So you are saying that a Navy Frigat doing 35 knots with its twin 10.000 HP gas turbine engines at full throttle (expending just over 1 liter fuel per second) is in planing mode ?
Speed itself doesn't determine wether you plane or not. The hulls shape has to be designed to go up on a plane otherwise you pretty much stay in displacement mode.
Remember the very old assie 18 skiffs ? Before the introduction of the planing hulls ? Same sailarea and still they couldn't get up to a plane.
Wouter
Hull speed of a 450 ft LOA FFG-7 class frigate is going to be about 27 kn. Published max speed for the FFG is 29 kn, so not planing.
However, a 40 ft cat (hull speed 8.5 kn) at 30+ kn is not acting as a displacement hull and if it's not planing, then it must be in the "fourth mode."
