Hey all, I’m building a 1/24 Brave Borderer from a Perkasa kit which is extremely basic for my ambitions, but I’ll be scratchbuilding and engineering a lot of it.

I wonder if anyone here can tell me anything I can’t find on t’internet about the transom mounted trim flap on these beauties? I can find plenty of low resolution photos, and a description of the angle to which they were set in different sea states, but I just can’t see how they operated mechanically.

There are three exhaust port covers, sometimes called transom flaps (because they’re flaps and on the transom I guess 🤦‍♂️), but those aren’t what I’m wondering about.

Then there’s a shelf below those with a compound curve underside.

Then there’s what looks to be a single, hinged trim tab or flap at the bottom of the transom, which appears to be the hydrodynamic control surface that trims the boat on the plane.

I can see two actuator rods between the shelf and the trim tab, but in different photos the shelf is at different angles, horizontal in this photo. What I don’t know is whether the shelf angle was fixed (what I suspect from the apparent construction) but varied at different periods or between different vessels, or whether this shelf was articulated up and down with the trim tab.

Oh, and judging by the position of the ensign staff holder and the prop handedness, this photo appears to have been mirrored.

Has anyone got any ideas how the trim flap was articulated? Or got any suggestions where I might find out more?