Re: New Generation Fighter
So much have been said about the subsonic limitation of DSI, I guess we'll have to hear from the real professionals, other than those internet armchair "experts", on whether there're ways to go around this limitation and whether the DSI inlet design can be optimised towards supersonic performance rather than just subsonic performance.
This is a problem of all fixed inlet designs. A military plane operates in a great speedrange, and aerodynamic condition change greatly along those ranges, especially when going through the sound barrier. Of course a fixed DSI inlet can be designed to favor supersonic flight envelopes with a design aim of say M3. But that comes at the expense of dramaticly decreasing slow speed performance, since the engine won't have enough air anymore. At some point slow speed flight / take off performance will be so bad the whole thing isn't usefull anymore.
Well, thinking about it, it may be possible though to have extra doors installed on the side / top or so of the intake cover that open in the slow speed regimes to allow extra airflow. Like in the Tornado, or the MiG-29 that totally closed the regular intakes for take off.
I'm not yet entirely convinced on the arguments about better trans and supersonic performance. Maybe if someone who supports that view could better explain how being longer helps, I might change my mind.
There's this thing called the area rule. Especially in the transsonic regions a body with a certain shape has the least drag. That body looks like a cigar, but pointed towards the ends. Length and diameter are in a certain relation, since the smoother the diameter / shape change over length, the better the airflow. So to put more volume inside a body, or just make it wider, it has to become longer to maintain the same aerodynamic properties in that regard.
That is probably not the whole truth the planes length, but I guess at least part of it.
I'm sure internal fuel load, hence range is also a factor. And, seeing the shape, maybe the engeniers indeed managed to put a big, continuous weapons by into the fuselage. Not big enough for real AShM, but for some AGM at least.