A bomb disposal expert was wearing standard body armour as he tried to defuse a roadside device, an inquest has heard.
Capt Daniel Shepherd, 28, from Lincoln, was awarded the George Medal after he was killed in a bomb blast on 20 July 2009.
He was working in Afghanistan's Helmand province when he died.
The soldier was not wearing full body armour because it was too hot, the inquest in Lincoln was told.
Once he found the bomb he lay down on his stomach as he attempted to dismantle it by hand. It then it exploded, killing the soldier.
The inquest was told that the temperature on the day he died was between 45C and 50C and this would have made it impossible for Capt Shepherd to wear a full protective suit and operate freely.
The armour is thickly-padded and comes complete with head-casing and neck collar.
It weighs up to three stones (19kg) and makes bomb disposal experts sitting targets for Taliban snipers, a military source said outside the inquest.
When Capt Shepherd's widow Kerry received the posthumous George Medal on her husband's behalf in March, it emerged that prior to his death he defused 13 Taliban improvised explosive devices (IEDs) by hand in 36 hours.
While under sporadic enemy fire, he cleared the IEDs from a drugs bazaar without the use of a bomb disposal robot, protective suit or specialist electronic equipment.
Mrs Shepherd dedicated the award to his team, adding: "The medal was awarded in light of his ultimate sacrifice. He will always be loved and never ever forgotten."
Capt Shepherd served with the Joint Force Explosive Ordnance Disposal Group and had previously dealt with more than 50 devices while in Afghanistan.
He was awarded the Carmen's Sword of Honour, which is given to the most outstanding young officer of the year by the Royal Logistics Corps, in 2006.
The inquest continues.