Having had the experience of hitting a reef and tearing a fixed rudder clean off the transom (taking a  bit of the transom with it) I have ever since rather preferred kick-up rudders on shallow draft boats.

(And although there are some distinct advantages to dagger boards, I feel the same way about swing-up centreboards too)

Another advantage of the rudder which Arne and David comment on, is the ability not just to swing up, but to rotate 180 degrees to vertical. The Noelex 22 has this feature, which allows it to be trailered with the rudder instantly out of the way - and with a little hat on top, provides a neat and convenient crutch for supporting the lowered mast. Also, a nice little touch here - note the hardwood plank which gives a little stiffness and weight where needed - and a more durable bearing for the swivel pin. 

Just to add to Arne's/David's comments about scaling this up to a larger boat - on a larger boat where the rudder is trailing a substantial deadwood, the cheeks, if streamlined, can extend down to the bottom of the deadwood, making for a very strong attachment detail (gudgeons, or whatever) and the horizontal stiffener which can be seen here at the bottom of the cheeks, can then also act as an end plate. I am planning something like this on a shallow draft boat with with twin rudders, in the hope that the boat may steer in very shallow water with the blades up.

Sorry to jump in here (off topic, I know) but this rudder design which was spotted by Arne and David is indeed well thought out, and shows some interesting details.

Thanks a lot for the link, Annie.
Although these wet and open multis are not for me, at 59°N, I find the shown rudder designs very interesting, with a better mechanical design than the ones I have seen and used. They would be fine rudders for many small, shallow-draught boats and could easily be turned into aux-rudders for bigger boats. The way they are fitted in the rudder box lets one adjust (increase) the balance until windvanes can control them directly, with no need for servos or trimtabs. The ability to kick up instead of breaking is a bonus.

Cheers,
Arne

Here is a junk rigged, shunting Pacific proa, designed and built by the legendary Tim Mann some years ago in the Central Pacific.  I have not been able to find any details of where the halyards, topping lifts etc are secured, but the double sheets are clearly visible. It obviously works and looks good!  I am beginning to think you can get away with fixed masts if you rethink the position of the masthead crane.  Normally it is angled 30 degrees off-centre on the aft side of the mast, on the same side as the sail is rigged.  That won't wok when you reverse the sail, if the mast is fixed.  But if it was 90 degrees to the centreline, or even angled 30 degrees forward, then there will be minimal twist when the sail is reversed.  Time to make a model!  Click on image to view full size.