Two workmen who should have been in the crane that was hit by a helicopter escaped death by minutes because they overslept.
Richard Moule and Nicki Biagioni were late for work and hurrying to climb the crane in Vauxhall when the helicopter clipped the structure and plunged 700ft to the ground, killing Berkshire pilot Peter Barnes.
A second man who died in the accident has been named as Matthew Wood, 39, from Sutton, south London, who is believed to have been walking to work when he was killed.
Twelve other people were injured and police said it was a "miracle" more were not hurt.
Stunt pilot Mr Barnes, 50, who has piloted helicopters for movies such as Die Another Day, was alone in the aircraft amid thick cloud when it clipped the crane.
The helicopter was undertaking a commercial flight from Redhill, Surrey, to Elstree, Hertfordshire, but Mr Barnes asked to be diverted to Battersea heliport because of bad weather.
Tributes have been paid to a Berkshire pilot who died when a helicopter crashed into a crane in London.
Kevin Hodgson, who worked alongside Peter Barnes on life-saving missions with the Great North Air Ambulance, said: "Pete was as good a guy as you can imagine and one of the best pilots I've ever had the pleasure of flying with."
An investigation is now under way into how Capt Barnes hit the crane in Vauxhall yesterday morning.
VIDEO: Captain Pete Barnes, pilot of the crashed helicopter, was highly respected by his peers. He was well known an a pilot with the Air Ambulance Service, and was involved in countless rescue missions. We have compiled a short tribute film from ITV News pictures.
London Fire Brigade station manager Bruce Grain, one of the first firefighters at the scene, said it "was absolute chaos" but he revealed the fire was put out within 20 minutes. The pilot was believed to be Captain Pete Barnes from Berkshire.