New research into so-called bomb-proof railway carriages seems to offer intriguing possibilities for the next generation of tube trains. Scientists in Newcastle carried out a three-year investigation following the 7/7 attacks in London and the Madrid bombings in 2004.
The engineers conducted a test showing how a standard train carriage would be affected by a bomb blast.
They then tested an adapted carriage which was designed to be more resistant to explosions.
The researchers believe simple modifications could improve the chances of surviving a future attack. Newcastle University's Conor O'Neill said: "Preventing flying objects is the key."
The scientists recommend the use of energy-absorbing materials, plastic coatings on windows and more secure ceiling panels.
However, the response from London Underground appeared to be lukewarm. LU manager Geoff Dunmore suggested: "It is unlikely that a totally bomb-proof carriage could be developed".
The Newcastle team looked into dividing carriages with panels which absorb energy to reduce the impact of a blast. But London Underground has opted for an open-plan design on its new train fleet.