Your reply is useless due to not being factual as it is inaccurate for several reasons as first is that which J85 are you thinking off since it is original series or that redesign J85-GE-21?
Since Iran did latter and fuel consumption is 1.24lb per lbf per hour and not 0.96lb per lbf per hour that for example Atar 09K-50 on Mirage F1 that Iran has from Iraqis that defected.
Previous J85 used AM355 alloy for compressor blades and multiple disk rotor while J85-21 has them made out of titanium hence despite added axial stage in front of original 8 along increased diameter of inlet that 15 percent increase in weight was negated by 15% increase in dry thrust and 22% increase in afterburner thrust hence greater thrust to weight ratio.
J79-GE-17 in comparison has thrust to weight ratio that is a joke compared to J85-GE-21 that is technologically closer to J79 than is it to older J85 models. Iranian clone of J85-21 is under name Owj has both afterburning and non-afterburning model with latter used on Yasin trainer jet. J85-GE-21 like RD-9 and Atar 09K50 turbojet engines has three bearing with a single shaft/rotor/spool that has 9 axial compressors with annular combustor and 2 turbines.
About year after your atrocious reply to that person is when Iran unveiled Jahesh-700 based on FJ33 medium to high bypass turbofan with key being titanium blades and maybe rotor. Also there is low bypass turbofan that is also single spool with three bearings, a fan and 8 axial compressors and 2 turbines. That is French SNECMA M53 used on Mirage 2000.
Iran could use F-5E/F as platform to gain experience with low bypass turbofans by developing own indigenous design and improve range and velocity of those fighter jets. Afterburner section of J85-GE-21 is longer than core engine, modern afterburner and that for a low bypass turbofan would be much shorter and at least as efficient. Depending on ambition it may well be possible to develop simplicity of M53 with complexity of J79 with technology of J85-21 and FJ33 to develop small good enough low bypass turbofan for F-5E/F that allows supercruising.
1. Are you actually try to correct me and make an arrangement in favor of the J85 by stating that it's fuel consumption is even worse than the figures I gave?
You do understand that 1.24lb of fuel per lbf per hour is more than 0.96lb per lbf/hr.
Are you trying to make my argument for me or do you not understand fuel consumption?
Less fuel better! Not more!
2.My argument was about moving on to the J79 as appose the J85 & not about any other engine! Or Iran's technological capabilities and in fact I clearly state that the J85 is below Iran capabilities and that's why we should move on! So what exactly does the Jahesh 700 have to do with anything. It's an Iranian version of a completely different engine and if anything it proves my point! It's time to move on!
3. Thrust per weight! really?
1st off the vast amount of thrust and air flow you achieve is far more useful on a military aircraft and that negates any negative impact of a heavier engine with higher thrust to weight ratio. And if you want prof just compare the military capabilities of the F-5 vs F-4! It's not even a contest! In terms of thrust to weight a micro jet engine could have a better thrust to weight ratio that doesn't make it a suitable engine for a fighter jet!
These are fighter jet engines not cruise missiles or jet powered gliders!
Also in terms of thrust to weight I clearly mentioned that the J79 are big bulky engines that leave a lot of room for upgrade and weight reduction and that makes it far more suited for upgrades then J85
So for R&D and working on improvements the J79 or better yet the Al-21 are far more suited for the task.
As for the Jahesh-700 yes the Jahesh 700 is a leap in engine designs for Iran and it would make a great engine for UAV's and light trainers or maybe even composite tech demonstrators like the Q313 but it's no fighter engine.
The fact that Iran's developed single crystal turbines is clear prof that Iran needs to move on past the J85 & tiny fighter jet engines in general
And by move on I mean you either design your own turbofan, you copy someone else's (Preferably AL-31) or you grab a viable turbojet and improve on it using modern tech you already have
Iran is NOT a country that going to be producing fighter jet engines at a rate greater than 1 per week be they Al-31's or J85's nor is Iran a country that will ever be producing fighter jets at a rate any faster than 1 per month be they Kowsas or Su-35's at least not in the next 2 decades so I'd much rather go with bigger engines and bigger fighter
Plus with UCAV's blooming force multiplication is key when acquiring new fighters so purchasing or building tiny little fighters with limited capabilities and range is nothing but a waist of money!
