a minefield after a sniper, Lance Corporal Stuart Hale, strayed into the unmarked area. Hale lost a finger and part of a leg when a mine exploded.

Wright and his colleagues went to help Hale and radioed base for help. Lieutenant Colonel Stuart Tootal, the battalion's commander who was at the base, told the inquest his demand for a US Black Hawk rescue helicopter was initially rejected by the Nato command in the country and he felt he had no choice but to send a Chinook without a winch.

When the Chinook approached, the troops feared it would land on a mine and screamed for it to go away – but their pleas went unheeded and the helicopter's downdraft caused a mine to explode, wounding Wright and the man next to him.

In spite of injuries to his chest, face, arms and neck, Wright continued to give first aid to his colleagues and tried to maintain morale and keep calm.

Three hours later the men were picked up by two Black Hawk helicopters but Wright died of his injuries before reaching the field hospital.

The Ministry of Defence is understood to be negotiating compensation with Wright's family and the soldiers who were injured.

After the inquest verdict was announced, Wright's father, Bob, and mother, Jem, said they were proud of the courage shown by their son and his colleagues.

Bob Wright said it had been painful to listen to the "catalogue of errors" that led to his son's death. "The coroner has made recommendations that must be followed. Jem and I don't want any other families to experience the loss of their child in similar circumstances."

The family's solicitor, Paul Harrington, said the Wrights wanted lessons to be learned from the "systemic failures" that led to their son's death. The Ministry of Defence should urgently plan better rescue procedures, he said.

The commander of joint helicopter command, Rear Admiral Tony Johnstone-Burt, said he was confident that current resources were able to meet the required tasks.

Johnstone-Burt, who is responsible for the provision of all battlefield helicopters and crews to Afghanistan and Iraq, said all UK helicopters in Afghanistan were now fitted with winches. Helicopter winches were not used to extract people from minefields, however, "because of the lethal risks involved".

He said: "In the spirit of our shared efforts in Afghanistan, resources are pooled across the countries fighting there. In addition to UK Chinook, Apache, Sea King and Lynx helicopters, our forces can also access significant numbers of other types of helicopters provided by our allies."