From
http://www.pprune.org/forums/archive...p/t-76314.html
Fuel for the flight became the critical factor. Fuel weight is limited by tank volume, but if we could somehow make the fuel more dense then we could carry more weight of fuel and it is mass flow that affects the engines. We investigated the possibility of chilling fuel, as this would increase the density slightly. But how to chill 60000 USG and would the effect of cooling be enough? Where could we get some dense fuel? So the search began. Someone suggested we use JP10, an increadibly dense synthetic fuel used by military for some missile applications. That was no good, Boeing advised, the wing structure is not designed to carry that kind of weight and besides, the winglets of this aircraft are not fitted with outrigger wheels. The search went on.
A slight increase in fuel quantity could be achieved by overfilling the fuel tanks. Normally the fuel tanks are never quite filled, to leave some airspace for expansion and prevent fuel spillage if it warmed after fuelling. By overriding the volumetric ****-off of the fuelling system, we could overfill the tanks by about 500 USG. We knew at least on airline used this procedure on a regular basis, provided fuelling was completed just prior to departure.
We kept paring weight out of the aircraft. Alll normal galley equipmet not required on the flight would be shipped to Sydney via Los Angeles. Safety equipment, except the amount required for the actual passengers on board would also be shipped. The same would apply to any cargo restraint equipment. The holds would be empty. The operating weight of the aircraft came down and the range capability edged up.
We started to run actual plans through our flight planning computer. We were tantalizingly close. The fuel for the flight was critical. The search went on......
Approaches were made, quietly, to various oil companies in Europe to see if they could produce the fuel we needed. One after another they said no. Even if they had the deed stock they would need to crack such an exotic brew, the 60000 USG we wanted was either too small or too large an order, and the price would be horrendous.
The fuel was all we need now to make this flight theoretically possible, but time was running out. The aircraft delivery date had now been fixed for the 9th of August. We would soon have to announce our intention and to seek the cooperation of ATC over Europe to expedite the flight and ensure we would be able to get our required route and altitude. Lower than normal altitudes would cause excessive fuel consumption and that could terminate out attempt in the very early stages of the flight. The achieved altitudes in the first two or three hours of the flight would be critical.
Because the flight was one off, we also had to obtain everflight clearances from all the countries over which we would fly, and that can take around 30 days. We needed that fuel. ***** *******, our fuel director felt his telephone bill would keep OTC going for many years.
Behind all this was some doubt about how the aircraft would actually perform. We would not know until we flew it across to London and actually measured its performance. One percent in fuel mileage could make the difference, and that kind of variation from aircraft to aircraft was not unusual.
Finally Shell said they could make the fuel. At last! We could now announce the flight and start real preparations. Shell then said they would move to make the fuel in West Germany because that was where the feed stock was. How would we transport the fuel to London? Tankers we said. Not that easy they said, we dont have them to spare. Another hurdle. Then we found some tankers, not the usual behemoths, small ones, but tankers nonetheless. Nine would be required.