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Hydraulic vs electromechanical ram — which choice for your sailboat?

The essential in 30 seconds

  • ≤ 12 m / 7.5 t: linear electromechanical ram is sufficient. Simple, low maintenance, material 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 still works for cruising, hydraulic recommended for rough seas and offshore. Material cost 2 200-3 500 €.
  • ≥ 15 m / 13.5 t or racing: hydraulic is mandatory. Power, speed, reversibility are essential. Brands: B&G hydraulic T1, T2, Lecomble & Schmitt MK2/MK3, Simrad DD15.
  • 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 excluded installed (ram + computer + sensors + labor), hydraulic 6 500-12 000 € VAT excluded.

The rudder ram is the force actuator 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 of your existing ram, see our article on rudder ram maintenance. For the complete choice of autopilot (ram + computer + sensors), see B&G vs Raymarine autopilot for 40-50 feet sailboat. This article is dedicated solely to the choice of ram 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 connected to the rudder quadrant. Everything is integrated into a single housing: ram = 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 (not currently 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. The pump can be separate from the cylinder (typical for small-medium sailboats) or integrated into a direct drive system (yacht ≥ 50 feet, racing).

Technical comparison: 6 criteria that drive the choice

1. Thrust force

Workshop rule of thumb: 1 000 N per ton of displacement at full load in standard cruising. For offshore racing or heavy cruising in rough seas, increase to 1 500 N/t.

  • 8 t cruising sailboat → minimum 8 kN ram → Type 1 electromechanical or light hydraulic.
  • 14 t offshore cruising sailboat → 14 kN ram → Type 3 electromechanical or T2 hydraulic.
  • 20 t racing sailboat → 30 kN ram → large-stroke hydraulic (DD15, MK3+).

2. Rudder speed (degrees per second)

How quickly the ram can correct a heading deviation. Critical in rough seas and racing.

  • Typical electromechanical: 3-6 s for hard-over to hard-over (35° each side).
  • Typical hydraulic: 2-4 s for hard-over to hard-over.
  • Racing direct drive hydraulic (Simrad DD15, Lewmar GP): 1-2 s for hard-over to hard-over.

3. Electrical consumption

#1 or #2 consumer on the 24 h autopilot energy balance (see our article on lithium battery sizing).

  • 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 (stand-by pump).
  • 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 in peaks but cycles faster and for shorter durations.

4. Reversibility (barman ↔ autopilot ↔ barman transition)

Ability of the ram to free the rudder when the autopilot is disengaged.

  • Linear electromechanical: the worm gear mechanically locks the rudder even with autopilot off. "Braking" sensation for the helmsman, who must push against the internal resistance of the ram. Major drawback in racing and short-handed crews.
  • Hydraulic with automatic bypass: autopilot off = open valves = 100% free rudder. The helmsman takes over without any resistance. This is the criterion that drives 90% of racing programs toward hydraulic systems.

5. Maintenance and lifespan

No major difference if installation is correct. See our rudder ram 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.
  • Racing direct drive hydraulic: more specialized maintenance (seals, pressure, solenoid valve), lifespan 8-12 years in intensive racing use.

6. Footprint and installation

  • Electromechanical: 1 compact housing to mount between structural frame and rudder quadrant. Installation in 4-8 h in workshop.
  • Hydraulic: 2 elements (pump + cylinder) connected by high-pressure hoses. Installation 8-16 h in workshop (hose runs + system bleeding).
  • Racing direct drive hydraulic: complex integration on rudder shaft, installation 16-32 h.

Linear electromechanical ram — 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 rams)

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 ram 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 computer. Skysat distributes the ACU computer and Raymarine accessories; the ram itself may sometimes be ordered as a special.

Lecomble & Schmitt MK1/MK2/MK3

Historic French manufacturer (Vendée). Very common on new Bénéteau/Jeanneau sailboats. Rod stroke 250 mm (MK1), 300 mm (MK2), 350 mm (MK3). Force 7.5 kN to 22 kN. Skysat does not distribute standard but can source on refit project request.

Hydraulic ram — 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 (1 700 €) and T2 24V (2 070 €). Compatible with NAC-3 Navico computer (1 649 €). For sailboats 11-18 m, comfortable offshore cruising and Category B/C racing.

Simrad DD15 (Direct Drive 15 kN)

The DD15 (1 962 €) is a hydraulic direct drive power unit for sailboats 15-22 m racing/offshore cruising. Force 15 kN, hard-over to hard-over speed 1-2 s. Immediate reversibility. Integration requires a dedicated rudder shaft.

Garmin SmartPump v2

The SmartPump v2 (2 899 €) hydraulic pump is compatible with existing hydraulic systems (third-party cylinders). Controlled by the Garmin Reactor 40 hydraulic GHC 50 computer (2 080 €). Good choice for boats already equipped with an original hydraulic cylinder (e.g., Bénéteau Yacht line yachts).

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 Reference type Ram force Installed VAT-excluded budget
≤ 10 m / 5 t Weekend coastal Electromechanical Garmin Type 1, Raymarine Type 1, L&S MK1 5-8 kN 3 500-4 500 €
10-12 m / 5-7.5 t Coastal + 1-2 summer weeks Type 1 electromechanical Garmin Type 1 (1 916 €) + Reactor 40 7.5 kN 4 000-5 500 €
11-13 m / 7.5-10 t Offshore cruising Type 2 electromechanical OR light hydraulic Garmin Type 2 (2 191 €) OR B&G T1 (1 700 €) + NAC-3 10-13 kN 5 500-7 500 €
13-15 m / 10-13.5 t Offshore + transatlantic Hydraulic B&G T2 24V (2 070 €) + NAC-3 13.5 kN 7 000-9 500 €
15-18 m / 13.5-18 t Offshore comfort Hydraulic T2/T3 L&S MK2 hydraulic + NAC-3 15-18 kN 8 500-12 000 €
15-22 m / 13.5-22 t Offshore racing IMOCA/Class40 Direct drive hydraulic Simrad DD15 (1 962 €) + NAC-3 + Madintec 15-22 kN 12 000-18 000 €
≥ 20 m yacht Yacht configured with CZone External pump hydraulic + third-party cylinder Garmin SmartPump v2 + Reactor 40 GHC 50 15-22 kN 10 000-15 000 €
Garmin GHP 12 Type 1 — linear electromechanical ram for sailboat
Garmin GHP 12 Type 1 — linear electromechanical ram for sailboat

Example figures: sailboat 35 / 45 / 55 feet

35-foot sailboat (10.5 m) / 6.5 t — coastal cruising and 2 weeks offshore per year

45-foot sailboat (13.5 m) / 11 t — offshore cruising + 1 transatlantic every 5 years

55-foot sailboat (16.8 m) / 16 t — offshore racing + crewed transatlantic

5 common choice errors seen in the workshop

Ram choice errors — observed at Skysat workshop

  1. Undersizing due to optimism. The sailboat manufacturer lists 7.5 t displacement, so a Type 1 is chosen. Except the boat sails with 800 L of water + fuel + crew + 200 kg of gear = 9.5 t real displacement. The Type 1 struggles, overheats, and eventually fails. Always size on sailed weight, not manufacturer weight.
  2. Choosing electromechanical to "save money" on a 15+ m offshore sailboat. Type 3 electromechanical costs ~1 000 € less than T2 hydraulic. Except in rough seas with 25 knots, the electromechanical saturates, the autopilot disengages, and it's hand-steering 18 h/day. The real savings are negative.
  3. Hydraulic without automatic bypass. If the hydraulic system lacks automatic bypass valves (case of some old kits), the rudder remains locked even with autopilot off. The helmsman struggles, the crew complains. Always verify bypass presence at purchase.
  4. 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 integrates with everything.
  5. Undersized hydraulic pump relative to the cylinder. A 15 kN cylinder with an undersized pump = slow correction, the autopilot lags, oscillations. Always pair pump and cylinder from the same manufacturer or validated together by the installer.

FAQ — Choosing your sailboat ram

Can an existing electromechanical system be converted 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. Allow 16-24 h workshop labor + 2 500-4 000 € material depending on configuration. Only relevant if the boat's program evolves significantly (cruising → racing, or upgrade from coastal to offshore after insufficient experience).

My sailboat already has a Lecomble & Schmitt ram, can I control it with a Garmin or B&G computer?

Yes, the L&S ram is mechanical (or hydraulic) — it accepts any compatible control signal. The computer + rudder angle sensor + compass combination can come from any ecosystem. Verify 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 control almost any ram on the market.

What is 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 B&G/Garmin/Raymarine systems are reversible by default.

Dry or wet hydraulic pump?

Dry pump 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 complete disassembly for maintenance. If refitting, switch to a modern dry pump.

Rudder ram vs tiller quadrant: compatible?

Yes in almost all pleasure craft configurations. The ram drives the tiller quadrant (the part that transmits the rudder rotation to the rudder) via a link arm. Compatibility depends on the quadrant's rotation angle (typically 70° total, ±35° each side), the ram's stroke, and available space. Always verify with a workshop measurement on site before purchase.

Should a backup ram be installed for offshore sailing?

Not a backup ram but a backup strategy: emergency tiller / windvane (Aries, Hydrovane, Windpilot) for sail, or drogue / demountable tiller for power. The electric ram is a sensitive system — in a transatlantic, always have at least a return cable to the manual tiller with the ability to demount the ram-quadrant coupling (typical demountable pin). See our ram maintenance guide for signs of impending failure.

What wiring should be installed between computer and ram?

Wire gauge calculated on max current of ram + 30% margin. Type 1 electromechanical (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): minimum 2 × 6 mm², up to 2 × 10 mm² for powerful pumps. Always protect with a fuse calibrated to the ram's nominal 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 brands. This article reflects our experience installing autopilots on over 120 sailboats between 2018 and 2026, in cruising and offshore racing. 2026 VAT-excluded prices are indicative distributor prices, excluding specific wiring and mechanical adaptation to the existing tiller quadrant.

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