John Cook wrote in message . ..
"I will start with the ferry range as this is the easiest.

The EF2000 can fly 2000 Nm (Nautical Miles) using 5700 litres of fuel
+ 2 x 1000 litres drop tanks, total 7700ltrs , this gives a figure of
3.85 ltrs per nautical mile for an engine that produces 120kN dry
thrust.

This figure does not include any reserve fuel, but as all aircraft
usually have this margin, it can for this purpose be ignored.

But now we have established a fuel usage figure for ferry range for a
120kN class engine.

Sadly, this is not how one calculates range for aircraft. The "liters
per mile" is not constant, but rather a function of specific fuel
consumption (fuel consumption / thrust), lift/drag (dependent on
speed, altitude, and weight), speed, and weight fraction (wet weight /
empty weight).

According to aerospaceweb.org, the Eurofighter has a dry weight of
9750 kg and an internal fuel capacity of 4000 kg (weight fraction of
1.41) while the F-22 has a dry weight of 34000 lb and an internal fuel
capacity of 25000 pounds (weight fraction of 1.68). Range is
proportional to the logarithm of weight fraction, so assuming that
lift/drag are fairly similar and that the engines are of comparable
technology, the F-22 should be able to cruise 50% further on internal
fuel than the EF2000.

Using 2x1000L drop tanks raises the EF2000's weight fraction to 1.55,
so the F-22 should still be able to cruise 17% further disregarding
its lift/drag advantage (no external tanks).

-jake