The essentials 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, 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. Power, 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 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 power unit of the autopilot. It converts an electrical signal into rudder movement. Two technology families coexist: electromechanical (electric motor + worm screw) and hydraulic (pump + cylinder). Choosing one or the other determines 10 years of use, the refit budget, and the autopilot's relevance 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 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 screw 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, installed 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 travel 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 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 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 sailing, increase to 1 500 N/t.
- 8 t cruising sailboat → ram 8 kN minimum → Type 1 electromechanical or light hydraulic.
- 14 t offshore cruising sailboat → ram 14 kN → Type 3 electromechanical or T2 hydraulic.
- 20 t racing sailboat → ram 30 kN → large-travel hydraulic (DD15, MK3+).
2. Rudder speed (degrees per second)
The speed at which the ram can correct a heading deviation. Critical in rough seas and racing.
- Typical electromechanical: 3-6 s for full rudder swing (35° each side).
- Typical hydraulic: 2-4 s for full rudder swing.
- Typical hydraulic direct drive racing (Simrad DD15, Lewmar GP): 1-2 s for full rudder swing.
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 (logic power only).
- 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 generally equivalent between the two technologies — hydraulic consumes more at peak but cycles faster, so for less time.
4. Reversibility (barman ↔ autopilot ↔ barman)
The ram's ability to free the rudder when the autopilot is disengaged.
- Linear electromechanical: the worm screw mechanically locks the rudder even with the autopilot off. "Braking" sensation for the barman, who must push against the internal resistance of the ram. Major drawback in racing and short-handed sailing.
- Hydraulic with automatic bypass: autopilot off = open valves = rudder 100% free. The barman resumes without any resistance. This is the criterion that drives 90% of racing programs toward hydraulic.
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.
- 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 structural frame and rudder quadrant. Installation in 4-8 h workshop.
- Hydraulic: 2 elements (pump + cylinder) connected by high-pressure hoses. Installation 8-16 h workshop (hose runs + system bleeding).
- Hydraulic direct drive racing: complex integration on rudder shaft, installation 16-32 h.
Linear electromechanical ram — details and brands
The historic technology for sailboats 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 line. 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 order.
Lecomble & Schmitt MK1/MK2/MK3
Historic French manufacturer (Vendée). Very common on new Bénéteau/Jeanneau sailboats. Rod travel 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.
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, full rudder swing 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 original hydraulic cylinders (e.g., Bénéteau Yacht line yachts).
Lecomble & Schmitt hydraulic MK1/MK2/MK3
Separate pumps and cylinders, hydraulic equivalents of the L&S electromechanical line. Widely used in French offshore racing (IMOCA, Class40). Available on special order via Skysat.
Comparison table by size and program
| Sailboat | Program | Recommended tech | Ram 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 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 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 | Hydraulic direct drive | Simrad DD15 (1 962 €) + NAC-3 + Madintec | 15-22 kN | 12 000-18 000 € |
| ≥ 20 m yacht | Yacht configured CZone | Hydraulic external pump + third-party cylinder | Garmin SmartPump v2 + Reactor 40 GHC 50 | 15-22 kN | 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 cruising 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 € VAT excluded (ram + 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 reversibility barman ↔ autopilot (rotating crew) 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 € VAT excluded (ram + computer + sensors + 12 h labor + oil).
55 ft sailboat (16.8 m) / 16 t — offshore racing + transatlantic with crew
- Recommended choice: hydraulic direct drive with premium racing computer (Madintec compatible).
- Skysat solution: Simrad DD15 (1 962 €) + NAC-3 (1 649 €) + sensors + Madintec MAD Controller (2 550 €) racing upgrade.
- Total installed budget: 11 000-15 000 € VAT excluded (ram + computer + sensors + Madintec + 20 h labor).
5 common mistakes when choosing a ram
Ram choice mistakes — observed in the Skysat workshop
- 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 water + fuel + crew + 200 kg gear = 9.5 t real displacement. The Type 1 labors, overheats, and eventually fails. Always size based on actual sailing weight, not manufacturer weight.
- Choosing electromechanical to "save" 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 drops out, and you're hand-steering 18 h/day. The real savings is negative.
- Hydraulic without automatic bypass. If the hydraulic system lacks automatic bypass valves (case of some old kits), the rudder remains locked even with the autopilot off. The barman struggles, the crew complains. Always verify the presence of bypass 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. Always match 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 modification of the rudder quadrant. Count 16-24 h workshop labor + 2 500-4 000 € material depending on configuration. Relevant only if the boat's program evolves significantly (cruising → racing, or offshore upgrade after insufficient coastal 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 combination can come from any ecosystem. Verify the ram's electrical interface (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 barman 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 boat configurations. The ram drives the rudder quadrant (the part that transmits the rudder rotation to the rudder) via a connecting rod. Compatibility depends on the quadrant's rotation angle (typically 70° total, ±35° each side), the ram's travel, and available space. Always verify with a workshop measurement on site before purchase.
Should a backup ram be planned 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, plan at least a manual rudder return cable with the ability to disconnect the ram from the quadrant (demountable pin typically). See our rudder ram maintenance guide for warning signs of failure.
What wiring should be planned between computer and ram?
Wire gauge calculated on the ram's max 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 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 of authorized distributor rates, excluding specific wiring and mechanical adaptation to the existing rudder quadrant.
