very good answer i think 😀 , btw can u explain why can’t the Bell x-1 can fly at mach 2.44 with the wing that not swept at all

Assuming Bell X1 has a greater drag coefficient than F-16, it also has a lot smaller wing area (12m2 vs 28m2) and frontal area (8,5m wingspan vs 9,96m), and can result in similar CdA values.

However higher Cd assumption is also debateable, as X1 weighs 5,5 tons (compared to F-16’s ~16 tons) requiring a lot less lift to maintain enough level flight. This can a) lead to a wing with a lot thinner airfoil. b) requiring very little AOA with -generally- higher Lift/Drag ratios. So in the end X1 may be less draggy than an F-16. With a rocket engine which -almost- consistantly produces 26kN output throughout the flight envelope, its also likely to have more thrust than F-16 while flying at M2.0++.

1. reduced weight

Compared to what, and in what terms? F-16 DSI tests showed DSI performs more or less the same as F-16’s normal shock pitot intake. When the simplicity of a pitot intake + diverter is concerned, I really dont think its definately lighter. If you are comparing to a variable inlet; thats in a different weight/performance level and its as stupid as comparing AIM-9 and AIM-120 in terms of weight.

2. cool looks

So when front view is concerned, JF-17 or F-35 looks better than F-14 or Su-27? Thats your -subjective- opinion anyway and has ZERO impact on aircraft performance.

3. ease of construction

So cutting/welding two dozen aluminum sheets just to give DSI geometry is easier than making pitot intake with a diverter plate?

no need for regular maintenance

Same goes for ANY fixed inlet design.

4. reduced RCS by hiding the titanium engine blades without sacrificing aerodynamics as in the case of a purposely built engine blocker

I haven’t seen an intake design that actually block compressor face solely by use of DSI.

The plane with the wing (F-111, Su-24, B-1B, Tu-22M, Tu-160) is able to fly at a height of 30 – 50 meters at supersonic speed. Other aircraft (F-15E, Su-34) no more than M = 0.85.

Wrong. In that very case it is about buffeting which does not allow to keep supersonic speed for more than a brief moment. 😉

In Su-27SK manual it says Su-27 is limited 1400 km/h at sea level with a clear statement that “its not flight mode or time limited”. (if google translator is right). Likewise F-15C is also capable of 800KTAS airpeed at sea level without any appearant time limitation (Same graph does show a time limitation from M2.3 to M2.5) . Those speeds roughly translate to M1.1+ I don’t see why an F-15E or Su-34 cannot do the same.

Not entirely true as the Su-27 is actually less maneuverable than the F-15 when in the supersonic flight realm.

Then thats not entirely true either. If you onlay the STR graphs from their respective flight manuals, you will see F-15 has some advantage only at low supersonic speeds. For example at 30k feet only between M0,92 and M1,62 F-15’s STR graph is above Su-27s. (A negligable advantage of 0,6 deg/s at the most, but still)

The point of my post was to correct a common misconception about the Flanker but as we’re here I have to say I can’t figure out what you’re saying when you said “the fight will take place in subsonic speed regime”, what fight and why would it have to go WVR??? You’ve lost me.

If you look at it this way, MiG-31 is more maneuverable than any other fighter above speeds M2.0+ but no one considers MiG-31 to be maneuverable. I think you are missing my point.

Su-27 dimensions from the flight manual:

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Not entirely on topic but, and I may very well be wrong but, wikipedia article about R-27 it pretty much wrong. IIRC, Avtomatika does not produce IR seekers, and 9B-1032 is the passive seeker head for R-27P/EP variant. R-27T uses Geofizika 36T, which was technologically similar to 60TI on R-60s. It did not have LOAL or HOBS, so it was pretty limited at BVR ranges. On the other hand R-27ET uses the same Mayak-80 seeker on R-73s, and while it still doesnt have a datalink, it does have high off bore sight and lock on after launch capabilities. With ~15 km ranged seeker searching a 45 deg cone, it only needs to get somewhere close to the target to maddog on it, unlike ARH missiles.

There is a pretty clear performance difference between F-16 Block 30 and Block 50.

Here are some graphs I plotted some time ago by using flight manual datas:
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[ATTACH]210232[/ATTACH]

You can see how F-16 Block 50 excels at supersonic high altitude (typical of what is needed at BVR combat), and F-16 Block 30 has better maneuverability both in terms of ITR and STR at subsonic speeds. IMHO, thats a clear shift from CAC oriented design to BVR oriented one.

Sorry for my ignorance.. i did not know there existed pylons on F-16C, F-15C and Su-27 that could be ditched/jettison in flight:confused

I dont know if they exist either. Basically they drop fuel tanks, and pylon is there to cause drag even after jetissoning EFTs.

Pretty straight forward. There is a different in how each jet perform in high speed as well. The F-15 has a slight advantage in the higher speed regime, vs both F-16, Su-27. It will maintain that speed advantage right down to 650km/h even if it cant turn quite the same as F-16 or Su-27.

Thats right, F-15 has different design criterea. A better example is MiG-31; it will out-run, out-accelerate and out-turn any other fighter; but only at a certain area of the flight envelope which is pretty useless at close air combat. So like obligatory said, MiG-31 pilot would disengage before that. Back to your F-15 vs F-16 example; Same goes -to some extent- for F-15. He knows he cant outturn F-16 at low altitude, so maintains a higher energy state be it speed or altitude, try verticals etc etc. Important thing is; thats not because its big; its because designed so.

As for the Su-27, its L/D ratio does it no favor even if it has lots of thrust. Energy loss penalty will rise if you press from STR into ITR. More with the Su-27 than F-16 or F-15.

I have to disagree on that. A more numerical proof is, while Su-27 has lower T/W, it can outturn F-15 at any altitude, below supersonic speeds. That IMHO direcly translates to quite better L/D ratio. However that also means F-15C has lower wavedrag, as supersonic speeds affect the Su-27s performance more.

Higher drag on ITR is possibly because Su-27 can pull (a lot) higher ITR than either types. That doesnt mean its inefficient. For example at 650 km/h, sea level clean condition, Su-27 can sustain 21 deg/s and can pull up to 9Gs and have ITR of 27,8 deg/s. On the other hand F-15C can sustain 18,45 deg/s, and its lift limited to 22,4 deg/s instantenious turn rate. If both are to maneuver at 20 deg/s turn rate, Su-27 will have positive SEP but F-15 will lose energy quite quickly. If both maneuvers at 22,4 deg/s, F-15 would have reached its stall AOA, and would lose energy far more quickly than Su-27. Sure, if Su-27 pilot choses to make a quick 27+ deg/s turn, it would lose a lot of energy; but thats a) not necessary at all b) its still an advantage as its a move enemy aircraft cannot duplicate.

You see, such example as you describe above is not realistic at all.
The F-16C does not go on any regular A2A mission with 3 DT strapped on, no sir. It can rely on tankers.. but really, these are teoretical figures at best.
The F-16C is not designed with a long range intercept role.. good luck with that and three DT strapped on..
The F-16 is not meant to do the same A2A missions as the Flanker, end of story.

Many countries dont have the luxury of operating both heavy and light fighters, so its pretty common for an F-16 goes out to a 800 km patrol. Still, it was a theoratical example anyway. Reality is, there is a reason why all flight manual data is given on 50% fuel.

In such configuration it can easily take off with higher fuel load.

It can, but it won’t. Among other things, mission planners are required to estimate a)flight time/distance to target and back b)loiter/engagment times c)amount of reserve fuel to divert to closest AFB. If a Su-27 takes off for a GAI mission to intercept an aircraft 100 km away, with estimated engagement time 10 minutes, no one is silly enough to fill the tank full. In this situation, it may very well take off with less than 40% fuel on board.

And still have more fuel if in Contact/engagement with F-16C.

That depends on how much distance Su-27 has to cover in order to return to base. Closer it is, less fuel it will have. Same goes for F-16.