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High Speed Squirter Craft

Posted: Sun Jun 25, 2017 5:11 am
by Merlyn
Nice new picture of a headland spit somewhere on the opening screen, but where?
Also what about all this water being squirted to atmosphere out the back end of the ferry type jobby?

Or is it all fire hydrants exhausting to atmosphere knowing of Martin's return from his latest adventure based on that well known saying " every trips an Adventure "
Bit like welcoming large cruise ships and the like.
Wonder what it's like to be famous.

Re: High Speed Squirter Craft

Posted: Sun Jun 25, 2017 10:08 am
by D Winsor
Here are some more images of passenger ferries with the Rooster Tail water spray highlighted in the banner. The ferries run between the mainland, Mackinaw Island and Round Island on the Western Lake Huron side of the Strait of Mackinaw

Re: High Speed Squirter Craft

Posted: Sun Jun 25, 2017 7:29 pm
by The Dieselduck
Famous, who's famous.

Yes, I wondered as well, what the deal is with the massive rooster tail, seems like an awful waste of energy, but then again it is in Michigan. It was a beautiful spot, and had many of these crafts plying about, I had never seen them before. I think its mostly about marketing.

Re: High Speed Squirter Craft

Posted: Mon Jun 26, 2017 4:10 am
by JK
Water jet drives

Re: High Speed Squirter Craft

Posted: Mon Jun 26, 2017 6:05 am
by Merlyn
What, into the air? Back pressure from low flying clouds maybe?
Whose impeller kit over there?

Re: High Speed Squirter Craft

Posted: Tue Jun 27, 2017 6:01 am
by JK
No idea of make, I just googled the company. Maybe its a form of cooling the passengers by misting!

Re: High Speed Squirter Craft

Posted: Tue Jun 27, 2017 10:06 am
by Merlyn
Be better at nightime if strobe lighting were encased in the tail.
Just cant figure it all out looking at Dave's photos got to be an energy loss somewhere, maybe 2/3 knots on top rpm?
Havent seen a tail like that over here only a bleed off/ water pump indicator flow jet.
The smaller jet ribs are a pig when going astern I have found versus on shafts jobbies.

Re: High Speed Squirter Craft

Posted: Thu Jun 29, 2017 8:18 pm
by JollyJack
Roostertail is just wasted energy. I was quite amazed at the Halifax Class frigates, no roostertail at 30-odd knots, no quarterdeck vibration, just a smooth acceleration. You could stand a loonie on it's edge on the messroom table and it never moved. All the energy, 37 MW, goes into propulsion!

Re: High Speed Squirter Craft

Posted: Tue Jul 04, 2017 1:55 am
by Merlyn
JJ's remarks concerning those Halifax warships got me thinking about those proven LM2500 series, especially the mark 4 modifications with the extra compressor bladings fitted to increase the output.CODOG setups here.
You should be over here with our latest cockup Jobbies, the six in total type 45 warships.
Those gas turbines ( RR again) actually go on open circuit in hot sea temps and actually stop completely immobilised in the water.
You had one towed into Canada for emergency repairs back along.
Most of them have been laid up over here awaiting cutting out the ships sides in order to fit additional gensets in an attempt to get over the problem.
Billion pounds each goes the boast was the original cost plus all this rectification costings.
Bit like those duffer subs our lot sold to you over there.
Personally I reckon that was the purpose of JK's secret visit to U.K. recently, to put in a bid for them as it kept so many folk in work over there that now the subs lives was coming to an end they had developed an appetite for attempting to sort out OP's ( other people's ) cock ups and these type 45's certainly would live up to that Spec.
Project Napier they call it here.
Top secret mind.
The official explanation for the many months alongside?
The sailors need the rest and the night watchmen are on leave.
Doesn't look like RR are going to pay up so the British Taxpayer beware.
JK better be aware that any delivery trips have got to be via the pole as they won't run in higher sea temps.
Keep your folks busy for many a year.
However if JK bid over thirty bob apiece for them then JK's been ripped off.
After all, when alls said and done it's buying work, that's what the exercise is called.
They nearly fitted those LM 2500 turbines on shafts like you have in those Halifax classes, a well proven and tested bit of kit sadly unlike ours.
So any scraps with us over here will have to take place in low seawater temps. or it will be considered to be an unfair advantage under the terms of the Acts of War.
Unless of course JK's offer be accepted and you don't fit all these additional gensets to make er go and find yourselves in the Caribbean marooned forever sending picture postcards home entitled " wish you were here "
Don't forget in costing the water lines will have to be repainted and the even lower C_G means less cable to pay out when anchoring owing to the gensets additional weighing in factor.
I read that the RR gas turbines will be left for decoration purposes only as that's about their total achievement attained to date.
Such savings to be had.

Re: High Speed Squirter Craft

Posted: Thu Jul 06, 2017 9:53 pm
by JollyJack
I've worked with Ruston gas turbines in the North Sea rigs am LM 2500s in the Halifax class frigates, RR is considered to be the same junk as their diesel engines, great for selling spare parts!