Well, at the Saturday press conference two days after the bombing Tim
O'Toole stated that the Piccadilly line tunnel was intact,
specifically in response to a press question as to whther it was
"unsafe." Presumably they did a damage assessment immediately to
determine if it was safe enough to be worked in as a crime scene.

I think the harder issue is how damaged is all the signaling system ie
cables etc. Track is easy to repair, just cut out the busted bits and
bolt in the lovely new shiny bits. As I understand it, the cables used
for signaling are complex, varied and huge in quantity. And then there's
the age of the signaling system. Are there any 'spares' floating around?
or will they have to have new parts made from scratch?


Remember the Camden Town derailment. I think that took about 2 weeks for it
to reopen. Wasn't the main delay there tracing where the damaged cables
went to.