The essentials in 30 seconds
- ≤ 12 m / 7.5 t: linear electromechanical 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, but hydraulic is recommended for rough seas and offshore. Material cost €2,200–3,500.
- ≥ 15 m / 13.5 t or racing: hydraulic is mandatory. Force, speed, and reversibility are essential. Brands: B&G hydraulic T1, T2, Lecomble & Schmitt MK2/MK3, Simrad DD15.
- 3 key criteria to weigh: thrust force (minimum 1,000 N/t displacement), rudder speed (3–5 s/° in cruising, < 2 s/° in racing), reversibility bar-to-pilot (hydraulic wins).
- Full refit budget: electromechanical €4,000–6,500 ex. VAT installed (ram + computer + sensors + labor), hydraulic €6,500–12,000 ex. VAT.
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, refit budget, and the autopilot’s relevance in conditions.
If you’re looking for maintenance on your existing ram, see our article on rudder ram maintenance. For choosing a complete autopilot (ram + computer + sensors), see B&G vs. Raymarine autopilot for 40–50 ft sailboats. This article is dedicated solely to the choice of ram technology.
The two families: electromechanical vs. hydraulic
Linear electromechanical
An electric motor drives 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: 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 (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. The pump can be separate from the cylinder (typical for small to medium sailboats) or integrated into a direct drive system (yacht ≥ 50 ft, racing).
- Brands on Skysat: B&G hydraulic T1 12V (€1,700), T2 24V (€2,070), Simrad DD15 (€1,962), Garmin SmartPump v2 (€2,899), Lecomble & Schmitt MK1/MK2/MK3 hydraulic (available on special order).
- Typical range: sailboats 11–22 m, offshore cruising or large size, multihulls.
- Force: 13.5–22 kN+ depending on configuration.
Technical comparison: 6 criteria that determine the choice
1. Thrust force
Workshop rule of thumb: 1,000 N per ton of displacement at full load in standard cruising. For offshore cruising or heavy offshore conditions, 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 of autopilot power in a 24 h 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 at peak but cycles faster and for shorter durations.
4. Reversibility (bar-to-pilot-to-bar 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 the pilot off. Creates a "braking" sensation for the helmsman, who must push against the internal resistance of the ram. Major drawback in racing and short-handed sailing.
- Hydraulic with automatic bypass: pilot 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 pins and 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 the workshop.
- Hydraulic: 2 components (pump + cylinder) connected by high-pressure hoses. Installation 8–16 h in the 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 historical technology for sailboats since the 1980s. Widely adopted because it’s 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
Historical 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 is sometimes available on special order.
Lecomble & Schmitt MK1/MK2/MK3
French historical 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 request for refit projects.
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 direct drive hydraulic 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 | Type reference | Ram force | Ex. VAT installed 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 weeks summer | 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 cruising comfort | T2/T3 hydraulic | 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 with CZone | External pump hydraulic + third-party cylinder | Garmin SmartPump v2 + Reactor 40 GHC 50 | 15–22 kN | €10,000–15,000 |
Example figures: 35 / 45 / 55 ft sailboats
35 ft sailboat (10.5 m) / 6.5 t — coastal cruising and 2 weeks offshore per year
- Recommended choice: Type 1 electromechanical (simplicity outweighs power margins).
- Skysat solution: Garmin Type 1 (€1,916) + Reactor 40 Compact starter pack (€1,579) including computer + GHC 50 + sensors.
- Total installed budget: €4,200–5,000 ex. VAT (ram + pack + 8 h labor).
45 ft sailboat (13.5 m) / 11 t — offshore cruising + 1 transatlantic every 5 years
- Recommended choice: B&G T1 hydraulic, for bar-to-pilot reversibility (short-handed sailing) and margin in rough seas.
- Skysat solution: B&G hydraulic T1 12V (€1,700) + NAC-3 (€1,649) + Precision 9 (€533) + RF25N (€319).
- Total installed budget: €6,500–8,000 ex. VAT (ram + computer + sensors + 12 h labor + oil).
55 ft sailboat (16.8 m) / 16 t — offshore racing + crewed transatlantic
- Recommended choice: direct drive hydraulic with premium racing computer (Madintec compatible).
- Skysat solution: Simrad DD15 (€1,962) + NAC-3 (€1,649) + sensors + Madintec MAD Controller (€2,550) for racing upgrade.
- Total installed budget: €11,000–15,000 ex. VAT (ram + computer + sensors + Madintec + 20 h labor).
5 common choice mistakes seen in the workshop
Ram choice mistakes — seen at Skysat workshop
- Undersizing due to optimism. The boatbuilder lists 7.5 t displacement, so we choose Type 1. Except the boat sails with 800 L of water + fuel + crew + 200 kg gear = 9.5 t real displacement. The Type 1 struggles, overheats, and eventually fails. Always size based on actual sailing weight, not builder’s weight.
- 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 you’re hand-steering 18 h/day. The real savings are negative.
- Hydraulic without automatic bypass. If the hydraulic system lacks automatic bypass valves (common in older kits), the rudder remains locked even with the pilot off. The helmsman struggles, the crew complains. Always verify bypass presence at purchase.
- Choosing an incompatible brand with the existing ecosystem. The boat has a Raymarine Axiom chartplotter. The customer 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 interfaces with everything.
- Undersized hydraulic pump relative to the cylinder. A 15 kN cylinder with an undersized pump = slow correction, the autopilot lags, oscillations occur. 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 installation is heavy: new hydraulic cylinder, new pump, high-pressure hose runs, system bleeding, possible rudder quadrant modification. Allow 16–24 h labor + €2,500–4,000 material depending on configuration. Only relevant if the boat’s program changes 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 for its nominal voltage. The computer + rudder angle sensor + compass pairing can come from any ecosystem. Verify the L&S existing electrical interface (voltage, max current, position feedback type) and adapt the computer accordingly. The Madintec MAD Controller is designed to drive almost any ram on the market.
What’s the difference between reversible and non-reversible hydraulic?
Reversible = double-acting pump (can push or pull the cylinder), requires bypass valves to free the rudder. Non-reversible = single-acting pump, the rudder is mechanically linked to the pump-cylinder when the pilot 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 in 99% of cases. The pump is mounted in a ventilated technical locker near the cylinder. Wet pump (immersed in the oil reservoir) exists in some older systems but requires a sealed reservoir and full disassembly for maintenance. If refitting, switch to a modern dry pump.
Rudder ram vs. tiller quadrant — compatible?
Yes in almost all pleasure boat configurations. The ram drives the tiller quadrant (the part that transmits rudder rotation to the rudder blade) via a connecting rod. Compatibility depends on the quadrant’s rotation angle (typically 70° total, ±35° each side), the ram’s stroke, and available space. Always verify with an on-site workshop measurement before purchase.
Should we plan a backup ram for offshore?
Not a backup ram, but a backup strategy: emergency tiller / windvane (Aries, Hydrovane, Windpilot) for sail, or a kicker / removable tiller for power. The electric ram is a sensitive system — for a transatlantic, plan at least a manual rudder return cable with the ability to disconnect the ram-quandrant coupling (typical removable pin). See our ram maintenance guide for warning signs of failure.
What wiring should be used between computer and ram?
Wire gauge calculated on max ram current + 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): 2 × 6 mm² minimum, up to 2 × 10 mm² for high-power 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. This article reflects our experience installing autopilots on over 120 sailboats between 2018 and 2026, in cruising and offshore racing. 2026 ex. VAT prices are indicative distributor prices, excluding specific wiring and mechanical adaptations to the existing tiller quadrant.
