@MartinStrnad -- Oops. sorry, said that 100% backwards, let me re-post. Re aviation.stackexchange.com/… -- on the prototype, both props rotated inward (at top of arc), but on production models, both props rotated outward. The former configuration is actually more favorable for minimizing p-factor in single-engine flight (i.e. if one engine fails), but other factors led to the adoption of the change.