asanal wrote on Oct 12^th, 2010 at 7:13pm:

Thanks for your reply. I will make 7 hours test fly and will capture the fuel figures. If my previous figures were right I will not make  my destination Frankfurt. Maybe, if I am lucky Keflavik  shores.. :D BTW why  much difference between 727 and 707 engine_flow_scalar?

You should be fine for a 7 hour flight. My last one was a 8 hour flight with about 95% fuel, and I had about 20'000lbs left after landing.  ;) Fly high and keep the fuel-flow down.