Less is More

If the keel is a low aspect ratio keel and the rudder is directly behind it, then the rudder works in a very deflected flow: a big downwash, which here should be called side/downwash

 

0.8 means that the Rudder lost 80% Angle of Attack

For example

Yacht Yaw/Leeway 6°

Hull (mister Max Michael Munk) Angle of Attack 6°

Keel Angle of Attack 6°

Rudder behind a low Aspect Ratio Keel Angle of Attack 1°

 

(Thomas Harrison Butler)

In a classic yacht, when yawing, the lateral water pressure moves aft, balancing the yacht.

In a modern yacht, this doesn't happen, and the combination of Munk's Moment (Hull hydroDynamic Yaw Moment) + a huuge lateral force of the keel forward (!) of the Yaw axis, and a rudder that is constantly being forced to move can be disastrous ... and if on top of all ... the bow sink ...

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Modern Yachting

Dressed in a €1000 jacket, and for a fortune you have the enormous privilege of being the head of maintenance of an insufferable caravan with sails, and being your brother-in-law's chauffeur.

 

60-foot IMOCA (about 15 years ago)

Sail Carrying Power
% Displacement

60-foot IMOCA @ 15° Heel: 19%
599 @ 15° Heel: 15%
470 Dinghy: 27%

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A Dinghy: 19% - 27%



470 Dinghy: 27%

(Frank Bethwaite)

 

Note two things:

First, with a 15° heel, the plywood epoxy boat rises more than 1.4 (!) meters in height. Compare this to a Dragon or a Tumlaren, which sailed in the water instead of on top

I mean, with 25 knots of wind, the Aero Drag is significant

Second, note that in these types of light boats, controlling the Heel is crucial to prevent the centerboard root from showing out of the water and/or more interactioning with the hull wave

(The position of the 3-in-1 system—mainsailsheet, vang, and preventer in a 2 meter (!) traveller—clearly does not correspond to the wind coming from the starboard side. This position is for Downwind)

With two rudders, the upwind rudder is raised and the downwind rudder is lowered. The difference in induced drag is enormous compared to a heavy yacht with a skeg.

(Water Ballast Tank):

 

(Blue Storm 800)

BLUESTORM 800 8 metre centreboarder by Keith Callaghan https://www.bluelightning.co.uk/ts/BS800.shtm

The old sailor's position is similar: seated forward of the enormous traveller, not behind it. In my case, the boom reaches all the way to the transom.

My antennas are fewer: AIS B+ (5 W) at the very top of the mast

7" KP-27A with AIS Transmitter/Receiver. https://avesmarine.com/7-kp-27a-ais-transceiver

VHF aft on the starboard side

GX1410 https://www.standardhorizon.com/product-detail.aspx?Model=GX1410&CatName=Fixed%20Mount%20VHF

and a clumsy radar reflector on the port side.

The material of the Sails: Dacron from Dimension Polyant

Dimension-Polyant sailing https://www.dimension-polyant.com/

Full battens: RBS

RBS Batten Systems https://www.rbsbattens.com/

 

All the steel I save on the deck, because it's a dinghy with the mast 40 cm from the cockpit and it's strictly Verboten forbidden to step on the deck, goes to the rudder, some very exaggerated pieces for a Dinghy.

 

(Flying Dutchman)

A lot of ropes on a sailboat

1 Ton WindSurf Board for an old sailor

Staysail on boom

+ 1 halyard
+ 1 line to tension the luff from below
+ 4 lines for angle of attack: two (port and starboard) duplicated, passing through a pulley on the boom
+ 1 for twist control
+ 1 for camber
+ 2 for reefing
+ 1 for lowering the sail

= 11

MainSail on boom

+ 1 (3 in 1) MainSail sheet, vang and preventer
+ 2 traveller
+ 7 reefs and outhaul
+ 1

= 11

Gennaker A5 on 3 (!) meter Bowsprit

+ 2
+ 1
+ 1

= 4

No BackStay

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+ 1: The line for tensioning the mainsail halyard is missing

The single winch is for raising the massive keel, and in case it's needed for either of the two anchors: the sand/mud anchor (Mantus M1) and the sea anchor (Lalizas)

Sea Anchor (Drogue) | LALIZAS https://www.lalizas.com/products/mob-systems/sea-anchors-drogues/sea-anchor-drogue

The lines for the gennaker and the staysail can also be run to that single winch.

 

Achtung
Caution

Lalizas sea anchors are sized as "drag devices," meaning they are designed to slow down a sailboat that cannot Surf

Remember that this Tiki 21 in these images is using a 2-meter diameter sea anchor:



Nearby was sailing an old MiniTransat just like the one I own; it had no procedure for stopping and remaining safely stationary, and it lost its mast and was rescued by a merchant ship.



Robert Manry removed the rudder and thanks to that his small boat anchored very well in the sea with a canvas bucket

 

I'd like to go back to the discussion about rigging.
I have tried dyneema for 10k miles and ended up removing it. There was a lot of talk about creep, initial construction strech etc but that hasn’t caused trouble.
Was was not talked about and the main reason for removing it was that the stays were going slack when the weather got colder. A big difference between the day time and night time, and even more obvious when changing latitude in a single trip.
I had lashings so it would take a lot of time to adjust at sea.
Not sure if every kind of dyneema does that? Financially I couldn’t try all kind so I reverted to galvanised rigging, now fighting against rust.
I regularly coat the bottom part of the stays with linseed oil. Doesn’t seem to work too well.
You can’t win... well you could with unstayed mast!