wow that's bizarre. no definitely not correct. i just posted the update. i also updated the a400m example. now the straight blade has the same amount of total sweep. but does it without any blade sweep. this gets rid of the kink. but you loose about 2% propeller efficiency. however, i don't feel like you can really build the bent blades in a way that would perform as predicted. so the straight blade with airfoil sweep is probably the better way to go. i have also been thinking about any kind of sweep and whether or not projecting onto cylinders makes sense. for a purely straight blade with no sweep, so chord distributions 1 and 2, the idea of projecting onto cylinders makes sense. but once you add sweep, i'm not sure it applies anymore. so i just wanted to make sure you had the option to apply the projection or not. you'd have to build and test to see how they work.

for the bug you found with rail points, can you provide the file or example you ran. i mainly need to know the number of points to define the blade, the mesh density multiplier, and the number of tip steps. that way i can see what you are seeing. but definitely sounds like something is messed up there.

besides updating the a400m example, i found a bug in opt that was changing one of the tolerance values. i changed one of the optimization criterias slightly as well. so it's now working the way i expected it to. both input files for the a400m changed. the bug was causing the shaft power target to be voided. now both blades are drawing the specified shp.