I understand the points of some members regarding F-35 but all accusations have a natural connection with arrogant policies of US, not about tech. In fact, If we put politic cards out of the subject, I believe Majority of members will approve that US is the most advanced nation in aviation technology and F-35 is the most advanced and matured 5th generation stealth fighter jet of the World although It has some minor problems that is being fixed in further blocks. No country can come close to the level where US is locating at present. Be it in turbofan tech, radar and stealth fuselage/coating, avionics and self protection systems. In this regard, Russia is nowhere to have a saying in aviation technology If the matter is US. They could not even develop a reliable drone today, while they lack behind in electro-optic, active electrocally scanned array modules and semi-conductors technologies. Besides, It is not a secret new high tech toys like F-35, S-400, drones, satellites are loyal to their manufacturers so If you rely on foreign technology to meet striking/defensive requirements of your armed forces, You should know/consider this risk. I mean S-400 is not an angel while describing F-35 a devil inside TurAF. There won’t be a future like S-400 shot down a Russian Su-35 or F-35 shot down US F-22 so what we should do is to gain knowledge/tech to develop our aviation infrastructure to develop/produce our own competible fighter jets so We should consider the benefits of our industry to select the best programs that will be benefical for our aviation industry (design engineering, manufacturing process, composite materials, titanium/nickel alloy handling, electronic subcomponent productions, stealth tech, offsets, experiences...etc). In this regard, F-35 provides huge benefits worth more than 8-10 billion $ to more than 10-12 institutes but S-400 was a government to government direct procurement project that was selected with purly considering politic requirements instead of industrial benefits so S-400 offers nothing to our industry. In additions, It is a big question whether It can provide capabilities that is written in its brochure so I believe government should re-check the F-35/S-400 policy to care about benefits of our industry and It seems they started giving some signals by not activating S-400 batteries.