RFB needs your help re: decoys

[LukeFF]

Okay, here's the thing: we all know that American submarines, at one point in time or another, used some sort of contraption to spoof Japanese sonar. However, the only reference I've seen to an officially-used decoy (on these boards, at least) is in reference to the testing of a decoy in April 1945. Obviously, very late in the war and unlikely to have been deployed before war's end.

So, with that said, we (the RFB team) are debating about what to do with the whole decoy issue. Do we axe them completely or keep them in? Personally, I'm leaning towards getting rid of them completely, since it seems to be the case that no real, true, Navy-accepted decoy was employed on American submarines before war's end. If you have evidence to the contrary, please, make it known here so the RFB team can adjust the game files appropriately. Thanks!

[tomoose]

It seems SHIV simply grafted the SHIII type of decoy. I'm with you Luke, unless there's historical evidence of the same type of decoy being used more than a couple of times my vote is to axe it completely.

[M. Sarsfield]

The Batfish has a decoy launcher in the aft torpedo room (pretty small tube a few inches in diameter), but it was probably installed after the war.

[Rockin Robbins]

The decoys should walk the plank!

[mookiemookie]

Didn't Fluckey talk about using some sort of decoy in Thunder Below? Obviously it would be really late war, but I could have sworn he said something about it. Don't have the book in front of me to double check.

[M. Sarsfield]

The the sub sims from the early days, including SH1, let you jettison debris out of one of the torpedo tubes to fake your death. I'd would like to see that get added back in.

(I realize that this is off topic.)

[tater]

Roscoe mentions then as shipped on boats in November/December, 1944.

[AVGWarhawk]

Originally Posted by M. Sarsfield

The Batfish has a decoy launcher in the aft torpedo room (pretty small tube a few inches in diameter), but it was probably installed after the war.

Is that your signal flare tube? More than likely. It was not intended for decoy but I think was on the table as the launcher if a decoy would become available. It acts like a torpedo tube. I can not find any reference to the decoy actually making use during the war. I have read about shooting out articles from a torp tube. That is about it.

[M. Sarsfield]

Maybe it is a signal tube, except that it's pretty horizontal. I would expect a signal tube to be vertical, but I'm not proficient in all WWII sub euipment. The tube that I saw was next to and in front of the number 2 and 4 stern tubes sticking out of the port pressure hull. It sort of reminded me of a torpedo tube, but miniature. It wasn't perpendicular to the hull, but probably was angled at 30 degrees horiziontal and maybe 15 degrees vertical (down).

[AVGWarhawk]

Originally Posted by M. Sarsfield

Maybe it is a signal tube, except that it's pretty horizontal. I would expect a signal tube to be vertical, but I'm not proficient in all WWII sub euipment. The tube that I saw was next to and in front of the number 2 and 4 stern tubes sticking out of the port pressure hull. It sort of reminded me of a torpedo tube, but miniature. It wasn't perpendicular to the hull, but probably was angled at 30 degrees horiziontal and maybe 15 degrees vertical (down).

Yes sir, signal flare tube. It is the same on the Torsk. Certainly it could send out a decoy but I believe during the war it was not utilized for that. The tube was to send out a flare for a submarine in distress. Either submerged or surfaced.

http://www.heiszwolf.com/subs/torsk/torsk_torpedo.jpg

There is a large red A over the signal flare tube

[Mush Martin]

Lockwoods book has a mention of it but thats all I have.
I couldnt find it on Nav weaps either.

In Sink em all Adm. Lockwood writes.......

"While at pearl on the 19th, I took advantaqge of the opportunity
to see test runs of a secret decoy intended to aid submarines in evading counterattacks by escort vessels. Skate and the destroyer escort Whitman
put on the show and, after the submarine had acquired the technique,
she succeeded in eluding the DE in both of the final runs. This was a
gadget that I had first seen operating in a fresh water reservoir in
August,1944 abd fir which we had been preaying ever since. Its use
in enemy waters might have saved the sives of hundreds of submariners
and millions of dollars worth of submarines."


is Skates log available online somewhere? Ive lost my research links
temporarily

M

[M. Sarsfield]

There is a large red A over the signal flare tube

That's what I saw. It's nice to know what I'm looking at in the future.

I've been taking the virtual tour of the Pampanito to learn about the more obscure equipment like the fresh water tanks.

[capt_frank]

Look here, interesting read:

http://www.spawar.navy.mil/sti/publi...nrad50yre.html

"From 1943 to the end of the war, one of the highest priority tasks at the (San Diego) Laboratory was the NAC and NAD Sound Beacons, self-propelled sonar decoy devices that would enable U.S. submarines to evade Japanese sonar."

Sonar

Before 1943, the sonar school taught only how to operate and maintain the equipment. No one knew enough about sound in the ocean to teach anything about how to best use the sonar equipment.


The maximum effort and greatest contributions of both NRSL and UCDWR between 1941 and 1943 were in research. The physics of sound in the sea was not well understood. Sound propagation can be greatly affected by currents, marine organisms, water temperature, salinity, depth, and the structure of the ocean bottom. The San Diego Laboratory carried out studies and experiments on sound propagation, sound scattering, target strengths, ambient noise, etc. A brand-new science, entirely related to oceanography, had to be invented on a "crash basis."
This effort led to knowledge that the sonar schools and the Fleet could use to teach personnel how to use sonars to detect and attack submarines. The same knowledge was also used to teach U.S. submarines how to evade enemy sonar. During this time, information was also acquired for harbor defense, and an extensive series of charts of the Pacific was prepared by Laboratory oceanographers.

This broad knowledge base in such new categories then allowed development of equipment in 1944 to 1945 that led to important victories by the Fleet.
Fleet Support

Sound Decoy Devices

UCDWR scientists developed several sound decoy devices for submariners. Known as the NAC and NAD Sound Beacons, these self-propelled decoys emitted noises similar to U.S. submarines and could follow a preset course for 30 to 60 minutes. In 1945, NAD Sound Beacons were used by the Fleet to jam enemy sonars by transmitting echoes at exactly the same frequency as Japanese sonars.

[Wilcke]

Originally Posted by capt_frank

Look here, interesting read:

http://www.spawar.navy.mil/sti/publi...nrad50yre.html

"From 1943 to the end of the war, one of the highest priority tasks at the (San Diego) Laboratory was the NAC and NAD Sound Beacons, self-propelled sonar decoy devices that would enable U.S. submarines to evade Japanese sonar."

Sonar

Before 1943, the sonar school taught only how to operate and maintain the equipment. No one knew enough about sound in the ocean to teach anything about how to best use the sonar equipment.


The maximum effort and greatest contributions of both NRSL and UCDWR between 1941 and 1943 were in research. The physics of sound in the sea was not well understood. Sound propagation can be greatly affected by currents, marine organisms, water temperature, salinity, depth, and the structure of the ocean bottom. The San Diego Laboratory carried out studies and experiments on sound propagation, sound scattering, target strengths, ambient noise, etc. A brand-new science, entirely related to oceanography, had to be invented on a "crash basis."
This effort led to knowledge that the sonar schools and the Fleet could use to teach personnel how to use sonars to detect and attack submarines. The same knowledge was also used to teach U.S. submarines how to evade enemy sonar. During this time, information was also acquired for harbor defense, and an extensive series of charts of the Pacific was prepared by Laboratory oceanographers.

This broad knowledge base in such new categories then allowed development of equipment in 1944 to 1945 that led to important victories by the Fleet.
Fleet Support

Sound Decoy Devices

UCDWR scientists developed several sound decoy devices for submariners. Known as the NAC and NAD Sound Beacons, these self-propelled decoys emitted noises similar to U.S. submarines and could follow a preset course for 30 to 60 minutes. In 1945, NAD Sound Beacons were used by the Fleet to jam enemy sonars by transmitting echoes at exactly the same frequency as Japanese sonars.

So is this enough documentation to support their use in the sim for year '45? Were they deployed in '45 and in what boats? Would be nice to have if historically available! I

[M. Sarsfield]

30 to 60 minutes is a long time. We would have to model it after a torpedo, since the current decoys look like the u-boot pillenwerferen.