Sunday 11 March 2012 11.07am
I walked up from Kennington to Lower Marsh
about this time and saw it. It appeared to be directly over Waterloo station and, as you say, it had a cable or something hanging from it. At a guess it was lowering something in, possibly to do with the building works there, but by the time I got close, at around 10 to 12, it flew off.