Man this is wrong on so many levels.
Firstly when talking about how thrust interacts with stuff that’s flying you need to consider momentum not energy.
Secondly since the part about engine choice and jet velocity part makes absolutely no sense whatsoever I’ll try to explain. The reason you want different engines for different speed regimes boils down very roughly into “having as much mass flow as possible while maintaining adequate exhaust velocity”. Propulsive efficiency is higher for engines with high mass flow than with high exhaust velocity, all else being equal, but in reality bypass air in turbofans (especially high bpr ones) have difficulty accelerating enough for high Mach number operations which is why you see turbojets and ACEs being developed that operates as basically a turbojet at high Mach numbers. No you don’t need the jet speed to be equal to the forward motion of the plane and I don’t see how that even works unless your engine’s mass flow rate equals the plane’s mass (in which case P=mv kicks in and ensures the momentum from the exhaust equals the momentum of the aircraft except it’s still not correct because the freestream velocity hasn’t been taken into account which leads to a bunch of reference frame shenanigans). Also the fact that (for an actual working engine) the jet velocity is higher than the freestream has nothing to do with drag and everything to do with if it’s not exiting at a higher speed then it’s simply not creating any thrust and at that point you might as well build a glider for all the good that engine will do. On top of that I fail to see how the rubbing between the engine exhaust jet and the freestream is part of this conversation as once the jet leaves the exhaust the force (and by extension moment) is imparted onto the jet and what happens after is none of the jet’s business (that is unless you want to go into under and over expansion and how that messes with the pressure field behind the nozzle and how that in turn affects the nozzle behavior but again that’s off-topic).
I don’t want to go into too much detail but other things wrong with this post includes:
there’s supersonic flights and there’s supersonic flightsyou don’t need heat-resistent stuff to go supersonic you need them to go over the heat barrier which neither the B-58 nor the F-15 did (hence neither had titanium or steel or whatever heat-resistant-material skin on the leading edge where aerodynamic heating is most significant)
F15’s titanium structure (frame, skin over engines, also part of the horizontal skin I think) is mainly there because it is stronger than Aluminum at equal weight while significantly lighter than steel at same strength, and it can deal with the engine’s waste heat.
Don’t use sea level thrust for high-altitude calculations because that also makes no sense, let me introduce you to something called a thrust curve. Turns out engines produces different thrusts at different Mach numbers and different altitudes and sea level performance has very little bearing on high-altitude high-speed performance.
Also stop quoting thrust without referring to aircraft size two F100s (or F110s in later models) is absolutely enough thrust for F15’s <30000lb empty weight.
Yes the F-15 absolutely had oversized wings if the definition for “correctly sized wings” is a wing that optimizes supersonic straight-line flight. Again stop quoting random numbers in a vacuum the increase is simply useless here and comparing it to a flanker is somewhat less than useless. If you want to actually know the F15’s performance you probably need exact geometry and a good CFD solver but the gist is that F-15 did indeed use a bunch of design features (blunt-tip airfoils, cranked wing, low wing loading, etc) to make sure that it can generate absolutely massive amounts of lift and maintain a pretty good L/D at high AoA, and naturally the consequence for this is more CD0 which means it’s a bit less efficient at cruise. This is done by all 4th gens and is arguably one of 4th gen fighter’s defining characteristics but that’s off topic.
no one’s saying that but all else being equal, a more draggy wing at cruise condition means the total drag at cruise is higher. It’s not rocket science (literally) and since the wings generate a significant amount of lift, even a small reduction in L/D leads to pretty substantial increases in drag.
Now that I’ve established you really don’t quite know what you’re on about let’s stop this nonsense and get back to what this thread is actually about.
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