Yes, what is proposed is roughly the modification that we had considered for the UAE when we did not yet know the excellent performance of the RBE2, the Rafale radar, and we were trying to gain 10% in range by improving heat extraction. It was proposed to change the cooling circuit pump, which made it possible to increase the peak power of the radar from 10 kW to 14 kW, which allowed a 10% gain in range. But by doing that we were using the margins of the cooling circuit which meant that we were then blocked.
In addition, my linked article focuses on the thermal fuel management system which is the most problematic, but it's not just that!
We already knew that to run Block 4 of the F-35 correctly, you needed Tech Refresh 3 or TR3. We know that TR3 includes software and hardware upgrades to improve displays, memory and computer processing power, we also know that this development increases power consumption and the need for cooling. Unfortunately the F-35 is a little short on electrical generation and cooling, which means that we are already above the initial specifications, particularly for cooling where the thermal management system takes more air than expected, which means operating the engine at excessive temperature which will wear it out prematurely. For electrical generation it is not much better since we learn that we cannot operate all the systems of block 4 at the same time due to its weakness.
It must be understood that the problem is due to a bad design, itself due to a bad specification, because in order of magnitude an electric generation of a fighter is peanuts in energy compared to what is available for the propulsion. That is to say that if it was well designed the thrust would be a little weaker but so insignificant that we would not even feel it in the performance.
So the US says to itself that if we improve the performance of the reactor by changing its core (it's easy because since the time the development of the F-35 has dragged on, there has been technological progress in this area) and If we make a new thermal management system to a good specification we should be able to solve the problem.
But for these modifications to be fully exploited, it is necessary to improve electrical generation, that is to say take more energy, which leads to a new gearbox, and a replacement of the electrical generator which will be part of an overall modification of the electrical power system. Likewise, the evolution of the thermal management system (the one which draws air from the engine) will be accompanied by an evolution of the fuel thermal management system.
So the modification is:
- Software upgrade
- Screens
- Memoirs
- Processors
- Reactor Core
- Gearbox
- Electric generation
- Thermal management system
- Thermal Fuel Management System
Well, it seems that it is not cheap, for an approximate evaluation we are in the order of magnitude of the price of the entire Rafale program.
Oh yes, it will be necessary to retrofit more than 1000 F-35s, including Australia's 72.