A modern frigate?

[johnpjones1775]

The Constellations are not that expensive… basically a $600M hull with $300M of weapons & sensors. You could cut those of course, but that’s what brings all the capability (AEGIS, EASR, MK-41, CEC, COMINT, SQQ-89, SEWIP, NIXIE etc…).

LCS is a $450M hull with only $50M of weapons and sensors. It has no wartime utility without adding $$$ for modules and proper sensors and weapons, which it doesn’t have the SWaP-C margins to carry or the endurance to bring to the combat zone.

Notice that the difference in hull cost itself is only $150M. There are ways to build a cheaper general purpose frigate of course, but there’s going to be a capability trade-off and it will be hard to save more than $100-200M per hull while maintaining full spectrum AAW, ASW, ASuW, and EW capability… you’ll definitely lose AEGIS and some AAW capability along the way for example.

To save more than that (say if you want something for 1/2 or 1/3 the cost of an FFG-62), capability and hull-size would need to be drastically cut… see my ocean-going corvette proposal.

They’re $1.2b your numbers are falling $300m short

 

[Scott Kenny]

budget for building ships is probably an even bigger hurtle than the industrial capacity.

If congress won’t approve the funds to build these high end ships it doesn’t matter what our industrial base looks like.
If congress approves funding then ships get built, just slowly.

I’m all for getting smaller yards geared up and producing corvette-esque ships.

I think those will end up being XLUSVs rather than a baby Connie.

When a real naval conflict comes for us I think we’ll be happy we have LCSes, and after the conflict I think we’ll want to build more of them, and maybe even upgrade to MMSCs

That I doubt, their combining gears have been an issue since day 1. Maybe more LCS2s, the big helo deck is well liked.

They’re $1.2b your numbers are falling $300m short

$300m of weapons.

 

[johnpjones1775]

I think those will end up being XLUSVs rather than a baby Connie.



That I doubt, their combining gears have been an issue since day 1. Maybe more LCS2s, the big helo deck is well liked.



$300m of weapons.

No the freedom’s combining gears weren’t an issue from day one. The first 2 had 0 combining gear issues. I believe it was someone in congress that demanded the freedoms utilize a different cheaper combining gear in order to penny pinch.

Cost of missiles and gun ammunition isn’t part of the cost to build a ship.
Building them is 1.2b

 

[SSgtC]

They’re $1.2b your numbers are falling $300m short

That's just for the first couple ships in the class. Which are always more expensive as the kinks of building them are worked out. The costs are expected to drop below 1 billion after the first few hulls

 

[H_K]

They’re $1.2b your numbers are falling $300m short

I’m quoting official SCN budget materials so have 100% confidence in my numbers.

https://www.secnav.navy.mil/fmc/fmb/Documents/24pres/SCN_Book.pdf

It’s always a good idea to read the detail rather than take media reported numbers at face value… for example in this case the $1.2B quoted in news reports includes one-time costs for the 1st of class and the land-based engineering facility as well as PMO costs. There’s also some equipment inflation in the latest FY24 budget which I’m ignoring as this impacts all ships classes and should be stripped out when comparing to prior LCS or DDG costs on a constant dollar basis.

The actual follow-on ships themselves cost $900M.

 

[Scott Kenny]

I’m quoting official SCN budget materials so have 100% confidence in my numbers.

https://www.secnav.navy.mil/fmc/fmb/Documents/24pres/SCN_Book.pdf

It’s always a good idea to read the detail rather than take media reported numbers at face value… for example in this case the $1.2B quoted in news reports includes one-time costs for the 1st of class and the land-based engineering facility as well as PMO costs. There’s also some equipment inflation in the latest FY24 budget which I’m ignoring as this impacts all ships classes and should be stripped out when comparing to prior LCS or DDG costs on a constant dollar basis.

The actual follow-on ships themselves cost $900M.

I will never understand why onetime costs for a class get charged to the lead ship...

 

[Foo Fighter]

I suspect the real reason is to hide, shall we say, incentives? One time, tax free and nice if you can get it too.

 

[johnpjones1775]

Not sure how much this will cost, but this is the sort of frigate I think the USN needs.

New Details On Taiwan’s Future Light Frigate - Naval News

The updated design of Taiwan’s New Light Frigate is larger and heavier in order to accommodate more weapon and sensor systems...

www.navalnews.com

 

[CV12Hornet]

The US Navy is not a coastal defense force like Taiwan's Navy and should not be procuring the same ships.

 

[SSgtC]

Not sure how much this will cost, but this is the sort of frigate I think the USN needs.

New Details On Taiwan’s Future Light Frigate - Naval News

The updated design of Taiwan’s New Light Frigate is larger and heavier in order to accommodate more weapon and sensor systems...

www.navalnews.com

Except the main justification that Taiwan is using for building two separate versions, is not having to integrate the ASW and AAW warfare systems into one functional combat control system. The US has already done that. They have literally no reason to build dedicated ships for a single mission

 

[H_K]

Not sure how much this will cost, but this is the sort of frigate I think the USN needs.

New Details On Taiwan’s Future Light Frigate - Naval News

The updated design of Taiwan’s New Light Frigate is larger and heavier in order to accommodate more weapon and sensor systems...

www.navalnews.com

Nothing new here that hasn’t already been done by others. E.g. Gowind class corvette / light frigate.

 

[Scott Kenny]

Not sure how much this will cost, but this is the sort of frigate I think the USN needs.

New Details On Taiwan’s Future Light Frigate - Naval News

The updated design of Taiwan’s New Light Frigate is larger and heavier in order to accommodate more weapon and sensor systems...

www.navalnews.com

A 3000ton ASW-only craft?

Too small. Even the FFG-7 class was noted for limited endurance, which means a larger ship for more fuel, food stores, and crew habitability space.

Plus, any convoy escort these days needs to be able to provide at least minimal area defenses, and the Tuo Chiang class only has 16x ESSM equivalents and no SM-2s.

 

[A Tentative Fleet Plan]

Gowind does it rather better. Of course given the situation Taiwan is in, I'd suggest they build minelayers and SSKs, light frigates are too limited in capability to be viable, and Taiwan can't really afford anything better. Should probably just use SSKs and minelayers, with the hope that the latter can do their job in the last days of peacetime before the balloon goes up.

 

[johnpjones1775]

A 3000ton ASW-only craft?

Too small. Even the FFG-7 class was noted for limited endurance, which means a larger ship for more fuel, food stores, and crew habitability space.

Plus, any convoy escort these days needs to be able to provide at least minimal area defenses, and the Tuo Chiang class only has 16x ESSM equivalents and no SM-2s.

Size says very little about range or endurance.
Heritage class cutter is 3700 tons and has a range of 10k nmi and endurance of 60 days

That’s double the range of a burke

 

[CV12Hornet]

Size says very little about range or endurance.
Heritage class cutter is 3700 tons and has a range of 10k nmi and endurance of 60 days

That’s double the range of a burke

Double the range of a Burke at a lower cruising speed, so the gap is closer than you seem to think.

Also, the Heritages are devoting a lot more space to fuel bunkerage than the Taiwanese frigate - that's obvious just comparing their weapons and sensor loads - and 700 tons heavier to boot, so I don't know why you're making this comparison in the first place.

 

[johnpjones1775]

Double the range of a Burke at a lower cruising speed, so the gap is closer than you seem to think.

Also, the Heritages are devoting a lot more space to fuel bunkerage than the Taiwanese frigate - that's obvious just comparing their weapons and sensor loads - and 700 tons heavier to boot, so I don't know why you're making this comparison in the first place.

Just pointing out an FFG at this size can have good range. Maybe not 10k nmi, but 4-5k nmi seems completely reasonable, plenty of range.

Scott said these frigates were too small to have a range that would be useful for the US. I was simply pointing out the size isn’t really that relevant to range.

 

[H_K]

Just pointing out an FFG at this size can have good range. Maybe not 10k nmi, but 4-5k nmi seems completely reasonable, plenty of range.

For sure. Even the 2,000 ton Sigma 9813 corvettes advertise ~4,000nm range @ 18 knots with 260m3 of fuel (~11% of displacement which is not unreasonable).

That would translate to 5,000nm+ at 15 knots and 6,000nm+ at 12 knots.

 

[H_K]

Coming back to the debate about long ranged light frigates, tailored in particular to the Indopac theater, and whether this is smart / affordable / feasible…

Here is a hypothetical Gowind patrol frigate (~3,100 tons) to replace the French Floreal class based overseas. There are rumors that the French Navy is looking at the Gowind 3100 platform for this role, rather than the clean sheet European Patrol Corvette. The idea is to leverage an existing design to reduce acquisition costs, with sufficient built-in ASW and AAW capability. Will be interesting to see what comes out of this… especially as this entails taking an existing short legged light combattant and turning it into an oceanic escort.

The main design change would be to simplify the propulsion to allow for more fuel bunkerage, at the cost of slightly reduced speed (24-25 knots). I’ve also hypothesized the addition of a few modern touches such as flat panel radar and a reverse angle bow… there would also likely be modular bays for a few 20ft containers or other payloads in the stern and amidships.

Compare to the Gowind 2500 corvette baseline:

Some back of the envelope math indicates that good range could be achieved with modern fuel efficient diesels and ~330 tons of onboard fuel (11% of displacement). Range would be roughly 7,500 nm @ 15kts or 9,500 nm @ 12kts, with a 20% reserve. The tradeoff would be lower top speed, likely ~24 knots sustained assuming a CODAD plant with 4x small medium speed diesels (eg. ABC 16V DZC, 4x 3.75MW, total 14MW) and ~25 knots sprint at full power.

(Note: The same design exercise could be done with the Meko A100, Sigma 10514, FCX 30, Daegu class or other off-the-shelf light frigates… I chose the Gowind since this is an actual program of record and more likely to become real)

 

[Foo Fighter]

OK, several reverse bow designs about, simple question, why?

 

[Scott Kenny]

OK, several reverse bow designs about, simple question, why?

Apparently has some improved seakeeping, though it does mean a wetter bow.

For example, North Sea oil rig supply vessels are sporting some variation on the reverse bow.

 

[Foo Fighter]

Apparently has some improved seakeeping, though it does mean a wetter bow.

For example, North Sea oil rig supply vessels are sporting some variation on the reverse bow.

Thanks mate.

 

[H_K]

OK, several reverse bow designs about, simple question, why?

Here’s a Naval Group paper summarizing the pros of reverse angle bows. According to them:

- Lower Radar Cross Section
- Cuts better through through medium sized waves (= less resistance, less slamming)
- Longer waterline = better for high speed, less pitching moment

https://www.atma.asso.fr/dyn/memoires/memoire_42.pdf

 

[Foo Fighter]

Thanks very much, more edjumucation is always good.