On Tue, 24 Apr 2012 13:12:09 +0100
"Peter Masson" wrote:
4-car formation when they worked the East London Line. But for many years
most units have had an operative cab at one end only, so have been used
exclusively in 8-car formation.

When you say only one operative , do you mean the other didn't work at all
or just didn't have the equipment to be used in passenger service but could
still be used to move the train in an emergency?

B2003