How does the sub avoid cutting towed array?

PurpleCow · 07-12-17, 04:02 PM

The 688 sub looks like the propeller is not shrouded. How to they avoid cutting their own towed array cable during turns?

FPSchazly · 07-12-17, 04:20 PM

It probably could be, I'm sure there's a maneuvering envelope in real life to avoid cutting it. It seems like it's set up that it doesn't get cut, though, in most circumstances where one would use a towed. If you look at it, the sub turns but it's still moving forward at the same time. If you watch the towed, you can see it goes through the same spot where the previous section was until it straightens out.

Aktungbby · 07-12-17, 05:57 PM

Quote:

Originally Posted by PurpleCow

The 688 sub looks like the propeller is not shrouded. How to they avoid cutting their own towed array cable during turns?

It is not mounted near the propeller; in effect, every individual sub works out it's own operational procedures and maneuvering limitations during training.

Quote:

Effective use of the towed array system requires a vessel to maintain a straight, level course over a data sampling interval. Maneuvering, or changing course, disturbs the array and interrupts the sampled data stream. These periods of instability are closely tested during sea trials and known by the crew's officers and enlisted sonar experts. Modern systems compensate by constantly self-measuring the relative positions of the array, element to element, reporting back data that can be automatically corrected for curvatures by computers as part of the beamforming math processing.
A ship must also limit its overall top speed while a towed array is deployed. Hydrodynamic drag increases as a square function of velocity, and could tear the cable or damage its mooring hardware. Furthermore, a minimum speed may have to be established depending on the buoyancy of the towed array. The array could also be damaged by contact with the seafloor or if the vessel operates astern propulsion, or can even be damaged if it bends too tightly.

< on an Akula the array is mounted in the vertical fin teardrop. TB-29 array on US sub>

in detail>

http://www.militaryaerospace.com/articles/2015/04/nextgen-sonar-arrays.html

yubba · 07-18-17, 12:52 PM

Un like NASCAR right turn only with starboard array

A-Ganger · 07-19-17, 04:10 PM

If you go flank (31 kts 688) in RA 1.42 the wire will be gone..

Ask me how I know lol

07-12-17, 04:02 PM	#1
PurpleCow A-ganger Join Date: Nov 2004 Posts: 75 Downloads: 23 Uploads: 0	How does the sub avoid cutting towed array? The 688 sub looks like the propeller is not shrouded. How to they avoid cutting their own towed array cable during turns?

07-12-17, 04:20 PM	#2
FPSchazly Good Hunting! Join Date: Apr 2014 Location: Beantown Posts: 776 Downloads: 15 Uploads: 1	It probably could be, I'm sure there's a maneuvering envelope in real life to avoid cutting it. It seems like it's set up that it doesn't get cut, though, in most circumstances where one would use a towed. If you look at it, the sub turns but it's still moving forward at the same time. If you watch the towed, you can see it goes through the same spot where the previous section was until it straightens out. __________________ Your friendly neighborhood modern submarine YouTuber. My videos: Exclusive Look at Modern Naval Warfare! Dangerous Waters Liu Doctrine (LwAmi Learn to play Dangerous Waters

07-18-17, 12:52 PM	#4
yubba Admiral Join Date: Sep 2009 Location: in a neighborhood near you Posts: 2,478 Downloads: 293 Uploads: 2	Un like NASCAR right turn only with starboard array

07-19-17, 04:10 PM	#5
A-Ganger Sparky Join Date: Jul 2017 Posts: 158 Downloads: 13 Uploads: 0	If you go flank (31 kts 688) in RA 1.42 the wire will be gone.. Ask me how I know lol