I read an estimate of 80 tonnes from somewhere* ... and a picture being retweeted (supposedly of BA25 dumping fuel) can be seen via this link:
bit.ly/16vsKUO §
Edit:
*per @jrflight on this search: https://twitter.com/search?q=%23BA25&src=hash
§ not wholly convinced about authenticity of fuel dump photo - it looks like a 744 wing, and the apparent date and time of pic is about right, but those particular properties appear editable in my downloaded copy!
Last edited by slip and turn; 5th Aug 2013 at 22:08.