[FIXED] MAD detection of subs

[dvresic]

I've been using the Scenario Editor to check on MAD detection.
P3 Orion can detect subs down to their deepest depth>700feet.
This must be broken.
MAD detection is inversely reduced by distance squared. There's no way it would be able to pickup a sub at this depth.

[Raptorx7_slith]

What altitude is the P-3 at?

[Dimitris]

Can you post a link to a save file? Thanks!

[dvresic]

I uploaded the scen file.
I've tested this in multiple Northern Inferno scenarios though.
Aircraft are at 1000ft. with MAD

[dvresic]

This is the moment of detection where the P3 Orion detects with the MAD the 1100 foot deep sub.
How is this possible?

[thewood1]

I remember reading a study that under good conditions, a MAD system could detect down to 1500 ft. I'll see I can find the pdf in my files.

[michaelm75au]

The function, then, of airborne MAD equipment is to detect the submarine-caused anomaly in the earth's magnetic field. The depth at which a submarine can be detected is a function both of the size of the submarine and how close the sensor is flown to the surface of the water.

Source: http://defence.pk/threads/so-you-want-t ... z4NmU0yiJk

Another older article which shows some numbers (page 3 shows a table)
http://www.dtic.mil/dtic/tr/fulltext/u2/a081329.pdf

[thewood1]

That last link is the one I remember.

[thewood1]

ORIGINAL: dvresic

I've been using the Scenario Editor to check on MAD detection.
P3 Orion can detect subs down to their deepest depth>700feet.
This must be broken.
MAD detection is inversely reduced by distance squared. There's no way it would be able to pickup a sub at this depth.

Can I ask where your knowledge comes from? You seem pretty sure in your initial post. Five minutes with google showed me those parameters are at least within the realm of possibility.

I mean, you didn't come in asking how the MAD model works. You actually declared it broken. So I think you can at least show what sources you had to say its broken.

[dvresic]

I'd like to hear some input from the Developers on their MAD model. Short of that are there any submariners that can shed some light on this?
Yes surface conditions, speed of the detecting platform, alignment of the submarine to the magnetic field lines, composition and size of the submarine....but the depth I would assume would be the single most important factor in detection.
Does the game model all this? What factors influence MAD in game and to what extent?


Here's a quote from Wikipedia;

Operation
To reduce interference from electrical equipment or metal in the fuselage of the aircraft, the MAD sensor is placed at the end of a boom or on a towed aerodynamic device. Even so, the submarine must be very near the aircraft's position and close to the sea surface for detection of the anomaly, according to the Inverse Square Law (or Law of Inverse Squares). The size of the submarine, its hull composition and orientation determine the detection range. MAD devices are usually mounted on aircraft.

[thewood1]

My question is you said its broken...what's broken? Can you at least answer that instead of throwing wiki links around?

[Rory Noonan]

I ran some tests on this a while back. Using a helix to detect a LA class sub altitude and depth had a significant impact.

At a (helo) altitude of 1000ft a sub at -100ft was detected at 564m. At a depth of -500ft the sub was detected at 442m, and at -1000ft the sub was detected at 290m. This was consistent and repeatable.

Not sure if it's correct or not, but the model does seem to take depth into account.

[Dimitris]

Tried this now.

The maximum detection range of the CA/ASQ-508(V) MAD sensor is 1nm.

The detection check happens as the CP-140 is at 1000ft and the submarine is at 1312ft. The slant range between them is 0.60nm, well within the MAD sensor's range, so the detection happens.

Which, if any, of the above elements is unreasonable ?

[dvresic]

If this was realistic, that a P3 would get a MAD contact at a sub at any depth, well I don't think the Navies of the world would be spending as much time and money in ASW as they are.

In the game; a 30x30mile patrol box of a P3 with a loiter time of 3hours would detect a sub every single time. No matter what depth or speed. Simply by flying over it with MAD. The sub could be 1400 feet deep.

Therefore I think the model is broken.

Scenario after scenario. Subs sunk due to a MAD hit.

I've posted a scenario...2 US SSN's (LA and Virginia class )are trying to Break out/Break in thru the San Juan Straight. It's not Sonar that picks them up. In every case it's a P3 flying patrol overhead with MAD.

[Dimitris]

This doesn't answer the question. Which of the above steps that I listed is unreasonable?

Do you have any sources that MAD is unable to detect aircraft at large depth ?

Thanks.

[Sardaukar]

This was in 1945...so in my opinion, current detection ranges and depths are totally reasonable:

https://books.google.fi/books?id=nyYSER ... ep&f=false

It says that Japanese MAD could detect submarine 900 feet range. Patrol altitude 200 ft would allow detection to 700 ft.

As Sunburn said, modern MAD has detection range of 1 nm. So detections even deep are totally feasible.

[Zaslon]

ORIGINAL: Sunburn

Tried this now.

The maximum detection range of the CA/ASQ-508(V) MAD sensor is 1nm.

The detection check happens as the CP-140 is at 1000ft and the submarine is at 1312ft. The slant range between them is 0.60nm, well within the MAD sensor's range, so the detection happens.

Which, if any, of the above elements is unreasonable ?

That's all the input required for a MAD detection? range?

[Dimitris]

Slant range, plus modifiers for non-metallic construction. If you look at the DB there are no per-platform magnetic signatures.

[wild_Willie2]

During normal ASW operations operations there would also be numerous false contacts in any shallow patrol area due to wrecks, debris or magnetic minerals.

Maybe it would be a good idea to introduce false MAD contacts like "wrecks" or "iron garbage" in lieu of false sonar contracts. I don't think these would be hard to program into the game, it would just be a matter of creating a neutral underwater unit with zero speed and a high magnetic field.

W.

[mikmykWS]

Hi Guys

There are some planned sonar and sub mechanics improvements planed for the future but for moment the sub model is sufficient for what most people seem to want to do. If you'd like something added please put it in the request strings so we can get a sense of priority.

Thanks!

Mike