Understanding influence of underwater shape on reversing
- Thread starter NigelCraig
- Start date
boguing
Well-Known Member
I was talking about reversing into a berth. Get it steering upwind and then reverse to the berth, which can be in any direction.
Reversing out though, you must know which way the prop will walk. First aim is to get the boat out and stopped with the bow down downwind. If the bow is downwind in the berth then just use reverse idle and let the wind push you out, while the boat is 'hanging' from the prop
More later when I'm on a real keyboard.
Reversing out though, you must know which way the prop will walk. First aim is to get the boat out and stopped with the bow down downwind. If the bow is downwind in the berth then just use reverse idle and let the wind push you out, while the boat is 'hanging' from the prop
More later when I'm on a real keyboard.
V1701
Well-Known Member
The Vega is not good in reverse mainly because the prop is behind the rudder, so the prop's position in relation to the rudder is a factor. A neighbour had a Rival 32 (I think exactly the same as 34) & he did alright getting out in reverse but not as manoeuvrable as a modern fin keeler. Also with long keelers the prop aperture is a factor, e.g. from Yachtsnet Archive page "Unusually for a long-keeled boat, the Vancouver 32 can be steered astern quite effectively, probably due to the large prop aperture separating keel and rudder." Page link:
http://www.yachtsnet.co.uk/archives/vancouver-32/vancouver-32.htm
http://www.yachtsnet.co.uk/archives/vancouver-32/vancouver-32.htm
Blueboatman
Well-Known Member
I like TwisterKens old anecdotal suggestion that if you can get a long keeler going fast enough backwards then eventually it will start to go in a straight line..
I have yet to achieve the required velocity ( not speed, velocity eh) in a restricted waterway...
I have yet to achieve the required velocity ( not speed, velocity eh) in a restricted waterway...
jwilson
Well-Known Member
Have also found both Rival 34 and Contessa 32 to be not too bad for control under astern, though I try and use a burst of power to get moving then go to neutral or tickover. On my previous long-keeler, similar to a Cutlass but bigger, there was no unpredictability whatsoever astern: the stern would turn to port whatever you did with the rudder.
johnalison
Well-Known Member
Understanding influence of underwater shape on reversing !
You clearly have not appreciated the relevance of my reply.
In many situations, boats with long keels will not aim to steer while going astern (be patient) but will manoeuvre their boat with alternating bursts of ahead and astern, using the kick of the rudder when in ahead to correct the boat's heading. This option is not available to owners of boats such as the Nick 32, for similar reasons to the difficulties people have with twin rudders. I hope I have made myself a little clearer.
jwilson
Well-Known Member
The Nic 32 is a pretty standard long-keeler, prop in cutaway between keel and rudder, so you can get some deflected propwash from the rudder blade to kick you round a bit. Some early Nic 35s though had the prop at the aft end of the fin keel, a long way from the skeg/rudder. Albin Vegas even worse - the prop is BEHIND the rudder blade.
johnalison
Well-Known Member
Dear Namesake. You are trying to demolish my Nic friend's contention that his boat does not obey the laws of physics. He won't be pleased.
Leighb
Well-Known Member
I like the statement in a review of the Halmatic 30 concerning the handling under power.
"Like most long keeled yachts, she is predictable in her unpredictability."
That says it all in my experience. We don't formulate a Plan when reversing out of a berth, we have a vague aspiration and then adapt to whatever she throws at us. We have learnt that in certain states of wind and tide it is better not start at all.
"Like most long keeled yachts, she is predictable in her unpredictability."
That says it all in my experience. We don't formulate a Plan when reversing out of a berth, we have a vague aspiration and then adapt to whatever she throws at us. We have learnt that in certain states of wind and tide it is better not start at all.