The booster doesn’t use tbe grid fins except for re-entry and landing.
The grid fins help slow it down from high suborbital speeds and at high angles of attack. This prevents them from needing as much fuel to slow down before landing. Grid fins also require smaller actuators, saving weight. The other benefit is accuracy. The grid fins provide very high precision for ordnance such as the MOAB or R-77, and likewise allow SpaceX to land the booster on a boat in the water.
The use of the fin as an airbrake and to slow the rocket down demanded different grid shape than what is seen on the R-77 which benefits much in the same way - but optimized the grid for low drag rather than higher drag.
In response to a question about the future of American spaceflight, Elon Musk said that Boeing and Lockheed have relied too much on the Russian RD-180 engine.
First of all, you moved the goal post from Russian rockets to Russian engines, proved wrong on both and now you’re saying we use Russian stuff in general at an even lower level… We were talking about SpaceX. They don’t use Russian equipment. They designed their own.
After relying on Russian-made rocket engines for national security launches since the early 2000s, the United States is preparing to blast off with next-generation engines made within its borders.
United Launch Alliance — a joint venture between Lockheed Martin and Boeing — and Elon Musk’s SpaceX are gearing up for the first batch of national security launches awarded to the companies in 2020. More than 30 launches will be carried out between ULA’s Vulcan Centaur and SpaceX’s Falcon 9 and Falcon Heavy from fiscal year 2022 through 2027 as part of phase 2 of the National Security Space Launch program, or NSSL.
The upcoming launches will allow the United States to phase out the Russian-made RD-180 — the first-stage engine used to power ULA’s Atlas V rocket.
The RD-180 engine is a dual-combustion chamber, dual-nozzle engine designed and built by the Russian company Energomash. The engine burns a mix of kerosene and liquid oxygen fuel to give it enough thrust for the initial boost phase of flight, said Chris Stone, senior fellow for space studies at the Mitchell Institute for Aerospace Studies.
Good job, it says the US will no longer be reliant on Russian engines. Not a single SpaceX rocket ever used Russian parts or engines or was based on either.
The article says thanks to US rocket development from SpaceX & others they can drop rockets utilizing the RD-180… None of which are produced by SpaceX.
According to a spokeswoman for United Launch Alliance, the joint venture between Boeing and Lockheed, they have enough RD-180 engines on hand to complete current Atlas V space missions for their customers. The RD-180 is a Russian-made engine used on the Atlas V rocket.
SpaceX faced an opportunity when sales of Russian engines were halted. They were able to design and manufacture their own rocket engines. This gave them an advantage over their competitors.
The switched over no more reliance on the US government contracted Russian RD-180
