How Sonar Works(Nuclear Submarine)

[truthfollower]

How Sonar Works (SUBMARINE SHADOW ZONE)

Bearing rate graph

If graph is a straight line, it could mean they know your location and they are coming to say hello

bearing graph with multiple things

multipath

SVP

Convergence zone

Sonar waves bouncing just like light in fiber optic cable

ES310
Introduction to Naval Weapons Engineering
(reference website in the video)

Sonar Propagation

@PanzerKiel
@Rashid Mahmood

 

[FuturePAF]

Beat you to it on the multimedia sub-forum, but you added some good pictures

How Sonar Works

A very informative video to understand how sonar works and how difficult the work of submariners truly is. Here is document he’s talking about if your interested in reading it https://fas.org/man/dod-101/navy/docs/es310/SNR_PROP/snr_prop.htm

defence.pk

 

[truthfollower]

Beat you to it on the multimedia sub-forum, but you added some good pictures

hahaha nice i was taking screenshots

 

[FuturePAF]

hahaha nice i was taking screenshots

I appreciate the screenshots. Never really understood how difficult submarine sonar guys had it until I saw this video by Dustin.

I would have though they could display the data in a 3D form on a big screen in the command center of the submarine; to make it easier to understand and use, but I guess they stick to the basics to stay sharp, and not get comfortable.

P.S. I hope the PN has mapped out the shadow zones in our and the enemies EEZ.

 

[truthfollower]

what is the speed of sonar wave? how accurate it is for targeting?

 

[Rashid Mahmood]

Thanks for sharing.

The most difficult operation is ASW.

On paper, seems easy, but in actual it is the most technical and unpredictable ops.
Sound waves behaviour underwater is the most difficult to assess.

We sometimes knew the subs position and depth, but the sonar couldn't pick it up, and sometimes it could be picked up from more than the designed active ranges.

AIP Subs have an advantage of being quieter than the boomers, so they can hide easily under the layers.

 

[SQ8]

Thanks for sharing.

The most difficult operation is ASW.

On paper, seems easy, but in actual it is the most technical and unpredictable ops.
Sound waves behaviour underwater is the most difficult to assess.

We sometimes knew the subs position and depth, but the sonar couldn't pick it up, and sometimes it could be picked up from more than the designed active ranges.

AIP Subs have an advantage of being quieter than the boomers, so they can hide easily under the layers.

How does the saline content of the Arabian sea affect the thermocline layers? I would think it’s slightly more difficult since its primary exchanges are the Indian ocean. Otherwise it has quite a few landmasses next to it.

 

[Rashid Mahmood]

How does the saline content of the Arabian sea affect the thermocline layers? I would think it’s slightly more difficult since its primary exchanges are the Indian ocean. Otherwise it has quite a few landmasses next to it.

Arabian sea is one of the most difficult areas to hunt for a sub.
The layers are unpredictable and change rapidly.

The Arabian Sea has a dense, high-salinity layer (37 parts per thousand) to a depth of about 400 feet (120 metres) because of high evaporation rates at subtropical temperatures with moderate seasonal variations. It is a haven for subs.


EXTRACT:
'During the pre-monsoon period, the entire Arabian Sea is characterized by a shallow thermocline (30–40 m) due to strong surface heating. Upwelling in the coastal regions and downwelling in the central Arabian Sea result in large variations in the thermocline topography during the south-west monsoon. This pattern reverses during winter when the surface currents reverse direction. The thermocline gradient is between 0.04°C m-1 and 0.14°C m-1 . An interesting result is the large variability in thermocline gradient (from 0.04°C m-1 near the coasts to 0.12°C m-1 in the central Arabian Sea) during July–September throughout the Arabian Sea. Weak gradients noticed in the northern Arabian Sea are due to the interaction of two different warm-water masses (the Arabian Sea and Persian Gulf water masses). The decrease in gradient in the equatorial Arabian Sea from January to June is attributed to the equatorial undercurrent which causes spreading of isotherms in the thermocline.

 

[SQ8]

Arabian is one of the most difficult areas to hunt for a sub.
The layers are unpredictable and change rapidly.

The Arabian Sea has a dense, high-salinity layer (37 parts per thousand) to a depth of about 400 feet (120 metres) because of high evaporation rates at subtropical temperatures with moderate seasonal variations. It is a haven for subs.


EXTRACT:
'During the pre-monsoon period, the entire Arabian Sea is characterized by a shallow thermocline (30–40 m) due to strong surface heating. Upwelling in the coastal regions and downwelling in the central Arabian Sea result in large variations in the thermocline topography during the south-west monsoon. This pattern reverses during winter when the surface currents reverse direction. The thermocline gradient is between 0.04°C m-1 and 0.14°C m-1 . An interesting result is the large variability in thermocline gradient (from 0.04°C m-1 near the coasts to 0.12°C m-1 in the central Arabian Sea) during July–September throughout the Arabian Sea. Weak gradients noticed in the northern Arabian Sea are due to the interaction of two different warm-water masses (the Arabian Sea and Persian Gulf water masses). The decrease in gradient in the equatorial Arabian Sea from January to June is attributed to the equatorial undercurrent which causes spreading of isotherms in the thermocline.

Thanks for that bit to affirm my longshot guess . I suppose it adds a greater challenge for our airborne sub hunters as well- I heard a rumor they would have to fly lower than most for MAD runs to try and ferret out our 90-Bs in training.
But then you may know better.

 

[Rashid Mahmood]

Thanks for that bit to affirm my longshot guess . I suppose it adds a greater challenge for our airborne sub hunters as well- I heard a rumor they would have to fly lower than most for MAD runs to try and ferret out our 90-Bs in training.
But then you may know better.

Yes the challenge is great in this area, but our ASW crew is well trained.
Good for our submariners as well.

MAD is a only a confirmatory sensor and not a locating sensor.

Active/passive sonobouys are the main sensors to locate subs from an LRMP.
Seakings have the dipping sonar for this purpose.

 

[truthfollower]

please help me understand is sonar part of electromagnetic spectrum? and whats the difference between these two

 

[Rashid Mahmood]

please help me understand is sonar part of electromagnetic spectrum? and whats the difference between these two

No, it is not part of EM spectrum.


EM Spectrum
The electromagnetic (EM) spectrum is the range of all types of EM radiation. Radiation is energy that travels and spreads out as it goes – the visible light that comes from a lamp in your house and the radio waves that come from a radio station are two types of electromagnetic radiation. The other types of EM radiation that make up the electromagnetic spectrum are microwaves, infrared light, ultraviolet light, X-rays and gamma-rays.

The EM spectrum is generally divided into seven regions, in order of decreasing wavelength and increasing energy and frequency. The common designations are: radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV), X-rays and gamma rays.

Sonar
Sonar, short for Sound Navigation and Ranging, is helpful for exploring and mapping the ocean because sound waves travel farther in the water than do radar and light waves. NOAA scientists primarily use sonar to develop nautical charts, locate underwater hazards to navigation, search for and map objects on the seafloor such as shipwrecks, and map the seafloor itself. There are two types of sonar—active and passive.

 

[baqai]

wow that was an interesting video, i ended up watching other videos of the chap as well, fascinating stuff