Topic summary
Octaweb
Extracted from the Wikipedia article Falcon 9 v1.1.
Modifications from Falcon 9 v1.0
The v1.1 booster version arranged the engines in a structural form SpaceX called Octaweb, with eight engines arranged in a circular pattern around a single center engine. The v1.0 used a rectangular pattern of engines. The Octaweb pattern was aimed at streamlining the manufacturing process. Later v1.1 vehicles include four extensible landing legs, used in the controlled-descent test program.