F-35 flight control system

[Sentinel Chicken]

I had read that the F-35 has a decentralized hydraulic system but that it's not even a true hydraulic system at that. Catching what snippets of information I could get from Google, as I understand it it uses "electrohydrostatic" actuators that are driven by electric motors and the true centralized hydraulic system that is there is more for the operation of the landing gear?

I also get the impression from the pace of the expansion of the flight envelope that there must be other new technologies in the flight control system as well?

 

[elmayerle]

The answer to your questions is "yes" on all counts. There are a number of interesting technologies used, not just in the flight control system, but throughout the aircraft; I'm just not certain how much I can say about what.

 

[Sentinel Chicken]

From what I can remember reading, the data bus (I'm hoping that's the right term) not only supports the flight control system but also the weapons interfaces and systems and that was something new as in previous aircraft those were different sets of wiring, correct?

EDIT: What I mean to say is that there's a greater degree of avionics integration than on any other aircraft, perhaps even the Raptor. There's one system for weapons, systems, sensors to communicate instead of each having its own dedicated wiring.

 

[elmayerle]

Yeah, very heavy avionics integration, both in regard to systems integration and processing integration.

 

[Mike Pryce]

Regarding avionics, F-35 uses (IIRC) central processing for most functions. In the past each black box could have its own processor(s), of different types and using different software. They would then use a common communication standard (1553B) to pass data around. Now the intention is to centralise data processing in racks of common processor modules using commercial technology where possible, allowing easier hardware/software updates. The radar, EW etc. are 'dumb' and act as peripherals to these central processors. The F-22 has such a system too (ICNIA/INEWS/PAVE PILLAR?). A real pioneer in this area was the Beech Starship, and many biz-jets use similar architectures for their avionics.

The hydraulic system you have right - small electrically powered pumps/reservoirs at each main actuator, plus a lesser 'system' for undercart etc. This is not new in concept (the British V bombers and VC.10 airliner used this idea) but is new in being packaged for a fighter.

All of this is in various 'Sweetman-style' publications on JSF, so is 'public'.