This looks similar to the rudder on my Contessa. That had a block at the top with a bolt through it and a skeg connection at the bottom. When both were taken out it would fall out downwards when the boat was lifted in hoist.
My current Dufour 1800 has a spade rudder that can be lowered out with the boat afloat. (Carefully)
The membership association for owners of Dufour Yachts