Ok, first, the delta wing is a well proven configuration, very solid, and for high mach speed it doesnt need very poweful engines.

We cant really know about aerodynamics, I must admit, but your small plane seems to have a shape too complicated for such small size, why must have the Fanker/Fulcrum layout for such small plane?, you will save weight stuffing both engines in the same structure, instead putting them on pods, the reason why the flanker has such design is because is more practical for such size, because structural issues for its huge lifting body…but your aircraft is lighter (or it must be).

Flanker/Fulcrum lay out ?

This lay out was also in F-14 Tomcat ( sans variable sweep wing and 4 piece tail feathers )…so compared to F-14 this has only 4 moving parts less…as with the canard fitted Flanker derivatives…compared to Fulcrum Mig-25/35 this has just 2 moving parts less. Also YF-23 is this plane’s big sister ( if you will ).

Where would I put the 2 + 3 concealed missiles if I had a Mirage lay out ?

I added some stealth features in it.

I finally got it right !

F-22 was a tough one to get even with !

I was able to find some interesting info about J-85s from the web;

The J85 engine was originally designed for a maximum flight speed of Mach 2. Engine performance drops off past Mach 2, and increased compressor temperatures approach material limits. In early 1998 NASA Lewis researchers completed a series of tests inside the Center’s Propulsion Systems Laboratory to evaluate the operability of a General Electric J85-21 turbojet engine that they retrofitted to run at Mach 3, 1-1/2 times faster than its maximum flight speed of Mach 2. The tests were part of an overall program, supported by NASA’s Hypersonics Office, to develop a turbine-based combined-cycle propulsion concept that may one day propel aircraft and spacecraft from take-off to hypersonic speeds of more than 5 times the speed of sound. The NASA Lewis concept could revolutionize high-performance aircraft and ultimately make space exploration more affordable by using air-breathing propulsion.

http://www.456fis.org/GENERAL_ELECTRIC_J85.htm

Several variants were produced. The J85-21 variant added a stage ahead of the base 8-stage compressor for a totaltotal[​IMG] of 9 stages, improving thrust.

PLUS; More recently, J85s are used on the Scaled Composites White Knight aircraft, the carrier for the Scaled Composites SpaceShipOne spacecraft, and the aircraft in the US Me 262 Project.

But I also have two of these in mind; http://en.wikipedia.org/wiki/Rolls-Royce_Turbomeca_Adour

You got to lose those thrust vectors, I still don’t believe in 4 engines. You should define the role of the aircraft before you spend so much time on the design.

I can only define it as high speed interceptor or air superiority fighter ! I have no idea how a country like Finland would be able to battle to defend the land without air superiority in case of any bigger conflict.

I think @over-G has it right with regards to basic layout on a small fighter, make it a delta,
but tilted tails has proven susceptible to buffeting at speed.

Another design that would be interesting is a supersonic attack a/c with no trade-offs from rcs & speed going into agility.
I won’t attempt to make a drawing in paint, but an SR-71 body without wings and without tail section,
propelled by a single F119 without afterburner, would be exceptionally hard to catch.

Yes F119 is a very capable engine…you mean like Bird of Prey ?

The ruddervators must indeed be well designed to work.

Ummm, ROLF, yeah, it would seem you are so far behind the curve, you are stuck in the first dip.

I am not Rolf…I am Jukka !

I counted only AC capable to stand even with this ( in the light of the numbers ) is F-22 Raptor !

F-16 could put up without armament ( at very low altitude )..if it ever detects it.

Finally with gear extented !

Dispalyed with my alltime favourite P-38 !

http://en.wikipedia.org/wiki/Lockheed_P-38_Lightning

http://maanpuolustus.net/attachments/p-38_vs-a4sf_55-jpg.1670/

Do you like it ?

It stands 2730 mm tall on the tarmac…just 3190 mm lower than SU-27 ( P-38 Lightning was 3.91 meters high ) .