question, in US SUB they use UZO?
 

Or something similar?

Thanks

It's called TBT
http://www.bowfin.org/website/educat..._frameset.html

The fleet boats had 2 mounted. 1 forward and one aft on the sail.

great!Thanks for response

Here's a corrected link for this: http://www.bowfin.org/website/bowfin...ms/TBT/tbt.htm

Good link with more info on the system.

http://www.maritime.org/fleetsub/elect/chap14.htm

I am not sure if the optics on the TBT were better than the german UZO but I do know that it was built much better that the UZO and did not require disassembly for dive. The germans had to take the UZO down every time they went to dive. The TBT was able to withstand the pressures of the dive. I think it was also capable to transmitting marks and bearing to target to the to the TDC electrically.

I've been running into some confusion on this myself. I just finished reading Peter Padfield's War Beneath The Sea, and he indicates that the TBT as shown in the manuals and the Bowfin site might actually be post-war developments (as shown by the Bowfin's 1946 date on the document). Padfield seems to think that the first TBTs were used in 1943, and were similar to the German UZO with a regular set of binoculars slotting into the transmitter station, and thus not waterproof.

I've always previously believed in the completely waterproof US device, probably spoiled by SH1. I'd be interested if anyone can come up with more detailed information, as currently I'm at a loss which to believe.

O'Kane mentions in his books of using the good old 7x50's clamped on the bearing transmitter. The 7x50 was the standard binocular at the time - I believe.

Take a look at the sites that Mookiemookie and Threadfin gave. The pictures and discription I think will cover what you are talking about. The TBT has a built in binocular of the high light transmission type (?) but the picture also shows a spot for binoculars to attach. I think one used one in conjunction with the other. The one that you attached assisted you in f"inding" a target and the one that was permently attached was used to "target" the target (having cross hairs) and then transmitting the information to the TDC.

Hope that helped.

Happy Hunting:ping:

No, it doesn't help. As I already said, both of the references given at those sites are dated 1946 - AFTER the war.

On the other hand, cmdrk's reference to O'Kane's book is a start.

I think you're right Steve, that's my recollection as well. I provided that link more as an overview of how the system worked, and how it was linked from bridge to control room/TDC. But I definitely have the same impression as you, that it was more likely the skipper stuck his binocs on the mounts as the need arose, then went below with them upon diving.

There are several good sources showing the TBT mounts and even a few that show them mounted. The Mare Island pics are very valuable, it seems they photographed EVERYTHING during overhauls. The TBT units in the pictures match the ones in the links in the other posts in the thread. (1)

Most of the pictures show the Late war boats, with everything cut down and 2 TBT's mounted. One is forward, on the bridge, and the second is aft on a stand alone pedestal between the 40mm / 20mm mount and the SD radar mast.

One very interesting set of photos however, shows the USS Bashaw's conning tower. She is alongside a tender is Brisbane in August of 1944. She has her 2 TBT mounts in box sponsons on either side of the Bridge, not fore and aft. (2)

The reason for the Bino mount on the TBT was (IIRC) the TBT had pressure proof optics, but they were not the highest quality, and as they were constantly exposed, they got fairly grungy. Also (again IIRC) they had little or no magnification.


Sources:

1. U.S. Submarines through 1945. Norman Friedman, Naval institute press. PP 219, 235, 236.

2. U.S. Subs in action. Robert C. Stern, Squadron / signal publications. PP 40 and 41.

Two pictures of the fixed mounted TBTs on board of USS Cod

http://img177.imageshack.us/img177/7...0072ln1.th.jpg

http://img177.imageshack.us/img177/5...0071rx9.th.jpg

The TBT's are just what they are: Target BEARING Transmitters. Only the bearing is fed into the TDC. Range had to be obtained differently.

groetjes,

Good pics Gino, thank you. By the looks of them I'd say they were pretty much permanently affixed and not removed every time the sub submerged.