The boost phase of Indian hypersonic missile itself is guided (FNC active) and has a thrust termination port, so it doesn’t just burn to completion. It shapes velocity and trajectory right from the first secs, avoids overshoot and sets up a clean entry into the atmosphere with the right energy state. After that it uses a long burn, high energy solid sustainer, so it can compensate for drag losses and keep hypersonic speed inside dense atmosphere instead of dropping out of it like a glide body would. Heating is managed with trajectory shaping, AoA control, shock layer management and thermal protection materials. Staying in the atmosphere spreads heating over time instead of taking a single peak like a steep re-entry.
The aerodynamics also aren’t what you’re assuming. Those aren’t random fins. The short-span, long-chord cruciform mid-body surfaces generate vortex lift through controlled flow separation which helps maintain lift and stability at high Mach and high AoA. The tail fins handle pitch, yaw and roll, so lift and control are separated. That means it can maneuver without constantly destabilizing itself. Inline fin layout also reduces roll coupling and parasitic drag which matters at high dynamic pressure. Yes, there is wave drag and heating but you still need control authority, otherwise it’s just a projectile.
Perhaps there was an error in my technical terms. You didn't understand it properly.
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Your main issue: Confusing subsonic and hypersonic speeds
The statement "generating vortex lift" is basically not valid at hypersonic speeds.
The principle you described is a typical "rib vortex" - this is used by fighter jets such as F/A-18 and Su-27 at low speeds and high angles of attack. But at hypersonic speeds (>5 Mach):
1. The vortex will be compressed by the shock wave: At 5 Mach, the airflow will form a close-fitting oblique shock wave, and the leading edge simply cannot generate the stable vortex that he described. This is like trying to blow a stable soap bubble under a waterfall; it is physically impossible.
2. The vortex lift ≈ 0: Even if a little vortex is generated, it is overwhelmed by the huge shock wave resistance and wave drag. At this point, the so-called "lift" is actually compressive lift (where the shock wave "pushes" the aircraft up), rather than lift generated by the vortex.
For instance, using a "wooden paddle for rowing" as a "propeller". The wooden paddle does generate thrust when moving through water (at subsonic speed); but if he wants to rely on "vortex lift" at hypersonic speeds, it's like trying to use the wooden paddle as an air propeller and still make it work at several hundred kilometers per hour - the principles are completely different.
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You are half right and half wrong: Regarding shock wave resistance and control
· "Adding small wings to increase wave resistance is worthwhile" - This statement is correct. To obtain control moments, sacrificing some wave resistance is a reasonable trade-off in engineering.
· "The in-line layout reduces roll coupling" - This is questionable at hypersonic speeds. The layout you are proud of, "four middle wings + four tail rudders", is a typical "×-×" layout. This layout has very serious roll coupling: when the ailerons differ, a huge yawing moment will be generated, which needs to be compensated desperately with the rudder. This can be solved by the flight control system at low speeds, but at hypersonic speeds, the control margin is extremely narrow, and it will seriously waste the thrust of the engine.