A technical comparison of all the major systems

We put together the following tables (taken from the book Selfsteering under Sail) to give you an overview of all the windvane steering systems that have ever made it into serious production and to help you compare those that are still on the market today.

The first table includes all the different systems that are or have been generally available for purchase and indicates the type, mode of operation and power leverage of each model.

Summary of the 12 types of system

No.

Type

Brand

Country of origin

Vane type

Servo power

Power leverage

Bevel gear

Vessel size

Still in prod.

1 vane only Windpilot Nordsee Ger V no 0 no < 6m/20ft no
2 vane only QME GB H no 0 no < 7m/23ft no
3 auxiliary rudder Windpilot Atlantic 2/3/4 Ger V no 0 no < 10m/33ft no
Windpilot Caribic 2/3/4 Ger V no 0 no < 10m/33ft no
4 auxiliary rudder Hydrovane GB H no 0 no < 15m/44ft yes
Levanter GB H no 0 no < 10m/33ft no
5 trim tab/ auxiliary rudder RVG USA V yes < 25 cm/10 in no < 12m/39ft no
6 trim tab/ auxiliary rudder Auto Helm USA H yes < 25 cm/10 in no < 12m/39ft yes
BWS Taurus NL H yes < 20 cm/8 in no < 15m/49ft yes
Mustafa I H yes < 25 cm/10 in no < 18m/60ft yes
7 trim tab/ main rudder Hasler trim tab GB V yes < 50 cm/20 in no < 12m/39ft no
Windpilot Pacific
trim tab
Ger V yes < 50 cm/20 in no < 12m/39ft no
8 trim tab/ main rudder Atlas F H yes < 50 cm/20 in no < 10m/33ft no
Auto-Steer GB H yes < 50 cm/20 in no < 12m/39ft yes
Viking Roer S H yes < 50 cm/20 in no < 12m/39ft no
9 trim tab/ pendulum rudder Saye's Rig USA V yes < 100 cm/39 in no < 18m/60ft yes
Quartermaster GB V yes < 100 cm/39 in no < 10m/33ft no
10 servo-pendulum rudder Hasler GB V yes < 150 cm/59 in no < 12m/39ft no
Schwingpilot Ger V yes < 50 cm/20 in no < 12m/39ft no
Windpilot Pacific MK I Ger V yes < 140 cm/55 in yes < 14m/46ft no
11 servo-pendulum rudder Aries Standard GB H yes < 190 cm/75 in yes < 18m/60ft yes
Aries Lift-Up GB H yes < 190 cm/75 in yes < 18m/60ft no
Aries Circumnavigator GB H yes < 190 cm/75 in yes < 18m/60ft no
Atoms F H yes < 140 cm/55 in no < 12m/39ft no
Atlas F H yes < 140 cm/55 in no < 12m/39ft no
Auto-Steer GB H yes < 160 cm/63 in yes < 15m/49ft yes
Bogassol E H yes < 139 cm/51 in no < 12m/39ft yes
Bouvaan NL H yes 120-150cm/
47-59in
no < 12m/39ft yes
Cap Horn Can H yes 120-150cm/
47-59in
no < 14m/46ft yes
Fleming NZ H yes 130-170cm/
51-67in
yes < 18m/60ft yes
Monitor USA H yes < 160 cm/63 in yes < 18m/60ft yes
Navik F H yes < 140 cm/55 in no < 10m/33ft yes
Super Navik F H yes < 170 cm/67 in no < 13m/43ft no
Sailomat 601 S H yes 140-210cm/
55-83in
no < 18m/60ft yes
Sirius NL H yes < 150 cm/59 in yes < 13m/43ft no
Windtrakker GB H yes < 170 cm/67 in yes < 15m/49ft yes
Windpilot Pacific Light Ger H yes < 140 cm/55 in yes < 9m/30ft yes
Windpilot Pacific Ger H yes 160-220cm/
63-86in
yes < 18m/60ft yes
12 double rudder Stayer/Sailomat 3040 S H yes < 130 cm/51 in no < 12m/39ft no
Windpilot Pacific Plus Ger H yes 160-220cm/
63-86in
yes < 18m/60ft yes

Key

AR auxiliary rudder system H horizontal axis windvane
SP servo-pendulum system V vertical axis windvane
DR double rudder system WP Windpilot

Windvane type

The vertical or V vane pivots about a vertical axis. Originally horizontal or H vanes pivoted about a strictly horizontal axis, but almost all now have the axis of rotation angled 20 degrees back from horizontal. It is useful if the windvane can be rotated fore and aft in its clamp in response to changes in conditions. A more upright position gives maximum sensitivity for light air sailing, while damping can be optimised in stronger winds by angling the vane back.

Servo power

Servo-assisted systems generate greater steering force

Power leverage

This is a measure of the potential power of a system. The longer the lever, the greater the steering force generated.

Bevel gear

Any system with a bevel gear linkage has automatic yaw damping - oversteering is impossible!

Boat size

Please refer to manufacturer specifications

The tables below compare the major systems on the market today

Technical data of selected windvane steering systems I

 

Operating principal

Windvane

Material

Bearings

Yaw damping by

Instal. weight

(kg/lb)

AR

SP

DR

Type

Angle adjust.?

Windvane

System

Rudder

Aries STD  
+
  H yes plywood aluminium GRP sliding bevel gear 35/77
Hydrovane
+
    H yes aluminium/ Dacron aluminium moulded plastic ball and sliding 3 position linkage approx 33/73
Monitor  
+
  H no plywood stainless steel stainless steel ball and needle bevel gear approx 28/62
Sailomat 601  
+
  H no plywood aluminium aluminium ball and needle adjustable 24/53
WP Pacific Light  
+
  H yes plywood aluminium wood sliding bevel gear 13/29
WP Pacific  
+
  H yes plywood aluminium wood sliding bevel gear 20/44
WP Pacific Plus    
+
H yes plywood aluminium wood/ GRP sliding bevel gear 40/88

 

Materials

We recommend:
- plywood windvanes, since every sailor must be at least somewhat competent with a fret saw
- aluminium castings, as they are light, need little care and can be machined with great accuracy
- buoyant rudder blades, as buoyancy reduces bearing friction

Bearings

We recommend:
- PTFE/Teflon sliding bearings, because they do not seize even after prolonged use

 

 

Types of yaw damping

We refer to any solution based on a 2:1 bevel gear linkage as automatic damping. Some systems have manual damping, where the user manually changes the transmission ratio in response to changes in conditions.

Weight

The less weight you have in the ends, the better your boat will sail.

Technical data of selected windvane steering systems II

 

Remote control

Rudder blade not in use

Possible emergency rudder

Bolts to undo to remove system

Bolts for installation

Wheel adaptor adjustable by

Sizes available

Suitable for vessels up to

Aries STD
+
removable no 8 6 - 8 toothed wheel 1 18 m/60 ft
Hydrovane option fixed or removable yes 4 4 - 6 _ 1 approx 50 ft
Monitor
+
pivots aft yes 4 8 latch pin 1 18 m/60 ft
Sailomat 601
+
lift up yes 1 4 fixed drum 1 18 m/60 ft
WP Pacific Light
_
lift up no 1 4 infinite 1 30 ft
WP Pacific
+
lift up no 1 4 infinite 1 18 m/60 ft
WP Pacific Plus
+
lift up yes 2 8 _ 2 18 m/60 ft

 

Remote control

is best realized using an infinitely adjustable worm gear. The ability to make small and precise course adjustments is essential for good upwind performance. Any system that limits you to large, multiple degree increments will cost you pointing and distance.

What to do with an idle pendulum rudder

The best way to keep a pendulum rudder out of the way when not in use is to lift it up out of the water to one side. All you have to do then to set it back to work is let it swing back down into the water.

Emergency rudder?

As far as we are concerned the only types of windvane gear that can function effectively as an emergency rudder are the auxiliary and double rudder systems. A pendulum rudder is simply too small, too lightly built and too awkwardly fitted to provide anything approaching useful steerage in conditions severe enough to disable the main rudder.

Removable self-steering

You may find it wise in a crowded marina to remove your windvane gear in order to avoid potential collision damage. The easier your system is to remove, the more likely you are to feel comfortable doing this. A readily removable system is also an advantage at the end of a long passage when you need to put the dinghy back in the davits.. 

 

 

How many mounting bolts?

Drilling holes in a boat is bad news - the fewer bolts the better!

Wheel adaptor

We believe the best type of wheel adaptor is a two-part assembly based on the principle of the disk brake. This design provides easy course adjustment and trimming, optimal overload protection (provided the clamps are not overtightened, the drum that receives the transmission lines from the vanegear will slide on the disk in a sudden gust and protect the rest of the system) and the ability to revert to manual steering all but instantly.

Available sizes

All systems offer different shaft length options and some also have different rudder blade sizes.

Technical data of selected windvane steering systems III

 

Pendulum arm axle diameter

Rudder shaft tube dimensions

Rudder profile section

Rudder profil symmetry

Rudder balance proportion

Rudder material

Buoyant

Aries STD

25 mm/ 1 in 38x6.5 mm/
1 1/2x1/4 in
170x50 mm/
6 3/4x2 in
yes 19.4 % glassfibre foam yes

Monitor

19 mm/ 3/4 in 41.3x1.25 mm/
1 1/16x1/20 in
205x46 mm/
8x1 3/4 in
yes 19.5 % stainless/ foam yes

Sailomat 601

40 mm/ 1 1/2 in 50x4 mm/
2x1/6 in
170x25 mm/
6 3/4x1 in
no 20.6 % aluminium no

WP Pacific Light
WP Pacific
WP Pacific Plus

44 mm/ 1 3/4 in 40x5 mm/
1 1/2x1/5 in
120x19 mm/
4 3/4x3/4 in
yes 22.5 % wood epoxy yes