Why rockets dozens of smaller thrusters instead of one giant one?

Question

Why rockets dozens of smaller thrusters instead of one giant one?

In: 6

Answer 1

There are a few reasons…

One reason is that bigger combustion chambers are a little less efficient as the mixing of propellants isn’t quite as good. They can also lead to combustion instability; this was a *huge* development problem with the F-1 engine used on the Saturn V first stage. They ultimately resorted to detonating explosives inside the engine bell to cause instability so they could verify that the engine could deal with it.

This was a big enough problem for the Soviets that they resorted to building single engines with multiple combustion chambers – like the RD-180 used on the Atlas V.

For a launcher like the Falcon 9, a high engine count is required to be able to land the booster after a launch. If it had fewer engines the thrust of a single engine would be too high to be able to land safely.