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The_Gill_738
07-28-2005, 11:50 AM
How do I determine the speed and distance of a contact with just the information from the hydrophone? Sorry for all the Newbie questions. I wanna bump up the realism as much as I can. Thanks.

The_Gill_738
07-28-2005, 11:50 AM
How do I determine the speed and distance of a contact with just the information from the hydrophone? Sorry for all the Newbie questions. I wanna bump up the realism as much as I can. Thanks.

aaronblood
07-28-2005, 12:12 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by The_Gill_738:
How do I determine the speed and distance of a contact with just the information from the hydrophone? Sorry for all the Newbie questions. I wanna bump up the realism as much as I can. Thanks. </div></BLOCKQUOTE>

Well, technically... with just hydro you can't get an accurate distance. If you have sonar you can ping the hydro contact for the distance.

However, if you have an idea on the heading and track of the target (ie. a radio contact) you could probably make a decent guess at it like this...

Assuming your sub is stationary...

Your sonar guy is gonna let you know if the contact is moving slow (6kts) or medium (9-10kts). If you plot the bearing from the sub and then wait 3.25 mins and plot a second bearing, you could use that info to see where the bearings are far enough apart to equate to 6kts. Granted, at this point you already have the plot from the radio contact so you're just sorta confirming the distance.

I need to spend a bit more time trying to use it against targets I find without the help of a radio plot to see if the method is usable with a total blind contact. I think I will be able to still do it just a tad more abstract to attempt to get a feel for the heading by just listening... so I'm speculating a bit.

As far as the radio contact method... I've also had some success allowing the sonar guy to track with the hydro and by the cadence and bearings given I can tell when I'm in the vacinity of 500-700m. I've been able to kill merchants at that distance without seein em in terrible 400m vis weather by using the bearing and general plot of their course and listening at scope depth and firing blind when the target gets to the 15â?-20â? bearing.

What's also interesting is I've been able to damage merchants beyond vis range and when fires start on their decks I can then see and finish the attack from the surface at 500-700m much easier and they certainly have no way to see me in 400m weather and attempt to counter with a deck gun.