Nauticus Hull
Gabriel Litke
Nauticus Hull is our software package for strength assessment of hull structures. It offers all the tools you need for efficient hull design and verification according to DNV Rules and IACS Common Structural Rules for bulk carriers and oil tankers (CSR BC & OT).
During ship design and strength assessment it's essential to have the most effective tools that enable you to optimize the design process, the hull structure and ensure compliance with Class Rules. With Nauticus Hull you have access to a complete and integrated software package for all of the steps in the process.
Nauticus Hull is DNV GL's software package for strength assessment of hull structures. It offers all the tools you need for efficient hull design and verification according to DNV GL Rules and IACS Common Structural Rules for bulk carriers and oil tankers (CSR BC & OT).
When driving on a clear, open section of canal, operating the boat is nothing short of stressful. She will bounce left, right, left, right and all the while the helmsman can do little more than counteract this at the wheel, in turn the entire journey is spent corrective steering and if I'm to look away for a second, she's heading for the towpath. On the contrary, a few friends and I took her out last week whilst in a rather cold spell! - A complete sheet of ice had covered the waterway. The 1/4" of ice however was enough to keep the boat in a straight line and stable for the entire 8 mile journey and for the first time in years, it was actually a pleasure to navigate the boat.
My question is this. Why on earth does the boat handle like a shopping trolley? I have heard conflicting rumours about where to ballast the boat to try and aid this but I'd like to know a little bit more about it. I've put some old concrete blocks under the hull at the front of the boat and it seems to make little to no difference, but with friends sat at the front it's certainly easier to drive.
Outdrives are twitchy with the steering at slow speeds. You just have to compensate and try and second guess its next move. We had a similar problem when we bought our Sealine but have got the hang of it now. It does unfortunately mean a lot of steering. Take a look at any boat on the move with outdrives and 9 times out of 10 they will take a wander along the river/canal rather than steering a straight course.
I may of course be completely wrong (no change there), but is it a good idea to take a GRP boat out when the canal is frozen over? I know that some GRP hulls are stronger than others, but GRP cannot possibly have the same abrasion resistance as mild steel, and I would have thiought that persistant cutting through Ice could cause serious damage to the hull.
I only say this because back in the late 1960's, I witnessed a GRP boat being sliced in half by ice sheets pushed against her hull by a passing Working boat. The GRP sank in about ten seconds, it was quiter spectacular, even if somewhat distressing for the owner, who was fortunately not on the boat at the time.
You are very right on that matter. It is very bad practice to force a GRP hull through ice. Not only will you shread your own hull but that of any other GRP boat in the vicinity as you push ice against their hull.
Thanks for the replys! The ice was very thin and the hull is spotless afterwards so no worries on that avenue. Gel-coat is unscathed and we didn't pass any other boats owing to our mooring and where we were heading.
I have fitted a Bob Knowles aluminium extension piece onto the Z Drive last time it was serviced to no major avail - the boat responds infinitely better when under throttle which is obviously because it steers hydro-dynamically but otherwise at slow speeds, it is just uncontrollable - which is what is making me think it could be a ballast problem?
Funny you should say that, I was about to suggest ballasting the stern down. However I know to optimum fore-aft trim varies from design to design so in may be worth getting a few bags of sand/ballast from B&Q and try various fore-aft trims to see if it can be improved.
I have no idea about any keel the boat may (or may not) have, but fitting a long wooden keel gradually tapering from nothing towards the front to perhaps 4 or 6 inches at the stern may help. Unfortunately this probably means drilling right through the hull, screwing or bolting the keel on, and then glassing over the bolt/screw heads. Bit expensive though.
Oh dear, Buy a Viking instead!! Seriously, the problem is the hull flat bottom. I was once using a flat bottom boat in the Atlantic Ocean and that was all over the place, it was actually a glass bottomed boat used for diving. The only real cure for this is to fit a centre board in front of the half way point. You could also build a chine to the centre of the boat running fore and aft.