donald_of_tokyo wrote:Thanks Shark-bait-san!! Great info!!shark bait wrote:An interesting slide from a Damen presentation comparing length vs costs, important to not this is for patrol vessels not necessarily frigates.
They suggest increasing the platform size by 50% only increases build costs by 6%, whilst yielding efficiency saving in other areas.
I think this
http://www.hiswasymposium.com/assets/fi ... m-2006.pdf
is better for read.
The numbers quoted is for fast boat, 26m long. The important assumption is as follows:
The Enlarged Ship Concept
In 1995, Delft University and Damen Shipyards carried out a desk study on the influence of hull lengthening on the “practical characteristics” of a ship. In this study, a 26 m Damen Patrol Boat was taken as the “parent ship”. In two steps the hull of this design was lengthened respectively by 25% and 50%, See Figure 1. Similar studies were carried out before, but in this case it was decided to keep the functionality of the two lengthened versions completely equal to the original design. In other words, only the hull length was varied, the accommodation, superstructure, speed and range were all untouched. For the three designs, the following “practical characteristics” were determined:
• Building cost
• Operational cost (i.e. mainly fuel)
• Transport efficiency
• Operability (i.e. sea-keeping characteristics)
The production result was the Damen 4207 patrol boats, the ones you have in your Border Force. When looking at it, I was surprised by its sleek hull, low height, and lightweight (~250t) compared to its length. (The RNZN Protector-class inshore patrol vessel has similar length, but weighs 340t). I liked it a lot. Simple, smart, efficient.
The "Enlarged Ship Concept" answers everything. Great.
Note that, they "keep the functionality of the two lengthened versions completely equal to the original design. In other words, only the hull length was varied, the accommodation, superstructure, speed and range were all untouched." So this enlarging hull has NOTHING to do with adding any assets, not mission bay, not accommodation, no additional armaments.
Comparing the results of the three variants, some very interesting conclusions were drawn for the lengthened designs:
• Building costs are only influenced marginally by the hull length, due to the fact that the extra length is “empty”.
• Operational costs decrease, due to lower resistance
• Transport Efficiency increases significantly
• Operability increases significantly
Also note they say " In the study, the hulls were lengthened by simply increasing frame spacing. "
So I think this is not for adding any assets. JUST making your ship LONGER.
A UK Border Force cutter will stop in Gibraltar today on its way to the Aegean Sea as part of a Nato deployment to tackle people smugglers.
HMC Protector will stop in the Naval Base to pick up fuel and stores before sailing east into the Mediterranean.
The vessel is part of a wider deployment announced by the British Government yesterday.
PAUL MARSAY wrote:how many border force cutters have we ? are they now mainly in the med ?
marktigger wrote:they should look at a 2nd batch of these cutters for the UKBA and also batches for the RN and RNR
marktigger wrote:That then generates the issue of deploying the OPVs in lieu of a frigate.
shark bait wrote:Rivers a too big for the border force. The better option would be to sell them and invest the proceeds into some new Damen patrol boats.
shark bait wrote:Protecting rockall shouldn't be a priority so that cuts out a big chunk.
Scotland has their own arrangements, and the big threat is not from smugglers but submarines, to which a river would be useless.
Really it is the Irish sea, the north sea and channel that would require the intensive patrols, where the Damen vessels will do just fine.
Or we could copy the Australians; https://en.wikipedia.org/wiki/ACV_Ocean_Protector#
I see little reason to keep those rivers. The choice would be something like 3 rivers, or 6 cutters. I would vote for the 6 cutter choice.