l p distance of center of pressure of total lift forward of trailing edge 



l m mean wetted length from trailing edge to stagnation line 



center-of-pressure ratio for total lift 



wetted length-beam ratio 



a x center-of-pressure ratio for lifting line component of lift 



a 2 center-of-pressure ratio for cross-flow component of lift 



b maximum wetted width of planing surface 



'm 



T 



R longitudinal radius of curvature of planing surface 



Z vertical clearance from trailing edge of planing surface to water bottom 



L planing lift 



D planing drag 



M planing trimming moment about trailing edge 



q dynamic pressure — V' 2 



S wetted area 



p water mass density 



V water speed 



a angle of attack of submerged surface with respect to still water level 



Submersion distance of highest point of submerged surface below still-water level 



Aircraft Configurations 



(R + D) total resistance (water resistance plus aerodynamic drag during take-off) 



