So called Rafael killer just a avionics upgrade for blk2? Lol I was expecting more, just like any other Pakistani chest thumping it ended up as usual paper dragon, they added 3 Axis fbw and an aesa called blk3 where mk1a come with all these features plus bouns ones and no one there to take it, least we have to learn from them , if ur home grown product is not up to tire one u have to give a go to it I short term it make difficult but in long run it will help u
3 axis FBW is pretty much useless in JF17
3 axis FBW full potential is realised with unstable aircraft designs only.
That is RSS ( relaxed static stability ) design where the aircraft is designed to be unstable during flight.
Almost all recent 4 and 5 generation fighters have RSS based design.
In simple words the aircraft is designed to be aerodynamically unstable.
RSS changes the dynamics of the aircraft while dramatically enhancing its maneuvering capabilities.
Implementing relaxed static stability means that the center of lift will forward of the center of gravity instead of aft of it and as a result the aircraft will be statically unstable.
Also static stability is proportional to the control forces, therefor reducing stability gives pilots more response for the same effort.
RSS is also called reduced static longitudinal static stability. longitudinal static stability can be measured as the relative distance between neutral point and the center of gravity.
An aircraft with RSS design will have the center of gravity aft of the neutral point. (the neutral point is that point along the path of the center of gravity movement where the stick force per knot drops to zero and increases in either direction.)
As we shift the center of gravity aft of the neutral point , stability is lost and the aircraft will start deviating from its trimmed state.so shifting the center of gravity back gives us a more responsive and maneuverable aircraft but with the added risk of uncontrollable behavior which cannot be contained by manual input. however this behavior is useful if we want high angle changes and even high AOA quickly.
An unstable aircraft only needs minimal kick and will do the rest of the maneuver all by itself. it is also helps to reduce the inertias particularly around the role axis for a faster response.maneuvers are instantaneous initiated and most importantly precisely controlled.
Also deliberately designed unstable aircrafts require smaller control deflections to initiate maneuvering , as a result drag and control surface imposed stresses is reduced and aircraft responsiveness is also enhanced.
RSS configured aircrafts are near impossible to control by pilot input, so an artificial stability is imposed by using computers , servos and sensors as parts of a fully digital fly by wire (FBW) control system working in all the three axis that is pitch, yaw and roll.
And F16 is the first aircraft in which rss was implemented and to control the resultant unstable characteristics of F16 , the concept of digital fly by wire (FBW) was also for the first time implemented in F16.
Advantages of RSS design coupled with FULL FBW are
1.it provides good handling capability
2.it also provides invariant response with respect to variations in aerodynamics , fuel etc and facilitates robust performance.
3.it enables the pilot to fly the mission without worrying about exceeding of flight parameters beyond the safe limits.in flight safety is increased.
4.precise response control , reduced lag and overshoots results in vastly improved response and tracking accuracy of the pilot airframe system.
Also RSS design based aircrafts with tri/quad redundant digital FBW can implement additional highly redundant fail safe advanced safety modes like
1. auto low-speed recovery (ALSR) incase of impending stall during nap of the earth missions or low speed maneuvers etc. The aircraft automatically takes control and recovers the aircraft.
2. Disorientation recovery mode (DRM) to fight pilot disorientation in the high seas ( a common cause for crash at sea ) or in the clouds etc. When the Pilot gets disoriented in such situations, he can press a switch (panic button) provided in the cockpit then the aircraft takes over the controls and recovers itself to level flight optimally (with minimum loss of speed or altitude).
Etc
And FC1/JF 17 is a fighter aircraft whose base design is aerodynamically stable, that is - its design is not rss based.
And the reason why FC1/JF17 came out with analogue flight controls and later a hybrid flight control system and then later according to news reports the JF17B twin seater came with full digital FBW .
The advantages of implementing FBW in a aerodynamically stable aircraft is minimal except for a slight reduction in size , weight and power (SWaP) parameters. It will not increase the aerodynamic performance , superior handling capabilities , stable invariant response etc as compared to a fighter aircraft with a FBW designed to go hand in hand with its inherent aerodynamically unstable rss design from the design stage itself.
All 4 gen aircrafts like f16 , gripen , LCA , typhoon etc are RSS aka unstable designs.
JF17 is a stable design aircraft much like older generations , 3 rd generation downwards.
Implementing FBW in stable designed like JF17 does not confer any kinematic advantage compared to unstable designed aircrafts like LCA .
Full potential of FBW will never be realised in JF17 only advantage will be in SWaP ( size weight power ) savings only .
