http://spacenews.com/spacex-unveils-mars-mission-plans/
what/who convinced Elon that to go for 42 engines in stage 1 makes sense?
Reusable en plus! Could it be developing F1 size motors is beyond the SpaceX
budget or capability?
Will SpaceX go for Korolev's N-1 rocket, the disaster design? N-1 had "only"
30 engines in stage 1, not reusable.
Instead of going for 40 H-1 (the Saturn 1B engine) the number required for
the 35000 kN Apollo thrust, NASA chose the hard way of developing F-1 of
which only 5 sufficed in the first stage.
jd
