Narrowboat propulsion actual power ?

[Boo2]

Hi,

Question as title: how much actual power at the prop would a 60' narrowboat require to travel along a canal ? I see that many are out there with engines rated at ~35hp, but how much is actually used to move the boat along ? Anyone know ? Alternatively, what rpm / throttle percentage do you use on your narrowboat when just driving along, rather than manouvering or starting off etc ?

Thanks,

Boo2

 

[Daydream believer]

Years ago a yachting magazine published a piece about a Seagull century pushing a very long barge along a canal. The max of a Century is 5 HP
One has to consider that lots more will not push the vessel faster. The water has to pass between hull & canal bottom & the stern will just dig in if the water is removed & not replaced in time.
Does that reasoning fall in line with canal boaters?

 

[oldbloke]

Traditionally just one horse was considered sufficient (sorry).
More seriously , I suspect the extra power is used for acceleration, deceleration and manoeuvring. You would also need more if you venture onto any of the rivers

 

[Gumpy]

50hp Beta in my old NB
4mph at 1200rpm
5mph at 1450rpm
7.5mph at 1800rpm
All speeds from the GPS speedometer and in deep water (River Nene). Speedometer fitted as I got warned for speeding twice on the Thames just after I got the boat.
In reality less than 10hp would be enough to move the boat but having extra power gives one a nice edge.
As for the canals I used to sit at 1000rpm unless it was a known deep stretch.

 

[scottie]

Traditionally just one horse was considered sufficient (sorry).
More seriously , I suspect the extra power is used for acceleration, deceleration and manoeuvring. You would also need more if you venture onto any of the rivers

Neigh chance where to keep the hay and the fumes and etc are rather ant social but it does explain the origins of towpath if desperate you could look up legging

 

[Tranona]

Theoretical hull speed for 60' is around 10 knots so the normal cruising speed of 3-4 knots is likely to be between 10-15hp or under 2000rpm for a 35hp engine with a maximum rpm of between 3200-3600.

 

[srm]

I had a day out on a friend of a friend's narrow boat (around 45ft) on the upper reaches of the Thames one Christmas eve. Engine the same as I had in a previous 29ft yacht, a single cylinder Sabb 8HP. Chugged along quite nicely at around half throttle and more than enough power to manoeuvre.

 

[[194497]]

I had a 57' narrow boat with a 40hp engine and I barely had it above tickover speed for canal cruising. Even manoeuvres on the river in slightly too much current didn't require anything like full power.

 

[billskip]

It's nice to have extra hp for stopping, the prop is very inefficient in reverse.