ASDIC Question

Sir Big Jugs · 04-08-09, 11:44 AM

Hi,

I'm currently reading a Swedish book on U-boat warfare in WWII called "Havets Vargar" (Wolves of the Sea) by Michael Tamelander and Jonas Hård af Segerstad.
Without going into too much detail about the book itself, I found the following (very roughly translated) footnote interesting:

Quote:

An ASDIC pulse can't be picked up by the human ear, but a small "click" sound might be heard inside when it hits the hull of a submerged submarine. The well known 'PING' from many U-boat films could actually only be heard by the escort's ASDIC operator.
The ASDIC receiver converted the returning ultrasound echo to a sound at ~1000Hz (where the human ear is most sensitive) in order to make it hearable to the ASDIC operator. This converted sound was the charasterictic 'PING'.

Can anyone confirm/deny this? The authors both have a reputation for being quite meticulous in their research, and having read other books by them I hold them quite high in this regard.

On the other hand, I would be surprised if this potential mistake hasn't have been caught earlier, so they're probably wrong.

Hope someone knows the answer!

Regards,
-SBJ

GoldenRivet · 04-08-09, 11:47 AM

From what i have read, there were several types of ASDIC used.

some of which were well within the human range of hearing. others were too high pitched for human ears to hear.

whether or not you hear the distinctive "ping" like we are all too familiar with depends on which type of ASDIC is being deployed against you

kaptkirkU4467 · 04-08-09, 12:07 PM

Oh..you can hear it.

Hans Goebler: U-505 Submariner
"two minutes later, the radioman shouted a report up to Zschech through the conning tower hatch, informing him of what we all could hear with our bare ears: we were being scanned by Asdic. The pause between each Asdic "ping" was rapidly getting shorter. They had obviously located us and were headed right towards us. "

Sailor Steve · 04-08-09, 01:08 PM

Some uboatmen have described it as sounding like a handful of gravel being thrown against the hull.

UberTorpedo · 04-08-09, 02:26 PM

Yep. Pretty much like these sounds http://files.filefront.com/Authentic.../fileinfo.html

GoldenRivet · 04-08-09, 02:52 PM

positively sickening sounds

04-08-09, 11:47 AM	#2
GoldenRivet Subsim Aviator Join Date: Mar 2007 Location: Texas Posts: 8,726 Downloads: 146 Uploads: 0	From what i have read, there were several types of ASDIC used. some of which were well within the human range of hearing. others were too high pitched for human ears to hear. whether or not you hear the distinctive "ping" like we are all too familiar with depends on which type of ASDIC is being deployed against you __________________

04-08-09, 12:07 PM	#3
kaptkirkU4467 Navy Dude Join Date: Jul 2002 Location: Ft.White Florida Posts: 178 Downloads: 18 Uploads: 0	Oh..you can hear it. Hans Goebler: U-505 Submariner "two minutes later, the radioman shouted a report up to Zschech through the conning tower hatch, informing him of what we all could hear with our bare ears: we were being scanned by Asdic. The pause between each Asdic "ping" was rapidly getting shorter. They had obviously located us and were headed right towards us. " __________________ G/K Worldwide: Making your life miserable since 2002 ! K.R.A.P. http://www.subsim.com/radioroom/forumdisplay.php?f=240

04-08-09, 01:08 PM	#4
Sailor Steve Eternal Patrol Join Date: Nov 2002 Location: High in the mountains of Utah Posts: 50,369 Downloads: 745 Uploads: 249	Some uboatmen have described it as sounding like a handful of gravel being thrown against the hull. __________________ “Never do anything you can't take back.” —Rocky Russo

04-08-09, 02:26 PM	#5
UberTorpedo Planesman Join Date: Jun 2006 Location: Southern California Posts: 194 Downloads: 78 Uploads: 0	Yep. Pretty much like these sounds http://files.filefront.com/Authentic.../fileinfo.html __________________ Download Link for Mods and Other Goodies...

04-08-09, 02:52 PM	#6
GoldenRivet Subsim Aviator Join Date: Mar 2007 Location: Texas Posts: 8,726 Downloads: 146 Uploads: 0	positively sickening sounds __________________