High-Speed Propulsion Engines
Compact engines running above roughly 1 000 rpm for patrol craft, pilot boats, crew transfer vessels and small ferries, where weight and engine room space are limited.
Features
- Power for their mass and footprint is high, so the binding limits on an installation are usually exhaust back pressure and engine room air supply rather than the bed, and both are checked against the engine's stated maxima.
- Usually turbocharged and charge-air cooled, so charge air cooler condition has a direct effect on available power and exhaust temperature.
- Service intervals are shorter than on a medium-speed engine, and the maintenance plan has to reflect the hours the vessel actually runs.
- Suited to intermittent and variable-load duty rather than to continuous full-load work.
- Instrumentation and control heads are specified with the engine, since retro-fitting a different control system afterwards is rarely economical.
Specifications
| Figure | Typical range | Unit | Why it matters |
|---|---|---|---|
| Rated power and speed | 294 at 2 300 | kW at rpm | the pair of figures that define the rating |
| Duty rating | medium duty, 3 000 h per year | a warranty condition, not a recommendation | |
| Dry mass | 980 | kg | affects trim and the bed design |
| Charge air cooling | seawater / freshwater intercooled | cooler fouling shows up directly as lost power |