Propulsion options
Practical Boat Owner|Summer 2022
Inboard diesel engines are common for sailing cruisers, but there are other ways to power a boat, as Stu Davies explains
Stu Davies explains
Propulsion options

Rarely do we get to choose how our boats are powered. The usual scheme of things is we choose a boat on a myriad of parameters, of which one is the propulsion system. But having talked about diesel inboard engines and their replacement last month, perhaps a few words on other types of installation wouldn't go amiss.

Conventional power units for cruising yachts, and I use the word 'power' to encompass electric power as well, usually drive through a propeller shaft or a sail drive. Of these two, a conventional prop shaft drive is the simpler and cheaper to maintain. Saildrives have bellows and seals that require regular checking and replacement and are principally made of aluminum that's permanently under the waterline - requiring a degree of monitoring that a stainless steel propeller shaft with a bronze propeller on the end of it does not.

However there are other ways of putting that thrust into the water, especially when we consider vessels beyond cruising yachts, and these installations can be electrically powered too. They are namely:

  • Stern drive
  • Outboard
  • Jet drive

These forms of getting power into the water still use propellers but drive them through slightly different mechanisms. They're mainly fitted to power boats.

Stern drives

A stern drive is basically a sail drive but it is fitted to the transom of a boat with the engine hanging on the inside and the drive on the outside.

Denne historien er fra Summer 2022-utgaven av Practical Boat Owner.

Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.

Denne historien er fra Summer 2022-utgaven av Practical Boat Owner.

Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.

FLERE HISTORIER FRA PRACTICAL BOAT OWNERSe alt
Orca sink yacht in Strait of Gibraltar
Practical Boat Owner

Orca sink yacht in Strait of Gibraltar

Spain's maritime rescue service, Salvamento Maritimo, has reported that a 15m (49ft) yacht sank in Moroccan waters in the Strait of Gibraltar following interaction with a pod of orca.

time-read
1 min  |
Summer 2024
No kill cord or lifejackets were worn during fatal powerboat crash
Practical Boat Owner

No kill cord or lifejackets were worn during fatal powerboat crash

A kill cord and lifejacket are useless unless worn-that's the warning from the Marine Accident Investigation Branch (MAIB), following its investigation into a powerboat crash that killed a 32-year-old woman and five-year-old girl on 2 October 2022.

time-read
2 mins  |
Summer 2024
Multihull sail work
Practical Boat Owner

Multihull sail work

Brush up on multihull sailing skills before heading off on charter with Gavin Le Sueur's guide to spinnaker handling, tacking and gybing

time-read
4 mins  |
Summer 2024
Five top causes of engine failure and how to prevent them
Practical Boat Owner

Five top causes of engine failure and how to prevent them

Jake Kavanagh talks to Sea Start marine engineer Nick Eales about how to avoid the five major causes of an engine breakdown at sea

time-read
10+ mins  |
Summer 2024
Sail the Atlantic with strangers
Practical Boat Owner

Sail the Atlantic with strangers

Would you sail across the Atlantic with someone you've just met? Ali Wood meets the cruising crews who've done just that

time-read
10 mins  |
Summer 2024
IZIBoat: simple sailing
Practical Boat Owner

IZIBoat: simple sailing

Rupert Holmes sails an innovative catamaran design intended to widen participation in sailing among those with little time to get on the water in more conventional craft

time-read
7 mins  |
Summer 2024
30 WAYS TO GET AFLOAT
Practical Boat Owner

30 WAYS TO GET AFLOAT

From tall ships to small dinghies, you needn't own a boat to sail. Ali Wood looks at the options, and how skippers can also find crew

time-read
10+ mins  |
Summer 2024
Boats for restoring under £20,000
Practical Boat Owner

Boats for restoring under £20,000

Duncan Kent picks the best sub-35ft sail and power boats to look for when aiming to undertake a restoration on a budget

time-read
10+ mins  |
Summer 2024
Seaworthy dinghies for less than £500
Practical Boat Owner

Seaworthy dinghies for less than £500

For low cost traditionally-styled GRP trailer-sailers, consider the Foreland and the Otter available at bargain basement prices

time-read
5 mins  |
Summer 2024
Playing with coloured sails
Practical Boat Owner

Playing with coloured sails

Maintaining an hourglass-shaped balloon and ratcheting up the log numbers

time-read
3 mins  |
Summer 2024