Slava class cruiser vs 3 hatsuyuki class destroyers

SsgtC

Banned
Can a helo provide mid course guidnace to harpoons ? If so maybe a helo could be positioned to "pop up" say 50 Km or so from the Slava to provide a mid course guidance update ?
Maybe. It depends on how the helo is equipped. If it has Link 16 or NTDS, probably. If it doesn't, no.
 
No. The latest version in service in 1987 was Block 1C, with a range of ~120km.

I thought the range in that year was ~100 miles, which I assume is understated by 50-100%. If the 1987 publicly stated range was ~120km I'd imagine the actual range was ~200km which when you add in waypoints for converging attacks would allow for attacks at 120km.

I'm thinking if two or more helicopters worked together and used ESM to locate the Slava from long range it might be quite hard for the Slava to engage the Helos with SAM's.

I suspect in practice this would depend on how good the ESM gear on the Japanese helicopters was, how powerful the radars and other emitters on the Slava were etc.. Still I think having three times as many surface and air borne sensor platforms will give the Japanese an advantage.
Can a helo provide mid course guidnace to harpoons ? If so maybe a helo could be positioned to "pop up" say 50 Km or so from the Slava to provide a mid course guidance update ?

This is pretty much how I'd envisage a stalk and attack, ship and helo ESM getting a general fix on the Slava, helped by the triangulation from multiple ships and helos and the final pop up and radar sweep from the helo radar to give exact coordinates for the harpoons to converge on. However I don't think the helo can give direct updates to the harpoons.

You may be right, 30 km does sound bad compared ot even WW2 standards - it's little more than the distance to the horizon from its highest point, the ship seems mostly to be covered in air search radars.

I have no doubt the air search radars have huge ranges, but only above the radar horizon of course, under it and even between sweeps and gaps in the emissions lobes are perfectly exploitable gap in coverage.
 

destiple

Banned
The Jap helos were primarily ASW ( carried ASW torpedoes)and the ones on soviet rocket ships primarily for OTH of their ASW or ASUW missiles
Can the SSN-12 also get guidance from recon platforms like Tu-95 and satellites ?
 

destiple

Banned
Not in theory. It has its own onboard seeker. In theory, you can fire it in the general direction of your target, and it will guide itself after that. But to ensure accuracy and to make sure it hits what you want it to, it's best to provide it with OTH tracking the whole way
so Harpoons ( of the late 1980s) range not supported by OTH targetting is like 70nm or so ?
without OTH can the Harpoon be used to attack ships in harbor ? when it is critical to distinguish say a destroyer from a tanker
 
so Harpoons ( of the late 1980s) range not supported by OTH targetting is like 70nm or so ?
without OTH can the Harpoon be used to attack ships in harbor ? when it is critical to distinguish say a destroyer from a tanker

Those issues are exactly what doomed the anti-ship Tomahawk, after half an hour of flight the radar picks up whatever is the biggest target and homes in on it.

The Harpoon's flight time was about 10 minutes which makes these problems far more manageable.
 

destiple

Banned
Those issues are exactly what doomed the anti-ship Tomahawk, after half an hour of flight the radar picks up whatever is the biggest target and homes in on it.

The Harpoon's flight time was about 10 minutes which makes these problems far more manageable.

10 min at mach 0.9 ? thats 180 km flight distance
 
The soviet SSM are supersonic but larger targets while Harpoon are true sea skimmers
If the released info on the missiles is correct... they supposedly work in "teams", one rocket pops up high in the air and uses its seaker to search for targets long range, the other missiles fly low, if the first missile is shot down another one flies up to provide targeting data for the other missiles. Tose missiles are huge, they're more like kamikaze unpiloted jets than missiles, there's lots of room for fancy equipment in them.
 
If the released info on the missiles is correct... they supposedly work in "teams", one rocket pops up high in the air and uses its seaker to search for targets long range, the other missiles fly low, if the first missile is shot down another one flies up to provide targeting data for the other missiles. Tose missiles are huge, they're more like kamikaze unpiloted jets than missiles, there's lots of room for fancy equipment in them.

All of those radar emissions from the high missile and data link transmission between missiles would be detectable by the ship's ESM. Of course this doesn't magically give them enough weapons to defeat a multiple missile onslaught.
 

SsgtC

Banned
All of those radar emissions from the high missile and data link transmission between missiles would be detectable by the ship's ESM. Of course this doesn't magically give them enough weapons to defeat a multiple missile onslaught.
Yeah, at best it lets the DDs tag one more missile each. So each ship is still gonna take two or three hits apiece. So now you go from "everybody dies" to "almost everybody dies."
 
Yeah, at best it lets the DDs tag one more missile each. So each ship is still gonna take two or three hits apiece. So now you go from "everybody dies" to "almost everybody dies."

Early warning might allow some sort of maneuvre that might increase the effectiveness of countermeasures and defences.
 
Without outside help the Slava will be limited to esm, its helicopter and the radar horizon of about 25 miles.

By 1987 the harpoon had a range well in excess of 250km. Missile range won't be half the problem search coverage is.
Re the radar range issue.. I'm not sure I would bet my life on the Slava only having an effective radar horizon to a target such as a destroyer of 25 miles in this scenario. It could be somewhat more. I have no idea if any extra detection range would be enough to make a difference.

Early warning might allow some sort of maneuvre that might increase the effectiveness of countermeasures and defences.

It may also depend on when the Slava launches. If the Slava is able to locate the DD's and fires first I believe the DD's are going to be in a world of hurt. If upon detecting the in bound harpoons the Slava basically launches a revenge salvo in the general direction of where they suspect the DD's are then the extra warning might be more helpful.

If the DD's can also use the info gained from their ESM to degrade the communication links between the missiles via jamming, and the Slava is relying on a few of the missiles finding the DD's and relaying the location to the others then the odds of at least some of the DD's surviving may go up.

Lots of what it's.
 
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Re the radar range issue.. I'm not sure I would bet my life on the Slava only having an effective radar horizon to a target such as a destroyer of 25 miles in this scenario. It could be somewhat more. I have no idea if any extra detection range would be enough to make a difference.

The power of the radar isn't the problem, the curvature of the earth is. If the Slava's radar is 50' high and the highest detectable point of a DDG is also 50' the radar horizon is 20 miles and the visual horizon 17.3 miles. Doubling the power of the radar won't make any difference, only raising the height of the radar will.

Here are a couple of RAN River class frigates with LW02 air search radars which will illustrate the point.

Yarra3.jpg

Swan3.jpg


Raising the radar 10 feet gives you a mile or so extra radar horizon.nhttp://members.home.nl/7seas/radcalc.htm The Slava looks pretty high, but even if it was 70' high its only going to get you 22 miles.

slava_class.jpg
 
The power of the radar isn't the problem, the curvature of the earth is. If the Slava's radar is 50' high and the highest detectable point of a DDG is also 50' the radar horizon is 20 miles and the visual horizon 17.3 miles. Doubling the power of the radar won't make any difference, only raising the height of the radar will.

Here are a couple of RAN River class frigates with LW02 air search radars which will illustrate the point.

Yarra3.jpg

Swan3.jpg


Raising the radar 10 feet gives you a mile or so extra radar horizon.nhttp://members.home.nl/7seas/radcalc.htm The Slava looks pretty high, but even if it was 70' high its only going to get you 22 miles.

slava_class.jpg
As I understand things... The typical text book radio horizon for nominal "line of site transmissons" is considered to be 4/3 of the optical horizon. At times nominal "line of site" radio waves can go further.

It is my understanding that powerful nominal "line of site "radar systems of the types typically fitted to large late Cold War era warships can at times have a certain degree of "over the horizon" capability. I've read some reasearch papers re this topic that lead me to believe this is by no means un heard of but not by any means guaranteed.

It is also my understanding that increasing the power will increase the likely hood of getting a certain amount of "over the horizon" performance.

Again I personally wouldn't want to bet my life on a large late Cold War era warship having a surface search radar that was limited to optical line of site range (or the nominal 4/3 of optical line of site figure.) If I was in a large metal war ship that wasn't designed to be stealthy I would be even more worried. If the warship I was in had tall metal masts with antennas on top (that may also reflect the radar transmissions of my opponent) I would be more worried.

If the opposing war ship had clues about where to look (perhaps by detecting radio transmissions to and from my helicopters) and focused their radar search on a narrow sector I would be even more worried.

But yes you may be very well be correct that in our hypothetical engagement surface search radar range may be limited.

Edit to add:

In the late Cold War era I recall reading of efforts being made to devise ways of detecting when radar ranges were likely to be "enhanced." If one side had this technology deployed on their warships and the other side didn't things could get even more interesting in our hyopthetical match up.
 
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Here's another bit on an American 80s surface search radar, they did have some over the horizon capability back then.
radar.JPG


Edit: Got it, here are some calculations and estimations for both the Russian MR-700 and the Japanese OPS-18 radars.
http://www.admiraltytrilogy.com/cic/Harpoon/Smarter Radars for Hpn.pdf

Radar-----detection of: large(RCS 100m²), medium(20m²), small(5), very small(0.1), stealthy(0.01)
MR-700 27/27/18/10/6
OPS-18 48/32/18/10/6

What kind of RCS both ships have is unclear, and the Russian large/medium detection range is the same, maybe an error?
 
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While surface search radar does hug the curvature of the earth a bit, it still only gets you 25% extra on a short range, those conditions where a radar can detect things at 100 miles are uncommon. In any case, freak events where a radar detects something at 100 miles are still well short of the P500s 300 mile range.
 
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