for RD-93, the max thrust without afterburner is

[email protected] kg/(kN·h), and

[email protected]/(kN·h) fuel consumption rate

That means a 2250kg/h fuel consumption for each engine at full thrust. For twin-engine J-XY it's a doubled 4.5t fuel/h.

Let's assume the engines consuming would be average 80% of max fuel consumption rate during an operation, then it's 3.6t fuel consumption per hour.

Suppose the combat range is 1000km with a 20 minutes stay at the battle field, then a standard operation would take an about 2.5h interval. Then the total fuel consumption would be 9 tons.

With 12.5t empty weight and 25t MTOW and 9t fuel consumption/2.5h operation, the J-XY would have 25-12.5-9=3.5t max payload left, with the weight of the pilot and necessary redundant fuel included.

This is not a very impressive number.