http://www.wwiiaircraftperformance.o...51d-15342.html
This is the best report you will ever see on cruise performance with external stores, rpm, GW, Hg/boost, speeds, altitudes.
Basic stuff - 9760 pounds GW at take off with full load of ammo, 25 gallons in fuse tank, 184 gallons in main, 21 gallons of oil.
Add two 110 gallon drop tanks = 1490 pounds to get 11250 GW at take off with the loaded drop tanks.
Data at cruise altitude 25K = 281mph, 4.91 miles per gallon, 32 '' at 2250 rpm.
Use ~ 12 gallons for warm up and TO, then another 48-50 gallons to get to 25K over Dutch Coast. If you start with Max GW and 85 gallons, add another 60x5.87#/gallon of gasoline (~6.5 for JP5)-----> 11,600 pounds.
Would take about 2 hours to go straight to Berlin, but essing above bombers at 281mph only proceeds to Berlin at 150 mph IAS for B-17 at 25K (~180mph TAS) -----> maybe 2 hr 20 min from Dutch Coast?
at 4.91miles per gallon at 281mph -----> 57 gallons per hour.
Drop tanks at Berlin if there is a fight, say 25 gallons internally in fuse, plus 184 in mains - the bird would be close to 9700 pounds and 41.6#/sf WL.
Use the Brequet equations if you want more precision .. I haven't checked my math