Do Springers create less wash?

[PhilR]

These narrow locks have whirlpools.

 

 

 

This is the boat now.

 

 

Is that your boat in both images?

[leeco]

 

Is that your boat in both images?

Yes the 1st is what it looked like when we bought it and that last pic is what it looks like now.

[MaryP]

The heave of water (not the wash) is approximately proportional to the ratio between the cross section of your boat and that of the canal. So if you have a deep drafted flat bottomed boat with a cross section of say 1.5sq.m. passing along a canal of say 10sq.m. the ratio is 0.15. If you have a shallow vee bottom with a cross section of say 0.8sq.m. in the same canal the ratio is 0.08, approximately half. So there will be half as much water trying to rush past your boat. Of course the effort to drive the boat under such conditions (against the apparent current) will be less for a Springer, meaning less revs, less wake, etc.

Sounds good!

 

Of course, the V bottom means that when boats pass at any speed, pins pull out, so chains and piling are best...

[leeco]

A v bottom might not cause as much as a flat bottom but you still get boaters looking at how fast you are going thinking you are a boy racer telling you to slow down.

 

They don't even know what waves you have left behind but when they are shouting and telling you off all you can see on a springer is a mouth moving up and down.

 

I just wave at them lol.

[Theo]

 

The person that said a V shaped hull as used by Springers reduces roll has probably never compared a Springer with a conventional flat bottomed narrowboat on the average canal. Roll is reduced by using a V bottom, but only roll induced by wave action. Roll induced by moving about in the boat is increased. A boat with a deeper V or a round bottom rolls even more than a Springer on the canal.

But only if the non vertical part on the sides breaks the surface. If that doesn't happen then the righting moment for a given angle of heel will be the same as for a flat bottomed boat.

[p6rob]

My boat may or may not be a Springer. It has definite Springer and some very un-Springer like features. I've noticed that, despite travelling slowly passed moored boats, it can knock some around quite a bit. I've also noticed how the draw affects bankside reeds and grasses from a surprising distance.

 

I got passed by quite a few boats yesterday, including amongst other historics, Reginald (I waved through the window but you were resolutely not looking in) and despite the slow speeds and tight lines, they rocked my world quite a lot. I'm not sure if that's a feature of the V hull, the boat doesn't feel tender to me.

 

Rob

[Athy]

My boat may or may not be a Springer.

Judging by your small avatar picture, it isn't - unless, like some Springers, it has had its superstructure replaced. In particular, the shape of the rear sides is not Springoid at all.

[John V]

SPRINGOID........has a nice ring,,,I like it

[Athy]

Ta, Guv. Not entirely original, as engines with Lister-like features have been known as Listeroids for some time.

[Gazboatman]

 

Is that your boat in both images?

I can confirm, it is.

[Naughty Cal]

Speed past moored boats is directly related to the sound of the engine. At 1000rpm Loddon does about 2.8mph

that's as far as I go for slowing down, tickover is a lumpy 900. So far this trip only had cheery waves and hellos the only person that has complained is a fisherman, well I did pass at 3.9mph! If the engine was doing 1300rpm to achieve 2.9mph we would have got a lot of abuse

I believe some people actually believe this!

 

We have often passed moored boats at our tickover which is 600-700rpm at about 3mph to get cheery waves and hellos. Narrowboats or slower cruisers following us at the same pace have then been shouted at to slow down.

 

The only reasoning I can think of is that they have heard our engine revs slow but not those of the boats following.