Crazy Ivan maneuver in Red Storm Rising

[STURM]

Was the Crazy Ivan maneuver in the Hunt For Red October or Red Storm Rising simply conjured up by Tom Clancy for his book as something natural and logical any sub skipper would do from time to time, or did Soviet sub skippers actually perform this maneuver as a way of checking their stern?

 

[vivtho]

Was the Crazy Ivan maneuver in the Hunt For Red October or RedStorm Rising simply conjured up by Tom Clancy for his book as something natural and logical any sub skipper would do from time to time, or did Soviet sub skippers actually perform this maneuver as a way of checking their stern?

Bow-mounted sonars in submarines can only search a cone ahead of the boat and are virtually blind to their stern. Making a full circle from time to time is a standard practice amongst all submarine operators. The only reason why this has reduced in recent years is the increased prevalence of towed-array sonar systems which do away with the blind spot.

That said, the Crazy Ivan manoeuvre performed by Soviet submarines differed mainly in the sharp departure from the normal course. While the normal way of clearing the blind spot was to make a gentle wide turn (this gave the sonar operators more time), the Soviets used to perform sharp turns at random intervals. This was mainly to dissuade any shadowing submarines.

 

[gf0012-aust]

Was the Crazy Ivan maneuver in the Hunt For Red October or RedStorm Rising simply conjured up by Tom Clancy for his book as something natural and logical any sub skipper would do from time to time, or did Soviet sub skippers actually perform this maneuver as a way of checking their stern?

No, The manouvre was described by one of the crewman in a history published about USS Parche - many years before Clancy espoused it.

 

[aussienscale]

A simular thing is also used by surface ships in screening which is called Zig Zag Manouvre in high submarine threat areas. Designed to basically make it hard for submarines to gain a firing solution

 

[STURM]

A simular thing is also used by surface ships in screening which is called Zig Zag Manouvre in high submarine threat areas. Designed to basically make it hard for submarines to gain a firing solution

No doubt a Zig Zag Manouvre would be useful if a sub was still using straight running torps but against acoustic torps would the Zig Zag Manouvre still be useful?

Also, what was the idea behind 'sprint and drift' tactics? Was it simply to allow sonar operators a better chance of detecting something?

 

[aussienscale]

No doubt a Zig Zag Manouvre would be useful if a sub was still using straight running torps but against acoustic torps would the Zig Zag Manouvre still be useful?

Sort of, back in WWII days, but the idea of a Zig Zag is for the screened ship to carry it out, no use in a ship on its own in the middle of the oggen to go solo, so the asset/s you wish to protect form the centre of the TG and are the ones to carry out the Zig Zag procedure (of which there are many variations depending on the tactical situation/threat) ships are then assigned a sector within that screen which is maintained relative to heading and speed of the protected unit/s. From there there are many variations depending on what you are protecting and their capabilities, the perceived threat, known threat, the capabilities and assets (eg towed array, decoys, air assetts etc) and the purpose of the mission etc etc.

So on the outside it can look like an outdated system/method, but like all things when you take into account systems, assetts, capability, comms etc etc it is still a very effective tool, there is then procedures for the ships in the individual sectors on how they patrol the sector, what systems and procedures they use in there rold and how the system/procedure works as a whole

 

[localhost127]

That said, the Crazy Ivan manoeuvre performed by Soviet submarines differed mainly in the sharp departure from the normal course. While the normal way of clearing the blind spot was to make a gentle wide turn (this gave the sonar operators more time), the Soviets used to perform sharp turns at random intervals. This was mainly to dissuade any shadowing submarines.

how slow would the turn have to be so that passive sensors are still effective?

 

[vivtho]

how slow would the turn have to be so that passive sensors are still effective?

I haven't heard of any concrete figures in that regard as that would be very sensitive information that no navy would like to disclose. But I expect that the exact time would vary depending on the exact type of sonar and submarine.

On a different note, I forgot to mention that even submarines with towed arrays perform a similar manoeuvre but the purpose is different. With a towed array at maximum extension and a large turn radius this manoeuvre allows the submarine to listen to itself, checking for any engine or transient sounds.

 

[STURM]

how slow would the turn have to be so that passive sensors are still effective?

The Crazy Ivan was meant to be conductedly quite rapidly, hence the name.

With a towed array at maximum extension and a large turn radius this manoeuvre allows the submarine to listen to itself, checking for any engine or transient sounds.

Interesting, I would never have thought of that!

Assuming the towed array was fully or even partly extended, it would probably take a few minutes to get back into position, after a maneuver or a turn.

 

[localhost127]

On a different note, I forgot to mention that even submarines with towed arrays perform a similar manoeuvre but the purpose is different. With a towed array at maximum extension and a large turn radius this manoeuvre allows the submarine to listen to itself, checking for any engine or transient sounds.

thanks!

 

[My2Cents]

Also, what was the idea behind 'sprint and drift' tactics? Was it simply to allow sonar operators a better chance of detecting something?

The faster you go the more noise is generated by the water flowing over your hull, which will mask the sounds you are trying to detect. Above a certain speed, which depends on a number of design details and the noise radiated by the target you are trying to detect, the only way to sense the target is to ram it.

The idea with ‘sprint and drift’ is to move rapidly to a new location then stop and drift to maximize the sensitivity and effective range of the sonar. It is useful for cover a distance faster than a slow speed run, or to generate an offset to estimate range to target. In some ways it is like an infantryman in cover looking around for the enemy, then sprinting to the next piece of cover and looking around again.

If you already have an target detected, and are trying to remain undetected, slow even movement is a better choice than sprint and drift, unless everyone else is moving too fast for good detection.

 

[STURM]

My2Cents,

Thanks, now I know what what 'sprint and drift' is all about. Much appreciated .

Does reeling out a towed array and reeling it back in generate a lot of noise or is it relatively noiseless?

 

[vivtho]

The Crazy Ivan was meant to be conductedly quite rapidly, hence the name.



Interesting, I would never have thought of that!

Assuming the towed array was fully or even partly extended, it would probably take a few minutes to get back into position, after a maneuver or a turn.

Very very rough back of the envelope calculations tell me that a 3000 foot towed array (IIRC most first generation towed arrays were 1000-1500 feet long) will allow the sub to check its signature from just under a thousand feet. Some more rough calculations seem to indicate that such an array will require about 6-10 minutes to straighten out.

 

[vivtho]

The faster you go the more noise is generated by the water flowing over your hull, which will mask the sounds you are trying to detect. Above a certain speed, which depends on a number of design details and the noise radiated by the target you are trying to detect, the only way to sense the target is to ram it.

The idea with ‘sprint and drift’ is to move rapidly to a new location then stop and drift to maximize the sensitivity and effective range of the sonar. It is useful for cover a distance faster than a slow speed run, or to generate an offset to estimate range to target. In some ways it is like an infantryman in cover looking around for the enemy, then sprinting to the next piece of cover and looking around again.

If you already have an target detected, and are trying to remain undetected, slow even movement is a better choice than sprint and drift, unless everyone else is moving too fast for good detection.

To add to what you've said....

IIRC the noise of water flowing across the bow of the submarine increases with the square of the speed. So this maximum quiet speed will vary depending on the hull design, propeller design, powerplant (electric, nuclear active circulation or nuclear passive circulation), depth and a variety of environmental factors. One of the reasons why submarines prefer sprint and drift is that frequently, their maximum 'quiet' speed is much faster than their ideal 'sonar quality' speed

So to maximize the average speed the commander of the submarine will use a combination of (comparatively) high-speed runs with slow speed drifting. The duration of these runs would usually depend on the exact performance of the sonar system ... the longer the effective range of the sonar the longer he can afford to run at high speed before nearing the next 'blind' area.

 

[vivtho]

My2Cents,

Thanks, now I know what what 'sprint and drift' is all about. Much appreciated .

Does reeling out a towed array and reeling it back in generate a lot of noise or is it relatively noiseless?

It depends on what your definition of 'lot' is
Any mechanical noise is transmitted a lot further underwater than can easily be appreciated. So compared to the sound of blowing the tanks or a cavitating propeller, the towed array is a lot quieter. But if you compare it to the sound of a reactor at low power it's quite a bit louder.

Also, when you're talking about sounds you should also define the range ... in the example above at short range the towed array will be louder and much more easily distinguishable from the reactor noise because of its higher frequency. But as the range increases, the reactor would still be audible (however faintly) while the array wouldn't.

 

[localhost127]

can anyone recommend books on the subject? active and/or passive sonar, tactics, etc. anything i can get my hands on would be appreciated.

 

[vivtho]

can anyone recommend books on the subject? active and/or passive sonar, tactics, etc. anything i can get my hands on would be appreciated.

I can't actually recommend any single book ... I'll leave that to the other posters here.

I can recommend a classic game though - Janes simulation 688(I) Hunter/Killer ... it's available on Steam and is a decent submarine simulator. While I've seen other more realistic sims than this, most of them focus on WW2 submarines while 688i is (comparatively) more current. You might want to check if it runs on modern computers though ... I ended up running it in a Virtual Machine as it doesn't support Windows 7 64bit.

 

[Humming Drone]

To add to what you've said....

IIRC the noise of water flowing across the bow of the submarine increases with the square of the speed. So this maximum quiet speed will vary depending on the hull design, propeller design, powerplant (electric, nuclear active circulation or nuclear passive circulation), depth and a variety of environmental factors. One of the reasons why submarines prefer sprint and drift is that frequently, their maximum 'quiet' speed is much faster than their ideal 'sonar quality' speed

So to maximize the average speed the commander of the submarine will use a combination of (comparatively) high-speed runs with slow speed drifting. The duration of these runs would usually depend on the exact performance of the sonar system ... the longer the effective range of the sonar the longer he can afford to run at high speed before nearing the next 'blind' area.

Submarines prefer "sprint and drift"? Why would you possibly do that in a submarine if you already have an advantage? Surface ships, on the other hand, can benefit from this tactic because 1) a sub tracking a ship would have a tougher time getting and maintaining a firing solution and 2) if a sub wants to keep up with a surface ship, it will have to increase it's own speed (read: become noisier and hamper it own detection capabilities) and if the sub does not time its own stop from the sprint then you will have a surface ship already in a drift listening attentively if anyone is chasing it and the sub chugging along giving itself away. That's not even considering the option of a anti-sub helicopter sitting around and waiting for the sub to make its move, or two ships working in tandem, or two ships and 1-2 helicopters...

 

[vivtho]

Submarines prefer "sprint and drift"? Why would you possibly do that in a submarine if you already have an advantage? Surface ships, on the other hand, can benefit from this tactic because 1) a sub tracking a ship would have a tougher time getting and maintaining a firing solution and 2) if a sub wants to keep up with a surface ship, it will have to increase it's own speed (read: become noisier and hamper it own detection capabilities) and if the sub does not time its own stop from the sprint then you will have a surface ship already in a drift listening attentively if anyone is chasing it and the sub chugging along giving itself away. That's not even considering the option of a anti-sub helicopter sitting around and waiting for the sub to make its move, or two ships working in tandem, or two ships and 1-2 helicopters...

I think you're only considering the scenario where the submarine is close to hostile surface vessels.
If a submarine has to cover a distance safely and quickly, depending on the threat situation the commander might choose one of a variety of options

Let's take a look at a scenario where the submarine has to cover a distance of 100 nm
1) If the commander covers the entire distance at full speed (30 kts) he can probably reach the destination in 3.5 hours. But he will be completely deaf and blind for the entire trip.
2) The safest option is to proceed at his best quiet speed (5 kts) but then the journey will take 20 hours
3) If he sprints (20 kts) and drifts (5 kts) for alternate half hour segments then the entire journey can be completed in 8 hours while still having a decent idea about what's going on around the submarine.

When close to a surface ship then timing does become a problem, but that's where the commander of the sub has to make a judgement call. He can either continue running slow and silent and risk loosing out on a target or take a risk and sprint for a short while to get to an unexpected position. Flow noise takes a while to settle down as the ship/sub reduces speed and a submarines is usually in a better position to detect whether the surface ship is coming off a sprint and reduce speed accordingly.

Multiple assets prosecuting a submarine does not necessarily mean that the sub has no chance. The tactical situation will depend on a lot of factors, the nature of the threats and so on.

 

[STURM]

can anyone recommend books on the subject? active and/or passive sonar, tactics, etc. anything i can get my hands on would be appreciated.

There are practically no detailed books no modern sub warfare, never mind detailed stuff on sonars, which manufacturers may not want published but even on modern ASW tactics. A lot on the market still consists of general and coffee table books on subs and ASW. No doubt certain navies publish a lot of detailed stuff which is not available for public release. I'm not sure if the Submarine League is till around. It used to publish its own mag which was available for subscription. Funny enough, the operatind manuals/booklets of certain sub sims have very interesting and detailed info, not found on many books.

It depends on what your definition of 'lot' is

True. What I meant was does a sub which is in the process of reeling in or out a towed array, generate enough noise for it to be picked up by the sonar of another sub or sonarbuoys laid by aircraft , in the way opening tube doors can. I would imagine that even the process of loading torps into tubes can be picked up on sonar.

I very curious as to how surface ships and subs actually record acoustic signatures. Is it the gear standard on sonar suites or is it bought separately?

Does anyone know if India has sent any of its skippers to attend the RN perisher course? Another navy which conducts a similar course, which is open for foreign navies, is Holland. There was a report in Janes Weekly that came out in the late 80's about the Canadian navy having problems finding skippers of the Upholder class as the first bacth it sebnt to the UK had failed the Perisher course.