Rumoured "mini-nuke/diesel" Submarine SSK-N(?) thread

[FairAndUnbiased]

You refused to acknowledge the limitations of physics when I pointed out the inevitable range limitations of any missile encased in a shell that ALSO has to incorporate a swim-out system. Your response was essentially "I just pointed to an example; I don't need to acknowledge the inherent range limitations involved". Well you do have to deal with it.

You also have to deal with the fact that the more neutral buoyancy you put into that capsule therefore further delaying the firing of the missile motor, the further the target ship will be traveling away from your sub, and at a much faster rate than your sub can egress from that same location. The math doesn't even add up and you also refused to acknowledge that, instead saying "well it's actually just a mine, really". ROFLMAO


As for the Mk48 swim-out upgrade, it makes no difference to my argument, since I was talking about the noise the torpedo makes while inbound to its target. I have already noted that torpedo LAUNCHES even without the swim-out upgrade are possibly going to be quieter than VLS launches. How much difference there is between these two types of weapon launches is not known to anyone of us here, you included.

For the numbers I arbitrarly picked but for some reason you are fixated on, a 30 min delay means that even a 30 kt destroyer moving full speed in a straight line away can only further increase its distance from launch point by 15 nm or 30 km. There is no radius of uncertainty since the destroyer is visible to the sub from passive sonar, only an engagement radius.

As for whether the 19 nmi range is a fundamental physical limitation of a swimout canister or a problem with Iranian engineering that can be fixed, note that a Harpoon missile with 140 km range has mass = 691 kg, L = 4.6 m with surface booster, OD = 34 cm with 691 kg total mass.

Mk 48 has payload alone of 293 kg, L = 5.8 m, OD = 53 cm. Harpoon sized and performance missile easily fits inside.

if you had a Mk 48 form factor swimout canister for the Harpoon style missile, you'd have to sacrifice some fuel and the payload. Let's call it a crawling speed swimout at 10 kts (20 kph) which is 1/5 the cruise speed of the Mk 48.

Since kinetic energy E=(1/2)mv^2, and in swimout mode all E comes from the fuel, E-m48 = (1/2)m(v-m48)^2 and with a crawling swimout E-canister = (1/2)m(1/5 × v-m48)^2 = 1/25 E-m48.

So a swimout canister going 10 kts requires only 1/25 the fuel as a swimout torpedo going 50 kts.

A Harpoon form factor missile fits. Plenty of fuel. 10 kts (20 kph) swimout for 30 min introduces 10 km of additional radial uncertainty on top of the sub's own 10 km of radial uncertainty on a 10 kt crawl. Target cannot leave engagement area of a Harpoon performance missile even if its a destroyer with a 30 kt cruise speed.

Guess the details favor me.

Sources:

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[Iron Man]

For the numbers I arbitrarly picked but for some reason you are fixated on, a 30 min delay means that even a 30 kt destroyer moving full speed in a straight line away can only further increase its distance from launch point by 15 nm or 30 km. There is no radius of uncertainty since the destroyer is visible to the sub from passive sonar, only an engagement radius.

As for whether the 19 nmi range is a fundamental physical limitation of a swimout canister or a problem with Iranian engineering that can be fixed, note that a Harpoon missile with 140 km range has mass = 691 kg, L = 4.6 m with surface booster, OD = 34 cm with 691 kg total mass.

Mk 48 has payload alone of 293 kg, L = 5.8 m, OD = 53 cm. Harpoon sized and performance missile easily fits inside.

if you had a Mk 48 form factor swimout canister for the Harpoon style missile, you'd have to sacrifice some fuel and the payload. Let's call it a crawling speed swimout at 10 kts (20 kph) which is 1/5 the cruise speed of the Mk 48.

Since kinetic energy E=(1/2)mv^2, and in swimout mode all E comes from the fuel, E-m48 = (1/2)m(v-m48)^2 and with a crawling swimout E-canister = (1/2)m(1/5 × v-m48)^2 = 1/25 E-m48.

So a swimout canister going 10 kts requires only 1/25 the fuel as a swimout torpedo going 50 kts.

A Harpoon form factor missile fits. Plenty of fuel. 10 kts (20 kph) swimout for 30 min introduces 10 km of additional radial uncertainty on top of the sub's own 10 km of radial uncertainty on a 10 kt crawl. Target cannot leave engagement area of a Harpoon performance missile even if its a destroyer with a 30 kt cruise speed.

Guess the details favor me.

Sources:

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ROFLMAO sorry but your gorilla math does not impress me at all. You totally and conveniently failed to account for the extra non-fuel parts that are required for the actual swim-out motor, the mass and volume for which you do not even remotely have a clue about. This gaping hole renders your entire set of amateur "fuel" calculations irrelevant because you literally have no idea how much space you have to work with in terms of exactly how much volume you need to reduce a Harpoon-sized missile by to accommodate the swim-out motor and fuel and still fit into the form factor of a Mk 48 torpedo. Guess the details totally escape you.

 

[FairAndUnbiased]

ROFLMAO sorry but your gorilla math does not impress me at all. You totally and conveniently failed to account for the extra non-fuel parts that are required for the actual swim-out motor, the mass and volume for which you do not even remotely have a clue about. This gaping hole renders your entire set of amateur "fuel" calculations irrelevant because you literally have no idea how much space you have to work with in terms of exactly how much volume you need to reduce a Harpoon-sized missile by to accommodate the swim-out motor and fuel and still fit into the form factor of a Mk 48 torpedo. Guess the details totally escape you.

Now we're at "but you don't know this info about a specific nonpublic capability!" Yeah but neither do you.

Are my calculations amateur? Sure, I don't get paid to do this, but you don't have any calculations at all. You don't really know if your objections are quantitatively sound or not.

For instance you bring up mass, but Ek scales linearly with mass but to velocity squared. So you need 25x more added mass to negate the 5x lower velocity.

You bring up volume. Sure engine volume is unknown. But there's the fact that you need 25x less fuel for a 1/5 speed swimout motor rather than fast motor. Dimensions of a combustion engine are typically small compared to the fuel volume. So how much does engine volume matter vs. fuel tank volume? Based on known scaling laws, not much.

Example 1: 3 m L x 0.9 m OD Merlin engine vs. 70 m L x 3.7m OD Falcon 9 with 90% fuel fraction.

Example 2: automotive engine displacement measured in 1 L increments but gas tank volume measured in 10 L increments.

From a physical standpoint, it is becoming clear that your objections have few legs to stand on.

I must remind the neutral audience that I didn't start this. You attacked me first and I am only doing the bare minimum to provide education. You have made 0 quantitative arguments, only attacks.

 

[Iron Man]

Now we're at "but you don't know this info about a specific nonpublic capability!" Yeah but neither do you.

Are my calculations amateur? Sure, I don't get paid to do this, but you don't have any calculations at all. You don't really know if your objections are quantitatively sound or not.

For instance you bring up mass, but Ek scales linearly with mass but to velocity squared. So you need 25x more added mass to negate the 5x lower velocity.

You bring up volume. Sure engine volume is unknown. But there's the fact that you need 25x less fuel for a 1/5 speed swimout motor rather than fast motor. Dimensions of a combustion engine are typically small compared to the fuel volume. So how much does engine volume matter vs. fuel tank volume? Based on known scaling laws, not much.

Example 1: 3 m L x 0.9 m OD Merlin engine vs. 70 m L x 3.7m OD Falcon 9 with 90% fuel fraction.

Example 2: automotive engine displacement measured in 1 L increments but gas tank volume measured in 10 L increments.

From a physical standpoint, it is becoming clear that your objections have few legs to stand on.

So.... all this, just to say that you don't actually know? You could have said so in far less words. BTW, you also forgot to incorporate the air volume that you need for net positive buoyancy. Do you know this quantity? Another total black hole, yes?

I must remind the neutral audience that I didn't start this. You attacked me first and I am only doing the bare minimum to provide education. You have made 0 quantitative arguments, only attacks.

It's fairly sad that you view this as an "attack":

Torpedoes absolutely can be detected while they're inbound. Naval vessels have had various torpedo warning systems for decades. VLS probably makes more noise at the source but even then it depends on the mechanism of launch for the particular VLS system. SSKs are all nearly universally smaller than nuclear subs so it's not clear to me that they don't have VLS because VLS makes too much noise or if SSKs just don't have enough room for VLS.

What, like on your moral character or something? You were the one who started with the snide degrading remarks and yet YOU try to play the victim here. ROFLMAO