All control surfaces induce drag in operation.
The reason the grid fins are 1cm this is appropriate for its size to generate enough mechanical force to change the attitude of the rocket.
The fact they are 1cm thick is not evident that they are used to slow the rocket down. That is the booster’s responsibility. The controls fins, control the rockets attitude just as the R-77.
They are tapered because slowing the rocket down is not its responsibility nor is it effective whatsoever in slowing down a massive rocket of its size in reentry.
Again, the grid fins of the R-77, Russian ICBMS & Falcon 9 all have the same precise operational use.
This technology was invented by the once great & feared Soviet Union & is still obviously in use today.
The valleys are necessary because of how thick it is to break up wave drag issues, the R-77 doesn’t use them because cost is already high to manufacture with the ultra thin blade like fin tips.
Its surviving in the private sector. You have no experience in the real world. Let me know when you get out there.
I swear I will give you the respect you deserve when you actually make it. You want to bring up my life outside of education. Well then you are acutely aware I have overcome many things in life and are successful to say the least. Get out there & show me.
Cool, so as it is said the RD-180 was never used on a SpaceX rocket and the SpaceX stuff is entirely designed and produced in the US. There are no Russian parts or pieces ever used by the falcon 9.
Touching back with the reason this was brought up - the R-77, the grid fins are ultra thin at the point and are designed for reduced drag whereas the falcon 9’s are optimized for higher drag to stabilize and slow down the booster for re-entry.
This doesn’t need further explanation, the two are not the same. The falcon 9’s are easily optimized as air brakes and a method of slowing down whereas the R-77’s are optimized for high controllability and reduced torque requirement while maintaining high precision. In both designs it reduces cost and in the case of the falcon 9 there are no compromises. For the R-77, the compromise is transonic wave drag. It is far more efficient to launch at above mach, and this is more easily done now thanks to super cruise capable fighters.
The grid fins may be disappearing due to the requirement for missiles of the future to be low observable as well as the fighters. One benefit that was never truly realized on the R-77 is that of foldable grid fins, being that they can fit more in a smaller space such as an internal weapons bay.
Anyhow, if I recall correctly the maximum R-77’s is 12-16 depending on future Sukhoi variants. I’m excited to see them implement the dual racks on the belly between the nacelles.
Did Space X make their own rockets from the begining? No.
So, what government did they contract with for their missions? The US.
What Rockets did the US employ? The Russian RD-180
At the end of the day. The fact remains that Russian ballistic rocket designs are amazing.
They are used by the US today & Elon Musk even concedes to that.
You changed the goal post to “Russian parts”.
Space X produces its own rockets now.
But the very grid fins they use now were invented in The Soviet Union.
It is very Russian regardless if the titanium was forged in Florida or Idaho.
It is purely a Russian design.
No other nation on Earth came up with the design.
I was always right.
Grid fins of both R-77 & Falcon 9 is optimal for Supersonic, Hyper Sonic, High Hypersonic & Reentry speeds, Space X still uses them, Grid fins are not airbrakes, Grid fins are control surfaces, USSR & RuF develop superior rockets, the US uses the Russian RD-180 & Space X used the US for their launches prior to developing their own.
Grid fins on the Falcon 9 are optimized as air brakes to slow the rocket down and have considerably high drag in comparison to grid fins used on the R-77.
To say that anything using grid fins copied Russia is goofy because it’s like saying every single rocket propelled anything is Swedish in origin since that was where the convergent-divergent nozzle was invented. No one goes around claiming every modern rocket with such a nozzle is Swedish-originated.
