Home |
Search |
Today's Posts |
#1
posted to alt.sailing.asa
|
|||
|
|||
Another Stupid Whale
|
#2
posted to alt.sailing.asa
|
|||
|
|||
Another Stupid Whale
"Robert Musgine" wrote in message ... Are their brains the size of a golfball? http://www.cnn.com/2007/WORLD/americ...=ib_topstories Probably got its sense of direction screwed up by all the underwater sonar noise that submarines etc. are making these days. |
#3
posted to alt.sailing.asa
|
|||
|
|||
Another Stupid Whale
Dave wrote:
On Mon, 19 Nov 2007 16:48:45 +0100, "Edgar" said: Probably got its sense of direction screwed up by all the underwater sonar noise that submarines etc. are making these days. "These days" being the last 50 years? You know that sonar has changed quite a bit over the past 50 years? However even though transducer power has increased vastly thanks to modern electronics, the amount that active sonar gets used is also much less, again thanks to modern electronics and computational abilities. Why send out a massive ping that can be detected 500 miles away when you can quite nicely track a target 100 miles away using one ore more of your passive arrays? Alternatively, again because the listening side of the kit is so much better than 50 years ago, even if you have to go active, an extremly low power ping will do, (something that couldn't be done 50 years ago, you got a big ping, or no ping at all). Cheers Marty ------------ And now a word from our sponsor --------------------- For a secure high performance FTP using SSL/TLS encryption upgrade to SurgeFTP ---- See http://netwinsite.com/sponsor/sponsor_surgeftp.htm ---- |
#4
posted to alt.sailing.asa
|
|||
|
|||
Another Stupid Whale
"Martin Baxter" wrote in message
... Dave wrote: On Mon, 19 Nov 2007 16:48:45 +0100, "Edgar" said: Probably got its sense of direction screwed up by all the underwater sonar noise that submarines etc. are making these days. "These days" being the last 50 years? You know that sonar has changed quite a bit over the past 50 years? However even though transducer power has increased vastly thanks to modern electronics, the amount that active sonar gets used is also much less, again thanks to modern electronics and computational abilities. Why send out a massive ping that can be detected 500 miles away when you can quite nicely track a target 100 miles away using one ore more of your passive arrays? Alternatively, again because the listening side of the kit is so much better than 50 years ago, even if you have to go active, an extremly low power ping will do, (something that couldn't be done 50 years ago, you got a big ping, or no ping at all). Cheers Marty ------------ And now a word from our sponsor --------------------- For a secure high performance FTP using SSL/TLS encryption upgrade to SurgeFTP ---- See http://netwinsite.com/sponsor/sponsor_surgeftp.htm ---- I believe the US courts have blocked the military from using some of the sonar use, due to this issue. -- "j" ganz @@ www.sailnow.com |
#5
posted to alt.sailing.asa
|
|||
|
|||
Another Stupid Whale
"Martin Baxter" wrote in message ... Dave wrote: On Mon, 19 Nov 2007 16:48:45 +0100, "Edgar" said: Probably got its sense of direction screwed up by all the underwater sonar noise that submarines etc. are making these days. "These days" being the last 50 years? You know that sonar has changed quite a bit over the past 50 years? However even though transducer power has increased vastly thanks to modern electronics, the amount that active sonar gets used is also much less, again thanks to modern electronics and computational abilities. Why send out a massive ping that can be detected 500 miles away when you can quite nicely track a target 100 miles away using one ore more of your passive arrays? Alternatively, again because the listening side of the kit is so much better than 50 years ago, even if you have to go active, an extremly low power ping will do, (something that couldn't be done 50 years ago, you got a big ping, or no ping at all). Cheers Marty ------------ And now a word from our sponsor --------------------- For a secure high performance FTP using SSL/TLS encryption upgrade to SurgeFTP ---- See http://netwinsite.com/sponsor/sponsor_surgeftp.htm ---- Surface ships encounter a lot of noise to go passive unless they are using a VDS array such as the SQS-35. I've had the opportunity to see firsthand what the SQS-26 could do to marine mammals. The transmitted acoustic power of that sonar was 250,000 watts. It was so powerful you could here the reflection off of the bottom. We could turn it on and clear the harbor of any submarines. |
Thread Tools | Search this Thread |
Display Modes | |
|
|