Apparently the makers of SpaceX didn't learn anything from the Soviets...

[Archae]

Back in the 1960's, the old Soviet Union space program had a rocket as big as the Saturn 5, but it used 30+ engines.

It was called the "N-1."

The first test had it get off the ground, but it blew up.
Engine failures.

Second test, the rocket fell back on the pad, where it blew up again.
Again, engine failures.

The Saturn 5 had 5 big engines at launch.
It never failed.

Now?
SpaceX has a big rocket that uses 30+ engines.
It had engine failures and the rocket blew up.

[Disaffected]

1. Means little.

The Falcon Heavy has 27 engines and it works fine.

I doubt there is a whole lot to be learned from the Soviets in any category.

[Archae]

2. Well, we saw what NOT to do...

One of their cosmonauts cussed out the designers of the spacecraft he was in, all the way down until it crashed.

I'm still leery of rockets that need so many engines, more to go wrong.

[Disaffected]

3. I'm not sure why the choice was for more, smaller engines

rather than fewer big ones. One reason may be that developing a new, bigger bigger rocket engine is a difficult, expensive and time consuming process - may be more expedient to simply use a bunch of what you have (you won't find any large rockets that use a single v large engine instead of multiples).

IIRC, smaller rocket engines are also inherently more stable than larger ones. I doubt very much we will ever see anything larger than the Saturn 5 or the SLS engines.

It mostly depends I guess on how gracefully a rocket engine fails i.e. simply shuts down or explodes. If two or three simply shut down on the SpaceX booster, it is still capable of reaching the intended trajectory. If one or more explode, the results would be quite unpredictable...

[Matthew28]

4. Space x

Needs to copy the saturn 5 that worked and go with 5 big engines. I realize that they want to do this because in their experience it works and a bigger rocket is something new if they want it to be reusable but I don't see why it couldn't work.

A bigger and reusable form of saturn 5 would be awesome.

[LastDemocratInSC]

5. Combustion instability was a major problem in the Saturn F1 engines.

The Soviets tried big engines but couldn't solve the instability problems. NASA solved it by adding baffles on the outer side of the fuel / oxidizer injection plate to disrupt the standing waves that occurred when the engine was running. They lost a lot of engines on the test stands to the instability problems; the engines just shook themselves to pieces. The baffles covered the injection plate surface enough that there was a reduction in thrust but that could be offset by running the engines longer in flight.

Here's a good article about the baffles. The first photo shows the baffles on the injector plate.

http://heroicrelics.org/info/f-1/f-1-injector-baffles.html

[yonder]

6. DU is an amazing place.