@ellenor2000 @docpop I've been in a 747 which did (at the end of a transcontinental flight) a short hop from somewhere like Dusseldorf to Paris with maybe a dozen people left on board. I've never seen a rate of climb like it! - I'm slightly surprised that the SID allowed it!

Yes, that 757 (IIRC) could almost certainly not have taken off from Cambridge fully laden with fuel and passengers. Empty isn't a problem.