In another StackExchange Physics question, @Rego had found the following equation to calculate the lift force generated by a simple rectangular blade.
$$F = \omega^2 L^2 l\rho\sin^2\phi$$ in which $\omega$ is the angular velocity, $L$ is the lenght of the helix, $l$ is the width of the helix, $\rho$ is the air density at normal conditions, and $\phi$ is the angular deviation of the helix related to the rotating axis. So a 4-helix propeller would lead to $F=4\omega^2 L^2 l\rho\sin^2\phi$ and so on."*
So when substituting the variables with the real values, he obtains this.
However, when calculating this, I get $239.631...$. What steps have been taken between the result of this calculus and the Newton value he ended up with, and why ?