The essentials in 30 seconds
- ≤ 12 m / 7.5 t : linear electromechanical actuator is sufficient. Simple, low maintenance, equipment cost €1,500-2,200. Brands: Garmin GHP 12 Type 1, Raymarine Type 1, Lecomble & Schmitt MK1.
- 12-15 m / 7.5-13.5 t : Type 2 electromechanical may still work for cruising, hydraulic recommended in rough seas and offshore. Equipment cost €1,800-2,200.
- ≥ 15 m / 13.5 t or racing : hydraulic is mandatory. Force, speed, and reversibility are essential. Brands: B&G hydraulic T1, T2 (complete cylinders), Lecomble & Schmitt MK2/MK3, Simrad DD15 (direct-drive unit, cylinder/integration on rudder stock as an extra).
- Watch the delivered scope: a linear actuator (Garmin, Raymarine, B&G T1/T2) is a complete product — you bolt it to the quadrant. A standalone pump (Garmin SmartPump v2) or a direct-drive unit (DD15) requires an additional cylinder and integration (around €1,500 to €4,000 VAT-excluded equipment + labor) — their list price does not represent the installed system.
- 3 key criteria to decide: thrust force (minimum 1,000 N/t displacement), rudder speed (3-5 s/° in cruising, < 2 s/° in racing), reversibility barman ↔ autopilot (hydraulic wins).
- Full refit budget: electromechanical €4,000-6,500 VAT-installed (actuator + computer + sensors + labor), hydraulic €6,500-12,000 VAT.
Products mentioned: Garmin GHP 12 Type 1 · B&G hydraulic T1 · B&G hydraulic T2 · Simrad DD15 · Garmin SmartPump v2. Details and budget in the sections below.
The rudder actuator is the force organ of the autopilot. It converts an electrical signal into rudder movement. Two technology families coexist: electromechanical (electric motor + worm gear) and hydraulic (pump + cylinder). Choosing one or the other determines 10 years of use, the refit budget, and the relevance of the autopilot in conditions.
If you are looking for maintenance on your existing actuator, see our article on rudder actuator maintenance. For the complete choice of autopilot (actuator + computer + sensors), see B&G vs Raymarine autopilot for 40-50 ft sailboats. This article is dedicated solely to the choice of actuator technology.
The two families: electromechanical vs hydraulic
Linear electromechanical
An electric motor turns a worm gear that pushes or pulls a rod. The rod is mechanically linked to the rudder quadrant. Everything is integrated into a single housing: actuator = finished product, assembled and forgotten.
- Brands on Skysat: Garmin GHP 12 Type 1 (€1,916), Type 2 (€2,191), Raymarine Type 1/2/3, Lecomble & Schmitt MK1/MK2/MK3 (currently not distributed by Skysat).
- Typical range: sailboats 8-15 m, up to 13.5 t displacement, rod stroke 250-350 mm.
- Force: 7.5-13.5 kN depending on model.
Hydraulic
An electric pump pressurizes oil in a cylinder attached to the rudder quadrant. This is where the delivered scope changes everything: some references are complete actuators (pump + cylinder in the product, e.g. B&G T1/T2), others are a standalone pump that requires a third-party cylinder (e.g. Garmin SmartPump v2), and others are a direct-drive unit whose integration on the rudder stock is priced separately (e.g. Simrad DD15). Ignoring this scope distorts the budget.
- Brands on Skysat: B&G hydraulic T1 12V (€1,785), T2 24V (€2,174), Simrad DD15 (€2,363), Garmin SmartPump v2 (€2,416), Lecomble & Schmitt MK1/MK2/MK3 hydraulic (available on special order).
- Typical range: sailboats 11-22 m, offshore cruising large size, multihulls.
- Force: 13.5-22 kN+ depending on configuration.
Technical comparison: 6 criteria that drive the choice
1. Thrust force
Workshop rule of thumb: 1,000 N per tonne of displacement at full load in standard cruising. For offshore racing or heavy offshore cruising, increase to 1,500 N/t.
- 8 t sailboat in cruising (coefficient 1,000 N/t) → 8 × 1,000 = 8 kN minimum → Type 1 electromechanical or light hydraulic.
- 14 t sailboat in offshore cruising (coefficient 1,000 N/t) → 14 × 1,000 = 14 kN → Type 3 electromechanical or hydraulic T2.
- 20 t sailboat in racing (coefficient 1,500 N/t) → 20 × 1,500 = 30 kN → large-stroke hydraulic (MK3+; DD15 tops out at 15 kN).
2. Rudder speed (degrees per second)
The speed at which the actuator can correct a heading deviation. Critical in rough seas and racing.
- Electromechanical typical: 3-6 s for rudder-to-rudder (35° each side).
- Hydraulic typical: 2-4 s for rudder-to-rudder.
- Hydraulic direct-drive racing (Simrad DD15, Lewmar GP): 1-2 s for rudder-to-rudder.
3. Electrical consumption
#1 or #2 consumer on the 24 h autopilot energy budget (see our article on sizing lithium banks).
- Electromechanical at rest: 0.1 A (just logic power).
- Electromechanical in correction: 1-3 A (Type 1) to 3-6 A (Type 3).
- Hydraulic at rest: 0.2-0.5 A (pump standby).
- Hydraulic in correction: 3-8 A peak, but shorter cycles.
Over 24 h in rough seas, total consumption is roughly equivalent between the two technologies — hydraulic consumes more at peak but cycles faster, so for less time.
4. Reversibility (barman ↔ autopilot ↔ barman transition)
Ability of the actuator to free the rudder when the autopilot is disengaged.
- Linear electromechanical: the worm gear mechanically locks the rudder even with autopilot off. Creates a "braking" feel for the helmsman, who must push against the internal resistance of the actuator. Major drawback in racing and short-handed crews.
- Hydraulic with automatic bypass: autopilot off = open valves = rudder 100% free. The helmsman takes over without any resistance. This is the criterion that tips 90% of racing programs toward hydraulic.
5. Maintenance and lifespan
No major difference if installation is correct. See our rudder actuator maintenance guide.
- Electromechanical: 1 greasing of shafts + rod ends per season, bronze bushing check every 500 h, typical lifespan 10-15 years.
- Hydraulic: annual oil level and quality check, drain every 5 years, typical lifespan 12-18 years.
- Hydraulic direct-drive racing: more precise maintenance (seals, pressure, solenoid valve), lifespan 8-12 years in intensive racing use.
6. Footprint and installation
- Electromechanical: 1 compact housing to mount between frame and rudder quadrant. Installation in 4-8 h in the workshop.
- Hydraulic: 2 elements (pump + cylinder) connected by high-pressure hoses. Installation 8-16 h in the workshop (hose runs + system bleeding).
- Hydraulic direct-drive racing: complex integration on rudder stock, installation 16-32 h.
Linear electromechanical actuator — details and brands
The historic technology for sailboat pleasure craft since the 1980s. Widely adopted because it is the simplest product to integrate in a refit.
Garmin GHP 12 (linear actuators)
Skysat distributes the Type 1 (€1,916) for sailboats ≤ 11 m / 7.5 t and the Type 2 (€2,191) for sailboats 11-15 m / 7.5-13.5 t. The actuator is controlled via a Reactor 40 computer and a GHC 50 display.
Raymarine Type 1/2/3
Historic Raymarine Evolution range. Type 1 ≤ 11 m, Type 2 11-15 m, Type 3 15-22 m. Compatible with Raymarine EV-100/EV-200/EV-400 computers. Skysat distributes the ACU computer and Raymarine accessories; the actuator itself may be ordered as a special order in some cases.
Lecomble & Schmitt MK1/MK2/MK3
Historic French manufacturer (Vendée). Widely used on new Beneteau/Jeanneau sailboats. Rod stroke 250 mm (MK1), 300 mm (MK2), 350 mm (MK3). Force 7.5 kN to 22 kN. Skysat does not distribute these as standard but can source them for refit projects on request.
Hydraulic actuator — details and brands
Mandatory technology beyond 15 m, strongly recommended for offshore racing from 10 m. Pump + cylinder + bypass + pressure gauge architecture.
B&G hydraulic T1/T2
Skysat distributes the B&G T1 12V (€1,785) and T2 24V (€2,174). Compatible with NAC-3 Navico computer (€1,731). For sailboats 11-18 m, comfortable offshore cruising, and Category B/C racing.
Simrad DD15 (Direct Drive 15 kN)
The DD15 (€2,363) is a power unit (direct-drive group), not a complete actuator: for sailboats 15-22 m racing/heavy cruising. Force 15 kN, rudder-to-rudder speed 1-2 s, immediate reversibility. The €2,363 price is for the group alone. Integration requires a dedicated rudder stock (adapted shaft/quadrant) and coupling hardware: budget an additional €1,500 to €4,000 VAT-excluded (integration parts + labor), depending on the boat’s rudder. When buying, think in terms of installed system, not list price.
Garmin SmartPump v2
The SmartPump v2 (€2,416) is a standalone pump, without cylinder: its price does not include the actuator. It connects to a third-party cylinder (existing or to be purchased) and is controlled by the Garmin Reactor 40 hydraulic GHC 50 computer (€1,733). It is therefore a good choice mainly for boats already equipped with a hydraulic cylinder (e.g. Beneteau Yacht line): you are only replacing the pump. If the cylinder is to be added, budget an additional €1,500 to €4,000 VAT-excluded (cylinder + connections + installation). For a boat without existing hydraulics, a complete B&G T1/T2 actuator is often cheaper at the system level.
Lecomble & Schmitt hydraulic MK1/MK2/MK3
Separate pumps and cylinders, hydraulic equivalents of the L&S electromechanical range. Widely used in French offshore racing (IMOCA, Class40). Available on special order via Skysat.
Comparison table by size and program
| Sailboat | Program | Recommended tech | Typical reference | Delivered scope | Actuator force | VAT-installed budget |
|---|---|---|---|---|---|---|
| ≤ 10 m / 5 t | Weekend coastal | Electromechanical | Garmin Type 1, Raymarine Type 1, L&S MK1 (special order) | Complete actuator | 5-8 kN | €3,500-4,500 |
| 10-12 m / 5-7.5 t | Coastal + 1-2 weeks summer | Electromechanical Type 1 | Garmin Type 1 (€1,916) + Reactor 40 | Complete actuator | 7.5 kN | €4,000-5,500 |
| 11-13 m / 7.5-10 t | Offshore cruising | Electromechanical Type 2 OR light hydraulic | Garmin Type 2 (€2,191) OR B&G T1 (€1,785) + NAC-3 | Complete actuator | 10-13 kN | €5,500-7,500 |
| 13-15 m / 10-13.5 t | Offshore + transatlantic | Hydraulic | B&G T2 24V (€2,174) + NAC-3 | Complete actuator (pump + cylinder) | 13.5 kN | €7,000-9,500 |
| 15-18 m / 13.5-18 t | Comfortable offshore | Hydraulic T2/T3 | L&S MK2 hydraulic (special order) + NAC-3 | Complete actuator (pump + cylinder) | 15-18 kN | €8,500-12,000 |
| 15-22 m / 13.5-22 t | Offshore racing IMOCA/Class40 | Hydraulic direct drive | Simrad DD15 (€2,363) + NAC-3 + Madintec | Direct-drive group only — cylinder + integration on rudder stock extra (~€1,500-4,000 VAT) | 15 kN (DD15) | €12,000-18,000 |
| ≥ 20 m yacht | Yacht configured with CZone | Hydraulic external pump + third-party cylinder | Garmin SmartPump v2 + Reactor 40 GHC 50 | Standalone pump — only relevant if hydraulic cylinder already onboard; otherwise (cylinder to add ~€1,500-4,000 VAT) a complete actuator is often cheaper | 15-22 kN (depending on cylinder) | €10,000-15,000 |
Example figures: 35 / 45 / 55 ft sailboat
35 ft sailboat (10.5 m) / 6.5 t — coastal cruising and 2 weeks offshore per year
- Recommended choice: electromechanical Type 1 (simplicity trumps power margins).
- Typical config: Garmin Type 1 (€1,916) + Reactor 40 Compact Pack (€1,316) including computer + GHC 50 + sensors.
- Total installed budget: €4,200-5,000 VAT (actuator + pack + 8 h labor).
45 ft sailboat (13.5 m) / 11 t — offshore cruising + 1 transatlantic every 5 years
- Recommended choice: B&G hydraulic T1, for barman ↔ autopilot ↔ barman reversibility (rotating crew) and power margin in rough seas.
- Hardware side: B&G hydraulic T1 12V (€1,785) + NAC-3 (€1,731) + Precision 9 (€702) + RF25N (€319).
- Total installed budget: €6,500-8,000 VAT (actuator + computer + sensors + 12 h labor + oil).
55 ft sailboat (16.8 m) / 16 t — offshore racing + crewed transatlantic
- Recommended choice: hydraulic direct drive with premium racing computer (Madintec compatible).
- Workshop approach: Simrad DD15 (€2,363) + NAC-3 (€1,731) + sensors + Madintec MAD Controller (€2,550) as a racing upgrade.
- The DD15 is a standalone group: the budget below includes the cylinder + integration on the rudder stock (around €1,500 to €4,000 VAT parts + labor), which must not be forgotten — this is what separates the bare group from the truly installed system.
- Total installed budget: €13,000-18,000 VAT (DD15 group + cylinder/rudder integration + computer + sensors + Madintec + 24 h labor).
5 common choice errors observed in the workshop
Actuator choice errors — seen in the Skysat workshop
- Undersizing by optimism. The sailboat manufacturer lists 7.5 t displacement, so you choose Type 1. Except the boat sails with 800 L of water + fuel + crew + 200 kg of gear = 9.5 t real. The Type 1 strains, overheats, and eventually fails. Always size on sailed weight, not manufacturer weight.
- Choosing electromechanical to "save money" on a 15+ m offshore sailboat. Type 3 electromechanical costs ~€1,000 less than hydraulic T2. Except in rough seas at 25 knots, the electromechanical saturates, the autopilot drops out, and you’re hand-steering 18 h/day. The real savings are negative.
- Hydraulic without automatic bypass. If the hydraulic system lacks automatic bypass valves (as in some old kits), the rudder remains locked even with autopilot off. The helmsman struggles, the crew complains. Always check for bypass at purchase.
- Choosing an incompatible brand with the existing ecosystem. The boat has a Raymarine Axiom chartplotter. The client buys a Garmin Reactor 40 autopilot to save money. Result: no autopilot control from the Axiom, Garmin remote required at the cockpit, two parallel ecosystems. Choose an autopilot from the same brand as the main chartplotter — or an open system like Madintec that talks to everything.
- Undersized hydraulic pump relative to the cylinder. A 15 kN cylinder with an undersized pump = slow correction, the autopilot lags, oscillations. Always match pump and cylinder from the same manufacturer or validated together by the installer.
FAQ — Choosing your sailboat actuator
Can you convert an existing electromechanical system to hydraulic?
Yes, but the installation is heavy: new hydraulic cylinder, new pump, high-pressure hose runs, system bleeding, possible modification of the rudder quadrant. Budget 16-24 h workshop labor + €2,500-4,000 equipment depending on configuration. Only relevant if the boat’s program changes significantly (cruising → racing, or upgrading to offshore after insufficient coastal experience).
My sailboat already has a Lecomble & Schmitt actuator, can I control it with a Garmin or B&G computer?
Yes, the L&S actuator is mechanical (or hydraulic) — it accepts any compatible control signal for its rated voltage. The computer + rudder angle sensor + compass combination can come from any ecosystem. Check the electrical interface of the existing L&S (voltage, max current, position feedback type) and adapt the computer accordingly. The Madintec MAD Controller is designed to drive almost any actuator on the market.
What’s the difference between reversible and non-reversible hydraulic?
Reversible hydraulic = double-acting pump (can push or pull the cylinder), requires bypass valves to free the rudder. Non-reversible hydraulic = single-acting pump, the rudder is mechanically linked pump-cylinder when autopilot is off (permanent brake). Always prefer reversible with automatic bypass for safety and helmsman comfort. All modern hydraulic systems from B&G/Garmin/Raymarine are reversible (bypass); linear electromechanical actuators mechanically lock the rudder with autopilot off (see the reversibility criterion above).
Dry or wet hydraulic pump?
Dry in 99% of cases. The pump is mounted in a ventilated technical locker, near the cylinder. Wet pump (immersed in the oil reservoir) exists on some old systems but requires a sealed reservoir and full disassembly for maintenance. If refitting, switch to a modern dry pump.
Rudder actuator vs tiller quadrant: compatible?
Yes in almost all pleasure craft configurations. The actuator drives the rudder quadrant (the part that transmits the rudder’s rotation to the rudder blade) via a connecting rod. Compatibility depends on the quadrant’s rotation angle (typically 70° total, ±35° each side), the actuator’s stroke, and available space. Always verify with an on-site workshop measurement before purchase.
Should you plan a backup actuator offshore?
Not a backup actuator, but a backup strategy: tiller pilot / windvane (Aries, Hydrovane, Windpilot) for sail, or a drogue / demountable tiller for power. The electric actuator is a sensitive system — on a transatlantic, plan at least a manual rudder return cable with demountable coupling to the quadrant (e.g. demountable pin). See our actuator maintenance guide for signs of impending failure.
What wiring should you plan between computer and actuator?
Wire gauge calculated on max current of the actuator + 30% margin. Electromechanical Type 1 (5-10 A): 2 × 4 mm² cable for 3-5 m runs. Type 2-3 (10-15 A): 2 × 6 mm². Hydraulic pump (8-15 A peak): 2 × 6 mm² minimum, up to 2 × 10 mm² on high-power pumps. Always protect with a fuse calibrated to the actuator’s rated current (not peak) + 50%, accessible from the dashboard for quick reset in case of incident.
Skysat distributes B&G, Garmin, Raymarine, Navico, Madintec, and Simrad. This article reflects our workshop installation and after-sales experience with autopilots in cruising and offshore racing. 2026 VAT-excluded prices are indicative of authorized distributor rates, excluding specific wiring and mechanical adaptation to the existing rudder quadrant.
