howardang

Sad but predictable to see the discussion degenerate into the usual "playground" sniping. Why, for once, can't you respect each others opinions without this slightly puerile attitude! Regartds Howard Anguish

I think you'll find that that is exactly what I said in my first reply. Howard Anguish

Hi Tony, I think I remember the article you mention. There are two ways to fit a Kort Nozzle. The sinplest is to have a fixed nozzle around a conventional propeller. This is particularly beneficial for increasing thrust and therefore is the type that is fitted, for example, in tugs to give a greater bollard pull. It has the downside of reducing transverse thrust (prop walk) and needs a conventional rudder to be fitted directly behind the nozzle. The second is a steerable kort nozzle, which is a nozzle and propeller unit conbined which eliminates the need for an searate rudder but means that the transmission from the engine to the propeller is more complicated. This type is very good for steering and is sometimes fitted to ships lifeboats which is what I think Dave was referring to in his posting. Howard Anguish

Dave, unfortunately fitting a Kort nozzle wouldn't stop anyone getting sucked into the prop. One of the many reasons why they are not fitted to narrowboats in such shallow water conditions as canals is that they are more likely to attract debris and if large enough - such as bits of timber or other solid objects - they can, and do, jam up solid. The same thing could happen to a person who has fallen into the wter. Howard Anguish

David, Sorry to be a long time answering you but I have been away boating. I think we are talking at cross purposes. You mentioned that when taking your boat masters certificate you had been taught how to steer without a rudder and I would agree that it is possible to use transverse thrust in that way to a very limited effect, however, I would suggest that it is quicker and easier in a canal situation to use a pole to reach the safety of a bank. I have no argument about the use of transverse thrust as a part of boat handling and am grateful for your brief description of how it works. It is certainly not a party trick when used in combination with the rudder and it should be something that everyone handling a boat should be able to use to their advantage. I am fairly familiar with its effects having used it as a shipmaster quite effectively on ships both large and small for many years. Regards Howard Anguish

If you want to be technically correct the formal description of paddle wheel effect, prop walk or prop effect is actually Transverse Thrust. I would disagree that the shaft has to be at an angle - this effect is present with all propellers to a greater or lesser extent. Regards Howard Anguish

John, To try to clarify it for you:- Displacement is the weight of water displaced by a vessel - i.e. its weight at that particular draft. So if it is completely empty (no passengers, cargo, fuel water and stores) this is called the light displacement. When fully loaded with as much as it can carry the displacement is called the load displacement. The difference i.e. the amount of weight carried is the deadweight at any particular draft up to the maximum loaded draft allowed (shown by the load line marks or Plimsol line on the side of the vessel.) A vessel can be loaded to different drafts depending on season and/or where it will be going hence the different lines on a loadline, and because dockwater is usually less salty than seawater (hence less buoyant) a ships can load slightly deeper to allow for the fact that it will be proceeding into more buoyant water. Gross tonnage is a measure of the total volume of a vessel in cubic feet, divided by 100 (100 cu ft = 1 gross ton) or an equivalent in metric (volume inb cu metres divided by 2.83). This is an artificial tonnage which is used mainly for charging purposes ( dock dues etc) and sometimes charges are calculated using net tonnage which is the gross tomnnage less certain volume which is allowed to be deducted for crew spaces, machinery and navigation spaces etc. I hope that makes it a little clearer. Regards Howard Anguish

It does seem a rather pointless exercise - if you had lost your rudder the best place to be is on the bank, and if you hadn't lost your rudder then why not use it. It certainly wouldn't be practical to try and proceed for any distance by trying to steer using transverse thrust alone and I am surprised that David had to learn it for his BM exam. It might make a nice party trick given a boat with specific handling characteristics but no more than that! Regards Howard Anguish

Board of Trade certificate, David. Blimey, you must be a very old sea dog. The Board of Trade stopped issuing certificates many years ago Since then the Ministry of Transport, The Department of Transport both issued them before the present set up where they are issued by or on behalf of the MCA (Maritime & Coastguard Agency). Regards Howard Anguish

David, I wouldn't get too miffed about the difference in standard and training betwen a BM and the RYA Inland Helmsmans certificate. As you know, the latter is primarily concentrating on elementary boat handling where the former is a much broader based certificate aimed at a much higher level with the primary aim of protecting the public on passenger vessels on the inland waterways. I think your satisfaction in obtaing the BM certificate should remain undiminished! Regards Howard Anguish

If it's of any help, I have just retired after working as a dockmaster in Hull, a large port with a number of very large sea locks, docks, fast flowing river etc. In Hull there is a company on permanent contract, on call to remove any floating items such as bits of timber, old pallets etc. They have a number of workboats and tackle anything which might constitute a hazard to either shipping or to the dock infrastructure using cranebarges if necessary. In that context a relatively modest peice of tree trunk can jam under lock gates and cause extensive and expensive damage. This is also why tyre fenders are prohibited in Hull - if they fall into the dock they inevitably get trapped under dock gate cills. A regular clean up around the dock helps to keep the debris levels down to an acceptable level. Ships can also get floating objects wedged between the propeller and the rudder - especially ships fitted with nozzles - and this can be difficult to remove either by divers or even causing an unscheduled trip to drydock. This is particularly relevant for ships on the river berths. The Humber at times has a large amount of natural floating debris such as trees and bushes, washed away from river banks, together with the occaisional old timber from derelict jetties brought down river by the ebb current which can get up to 8/9 mph at times. As far as the MSC is concerned I would be very surprised if they didn't have a similar arrangement in place - either by contractor or by in house staff/vessels. REgards Howard Anguish

Yes, the SBNF became the British Marine Industries federation in the 90's which in turn has morphed into the Mrisitsh Marine Federation. It is still a trade federation but includes many other branches of the (mainly) leisure marine industry than boat building through various associated organisations such as THYA ( the Yacht Harbours Association), APCo ( Association of Pleasure Craft Operators), CBA (Canal Boatbuiders Association) and many others. HTH Howard Anguish

Gaggle, I hate to disagree with White Bear but depending upon where you are intending to anchor in the Mersey, both the weight of the anchor and the length of your anchor line are, in my opinion, inadequate. As a rough guide for a 56 ft boat you should be looking at at least a 20kg anchor - the heavier the better as long as you can physically handle it. The rule of thumb for rope is at least 6 times the water depth and you may need more depending on conditions. With an all chain anchor cable you need a minimum of 4 times the water depth. Again, you may need more. I have no direct experience of the Force anchor design so wouldn't like to comment. One thing which I would suggest is that you think carefully about how you will deploy the anchor and cable. The weights that can be experienced can be significant and can cause injury to the unwary. Also you need to consider how you will secure the anchor cable and finally how you will recover it. I would strongly recommend a practise in calm sheltered water conditions. HTH Howard Anguish

Try the lsitings of brokerage firms on http://www.ukcanals.net/brokers.html HTH Howard Anguish

Just a small point but Pan Pan Medico calls were abolished a few years ago. Howard Anguish

You aren't breaking the law, you are breaking the law and the fines can be quite substantial. The authorities carry out more checks than you may think. Howard Anguish

I agree that the Baby on board signs are sillyand more often than not there is no baby on board which will give the emergency services a run around in case of an accident. The silliest one I have seen so far is "Caution - Show Dogs in Transit." What on earth are we supposed to do when we see that? Howard

Snibble, nearly right - the Blue ensign is flown by those who have a warrant to fly it such as retired RN officers over a certain rank, members of the RNR certain yacht clubs with a similar warrant but NOT the Royal Yacht Squadron who have the right to fly the White Ensign which is normally only flown by British warships. I find it sad that so many people these days have no idea what the Red Ensign looks like or what it stands for but it possibly a reflection of the lack of concern for our national standards which has led to most of the shipping which services our needs these days coming from abroad rather than in British Ships. It was highlighted in the Falklands conflict when we struggled to find enough British merchant ships to support the task force and if we had to something similar these we just don't have the ships flying the Red Ensign to do it. Sorry - rant over. Howard Anguish.

Look on the British Marine federation web site WWW.britishmarine.co.uk go to Our Publications then legal services and you will find Sale of a Stock boat which might help. Good luck. Regards Howard

Yes Tony the captains hat is prattish but I think that flying a skull and crossbones is the ultimate in prattishness. What on earth makes people want to do that? Regards Howard

Well said, Chris, from another Grumpy old man. I hate to see flags being used incorrectly. Those very people who claim to be patriotic are sometimes the worst offenders. If you must wear a flag please fly the Red Ensign with pride. Howard Anguish

Hi Salty Seadog, Azimuth thrusters have limited use on canal boats because the shallow depth of the canals. The pods would be too deep and therefore the boat would be aground! A better bet would be a gill jet BT which would also give very good manouverability in all directions and yet would fit flush with the bottom of the hull. Regards Howard Anguish

AS a pedantic point you are, of course, quite right. Each "rope" has a purpose and therefore it's own name (even though it is made of rope). However I think the object of this mini-thread was to try to clarify what some mooring ropes are used for, not to confuse people further. In passing Alan Fincher is quite correct when he points out that I missed out the word "stern" line (or rope). This was a slip of the keyboard! Regards Howard Anguish

Hi again Alan, Just to slightly correct you if I may ..."at the stern a sternline" Howard