Vsplat, welcome aboard, a nice effort for your first post. May there be many more of similar calibre!
As
arrow28 did ask "what are the climb gradients required?" -
1st Segment : Positive climb gradient (Not as bad as it sounds),
2nd Segment : Minimum 2.4% Gross degraded by 0.8% to 1.6% Net, or more as required for obstacle clearance,
3rd Segment : Level, but the aircraft must have the climb gradient capability of 1.2% throughout the level acceleration,
4th Segment : 1.2%
The requirement for a mere "positive" climb gradient for the 1st segment is NOT as bad as it sounds, typical deltas between 1st and 2nd segments are usually of the order of 1.0% or less, thus, as the aircraft MUST achieve at least 2.4% Gross during the 2nd segment, Gross gradient in the 1st segment would be in the 1.4% "ball-park". Again, not too bad, as no credit is allowed for ground effect in the 1st segment during certification, a further plus.
Regards,
Old Smokey