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[unbuiltnautilus]

Hi Yarpie,
We have put our best scientific minds on this problem, if it sinks to the bottom of the test tank when pumped down, its got too much water in it. Therefore, next time, we will use less water.
See, scientific

[triumphjon]

have you fitted any bouyancy , just in case ?

[unbuiltnautilus]

The plan is to test the model with both ends, bow and stern buttoned up and watertight, in our 9' test tank ( TWO baths glued together, dont do nothing by halves down here in Portsmouth! ). We slowly fill the model up , if there isn't enough bouyancy on board, we will fit foam blocks into the centre section as needed. Rather like ballasting a model submarine. The foam blocks can be used to trim the model to port or starboard slightly, as well as altering fore and aft trim as needed. Once we are satisfied with the trim of the model flooded, the blocks can be permanently bonded into position.
Well, thats the plan....

[triumphjon]

i have some 2" foil coated stuff in the shed should you need some ?

[unbuiltnautilus]

Cheers Triumphjon,
Thanks for the offer, however at last years Southern model Airshow at Hop Farm I picked up some blocks of EPP Foam, ( looks like expanded polystyrene, but doesn't crumble into bits like expanded polystrene. ) enough for about four submarines and one tanker!!

[farrow]

Hi Allen,
Found this photo on the net, I expect you probaly already have, in case you have not I have attached it. By the way have thought of another way to attach Destroyers without having to fit anything to them such as pegs etc, when I am in your shop next with Bob, I will put them to you.

[Yarpie]

Old Dodes,

nice image of the OHIO being shepherded into Grand Harbour.

Would you consider sharing your idea of tethering the two destroyers with us online?  I'm interested insofar as the two ideas stumbling around what remains of my brain are getting somewhat lonely!   (They are: 1. using the idea of outriggers to trap a projection under the destroyers keels, and: 2. some sort of electro-magnetic means [which can only be tested once the ships side is fitted to OHIO]).

Both of these options have been discussed earlier in the thread, but it is both refreshing and encouraging to hear that somebody else is interested and committed to the cause.

Happy New Year to you.

Yarpie.

[farrow]

I was thinking of a U shaped bracket in the vertical plain to fit abreast of the destroyers forescastle brake attached to the tanker and on the horizontal plain another bracket for the destroyers stem to lean on. This way the destroyers do not have to be modified in any way and with the vertical bracket that far back on the destroyer, the destroyer would be held fairly firm. The brackets can be manually adjusted to give best fit. Also the tanker would be very deep in the water when fully loaded anyway as tankers have a lot smaller freeboard to a normal freighter as they do not have cargo hatches to worry about, so she should not go much deeper through damage to the hull, also water will only go to the height of the hole after that the oil stays and gives some flotation. As I say it is only an idea, I expect knowing Alan he has researched it all out and has his answer to all the problems. Myself I am looking forward to seeing his display, as the Pompey boys have a reputation for giving very good displays.

[triumphjon]

my only concern for having boats attached physically would be what would happen should thte tanker start to sink too far , does it then take the other two vessels down with it ? maybe  the " support vessels could have a radio operated shoot bolt to locate into an open topped slot in the tankers sides , should the tanker sink too far the shoot bolt will be free !

[unbuiltnautilus]

I was thinking of a U shaped bracket in the vertical plain to fit abreast of the destroyers forescastle brake attached to the tanker and on the horizontal plain another bracket for the destroyers stem to lean on. This way the destroyers do not have to be modified in any way and with the vertical bracket that far back on the destroyer, the destroyer would be held fairly firm. The brackets can be manually adjusted to give best fit. Also the tanker would be very deep in the water when fully loaded anyway as tankers have a lot smaller freeboard to a normal freighter as they do not have cargo hatches to worry about, so she should not go much deeper through damage to the hull, also water will only go to the height of the hole after that the oil stays and gives some flotation. As I say it is only an idea, I expect knowing Alan he has researched it all out and has his answer to all the problems. Myself I am looking forward to seeing his display, as the Pompey boys have a reputation for giving very good displays.

Thanks for the input, the main issue with the design of this system is that the draught of the Ohio will alter through the display as water is pumped into the model following the simulated attacks on the fleet. The method used to secure the destroyers will have to involve something that, preferably remains invisible at both light load and deep draught. Contrary to popular belief, I dont yet have the answer to this one as it involves not just  the Ohio model but also, at least two of the teams destroyers. therefore , the request to drill holes through their models will need some discussion!! Now back to the new year celebrations, JD and lemonade tonight...

[triumphjon]

hence a shoot bolt in the side of destroyers to locate in a slot in the tanker hull , will explain , give diagram next time im in shop , aint worked out how to draw pics on these machines yet , ive not long learned how to type !

[unbuiltnautilus]

god bless, you sweet west country type!!!

[farrow]

Gents the Ohio was deep loaded with cargo, when she lost some to splinters, not alot she probaly only went down 3 ft or may have come up with cargo burnt off a few feet. I doubt if there was a major change in freeboard.

[Yarpie]

Great to see discussion on this topic.   Precisely what the site is about.

Hope your New Years Eve celebrations went well. (Nice bottle of Claret destroyed a further 20% of my brain cells).

Thanks for responding Old Dodes and your input is appreciated. (Especially by the destroyer boys no doubt!!).

[bat44]

the bolt idea is a good one but you need to be lined up in the right spot to fire the bolt, and to do this from a distance could be a bit of a problem at best.I believe a post in the bottom of the destroyers and a v shaped bracket on the tanker would be the best and simplest option to do,as then the two destroyers only have to come along side and keep going forward to they hit the v bracket on the tanker.  When the two boats are along side all they provide is forward momentum as the tanker doses the steering and braking

                                                    bat44

[John W E]

Hi ya

Have you thought about considering magnets to secure the two destroyers to the side of the tanker?   

When I used to work in some heavy engineering industries - around open pieces of machinery - there used to be steel safely cages.  The doors on these cages were always kept secure using strong horseshoe shaped magnets.  Knowing that megnets of this strength are available; I would suggest 3 of the magnets are placed both port & starboard on the insides of the tanker and corresponding steel plates are placed on the inside of the destroyers - as soon as the destroyers come alongside the tanker and the plates then line up with the magnets - you may have some difficulty removing the destroyers from the side of the tanker.   

Another thing if you use magnets of the suggested strength you better put a warning up for people who have pace makers fitted.   In fact the possibilities are endless you could end up with a tanker which collects all steel garbage from the bottom of the lake.  mmmm food for thought there my friend.

aye
john

[tigertiger]

That was my first thought, magnets.

[bat44]

just had an idea well bro's idea the best one in years for him , if the destroyer boys do not want to put holes in their boats how about gluing a tube to the bottom of their boats length ways,and then insert a bar bent at 90 degrease and secured in with a pin or a couple of bolts.This can also be used as a keel weight in bad wheather


                                                                                  bat44

[triumphjon]

i hear talk of electro magnets , possibly placed in the side skins of the tanker , with a corrisponding plate inside the destroyer hulls , which sounds much better than modifying the hulls of much prized destroyers , would also mean that by including a section of steel along each side of the escort ships then different models could be substituted should the need arise ?

[bat44]

magnets is a good idea but what sort of magnets and how strong will they need to be? and what if you can not put a metal plate in the boat,and would this not put extra weight into a boat that has a low free board


                                                       bat44

[bat44]

talking to one of the destroyer boys today he thinks that having a post from the bottom of the boat is the most easiest, simple and safest option. But if any one has a better idea  

                                 bat44

[Klunk]

nodym magnets are very strong and free if you crack open some old hard drives!!! find a pc repairer, they normally throw old hard drives!

[John W E]

This afternoon I looked onto RS Components website, to look for door magnets that we used to use at work - cos I know they are very strong - there are several magnets on the site which are equivalent to the safety magents which we used to use.   Also, I noticed there were elctro magents used for safety doors - the voltage on these varied from 24 volts to 230 volts.   24 volts I should imagine would be no problem with 2 x 12 volt batteries linked together.   Drawback though - price - bit heftily priced these electro magnets

aye john

 http://uk.rs-online.com/web/search/searchBrowseAction.html?method=retrieveTfg&binCount=59&Nty=1&Ntx=mode%2bmatchallpartial&Ntk=I18NAll&Ne=4294957561&Nr=AND%28avl%3auk%2csearchDiscon_uk%3aN%29&N=4294955519&Ntt=magnets

[Yarpie]

bat44, good input man.  As a destroyerman in reality (3 WWII destroyers during a 25 year RN career) and also as a model boat destroyer driver, I would go for the 'drop down post' method. The reason behind this is purely selfish. I own two of the half dozen or so destroyers that may be tethered to the side of a sinking OHIO.  I don't want to lose either. As in REAL SEAMANSHIP , when replenishing at sea (fuel or solids), or when two (or more) ships are connected by whatever means, a quick breakaway mechanism is ESSENTIAL. I had a friend die in the HMS FITTLETON disaster.

I have a highly qualified colleague looking into the possibilities of electro-magnetic connection but we have discovered a time lag when the magnets are de-activated. This could be between one to five seconds, so much work needs to be carried out in this field to ensure an instant breakaway, should it be necessary.

Another alternative suggested is the horizontal tube running along the keel method. There is definitely mileage in that too.

Thanks everybody for your input in this little conundrum. Perhaps it may have been better for our little display team if the actual OHIO had not been so stubborn and had relented and sank following the massive damage she received.   But therein lies the challenge.

[triumphjon]

re the electro magnets , at least its not quite so critical as to the location alongside , as a realativly large length of steel could be placed along the inside of the destroyers hulls , it would also pay to fit this along both inside faces thus making vessels universal to whichever side they were needed ? would fitting extra bouyancy in the destroyers help with peace of mind ? i see the offshore racing guys fit pool noodles inside there hulls !