Cruisers Forum
 


Join CruisersForum Today

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 14-10-2018, 18:03   #1
Registered User

Join Date: May 2016
Location: Brisbane Qld Australia
Boat: Oram 39C 39.98 m
Posts: 16
Forwardscan cats and whales

Hi,

Looking to upgrade my nav electronics and interested in the Forwardscan. Prob the B&G Vulcan 7. I am after some advice on what really works or possible.

So due the numbers of whales on the Qld coast(and I assume everywhere) I am very concerned about hitting one especially at night. I even had to deviate round one in Moreton Bay near Peel the other day. It just sat there broadside to my bows. I thought the forwardscan sonar might pick them up? I'm surprised to find no discussion about this.

Also how shallow is the forward scan effective in? Could you be sailing in 2 meters(known waters) and detect less than a meter? None of the videos online cover this that I could find.

Where do you mount the transducer if you have no mini keels?

Any experience with these units or other is appreciated.

Any other tactics for whale avoidance too. Other than staying at home.

Cheers,

Paul.
__________________

moreton99 is offline   Reply With Quote
Old 14-10-2018, 18:24   #2
Registered User

Join Date: May 2016
Location: Brisbane Qld Australia
Boat: Oram 39C 39.98 m
Posts: 16
Re: Forwardscan cats and whales

Oh and just saw the Garmin Panoptix Forward. wow pricey but if it works be worth every cent.
https://explore.garmin.com/en-AU/panoptix/
__________________

moreton99 is offline   Reply With Quote
Old 14-10-2018, 19:05   #3
Registered User

Join Date: Jan 2014
Location: Sydney, NSW
Boat: FreeFlow 50 cat
Posts: 928
Unhappy Re: Forwardscan cats and whales

Hi Paul,

I just got one from Southern Seas Marine at Coomera ( super helpful guys by the way) and they don't set the expectation that you can see surface objects whether it is whales or logs etc. It is better for seeing reefs/rock approaching in murky waters where eye balling is not going to work.

The transducer is a 45* angled face that faces forwards and it is not recommended that you keep it in place all the time, but only when you need it, because it would be vulnerable to an impact with floating objects. There is a flush plug for the hole when not needing the transducer. So you can locate it in an exposed position as far forward as possible.

Re sailing with whales at night, one guy I talked to put a speaker against his hull and played Meatloaf into the water. They have acute hearing and that may give them a heads up that you are approaching. I know I would avoid Meatloaf music, so maybe it works with whales too.
BigBeakie is offline   Reply With Quote
Old 14-10-2018, 19:43   #4
Registered User

Join Date: May 2016
Location: Brisbane Qld Australia
Boat: Oram 39C 39.98 m
Posts: 16
Re: Forwardscan cats and whales

I was thinking that the forward sounder pulses might help let the whales know where we are?

Whilst not a hater of Meatloaf it might wear a bit thin over and over on an overnight passage.
moreton99 is offline   Reply With Quote
Old 14-10-2018, 20:42   #5
Senior Cruiser

Cruisers Forum Supporter

Join Date: Jul 2005
Location: Bellingham
Boat: Outbound 44
Posts: 6,022
Re: Forwardscan cats and whales

Forward scan is of no use for whales or partially submerged objects offshore. It is for slow speed poking around potential anchorage. For that it is very useful.
__________________
Paul
Paul L is online now   Reply With Quote
Old 15-10-2018, 10:04   #6
Registered User

Join Date: Aug 2011
Location: New York, New York
Boat: Dufour Safari 27'
Posts: 734
Re: Forwardscan cats and whales

As others have said, it best used when moving slowly. Several units I've seen show an image out to 60 feet (18 meters) in the best of circumstances. Even at just 3 knots, that only gives one just under 12 seconds before one goes bump.
ArmyDaveNY is offline   Reply With Quote
Old 15-10-2018, 10:26   #7
Registered User
 
S/V Alchemy's Avatar

Join Date: May 2008
Location: Toronto
Boat: Custom 41' Steel Pilothouse Cutter
Posts: 4,837
Re: Forwardscan cats and whales

I actually have this setup: a Navico forward-scanning depthfinder and a B&G Vulcan 7, which I installed last year. The forward-scanning function is related to depth and I have found the maximum I can "see" objects like shoals and seawalls ahead of me ranges from 4 to 7 or 8 times the depth, which is in line with Navico/B&G's claims. There's a learning curve, as with radar, in interpreting the visual representations, and the "data points" display is what I prefer.

Creeping up on a reef gap and finding coral heads or sunken debris is what this is for, because if you are in, say, 20 feet of depth, how fast can you be going before you reel off 100 feet or so foward? Doing seven knots on a fresh day in the ocean would give very little reaction time, so this is a "nice to have" technology, rather than an excuse not to keep a watch.

On the other hand, with a cat, you can go where others cannot, but if you put a 20 cm. offset on the "shallow" alarm, I can see the utility for anchoring in appropriate weather in some otherwise tight spots. But if you are blasting at 12-16 knots and a whale is snoozing ahead? Not so much!


I go into more depth, pun intended, in this blog post: https://alchemy2009.blogspot.com/201...teresting.html
__________________
Can't sleep? Read www.alchemy2009.blogspot.com for fast relief. Can't read? Avoid www.volumesofsalt.blogspot.com, because it's just personal reviews of sea books.
S/V Alchemy is offline   Reply With Quote
Old 15-10-2018, 12:57   #8
Registered User
 
CatNewBee's Avatar

Join Date: Aug 2017
Boat: Lagoon 400S2
Posts: 1,393
Re: Forwardscan cats and whales

It is more of 60..75 degree than 45, so you look approx. 2-3 times the depth ahead. in very shallow water quite useless, but you can see steep underground ahead quite well. On a depth of 18m you may look forward up to 36m (3 boat length). Nothing for high speed. I turn it on when aproaching anchorages or marinas on my second display.

I think it gives some peace of mind, but it is not meant for whales or logs.

I have the B&G forward scan system with vulcan 7 display along with a 'free' C-Map of the eastern Med. I prefer the Navionics charts. Another disadvantage is that the vulkan displays have their sd card slot on the back. If you mount it in the navstation you must disassemble it to change the charts.

I use it therefore merely as a sailsteer and data display, and for the forward scan, and use my 12 inch Raymarine chartplotter with Navionics for navigation.

But it is a nice backup display so.
CatNewBee is offline   Reply With Quote
Old 15-10-2018, 14:35   #9
Registered User

Join Date: May 2016
Location: Brisbane Qld Australia
Boat: Oram 39C 39.98 m
Posts: 16
Re: Forwardscan cats and whales

Ok very informative thank you all. Really helps to get my brain around the practical use of this tech. Sounding like Radar is a far better bet when traveling at night.
moreton99 is offline   Reply With Quote
Old 15-10-2018, 14:58   #10
Registered User

Join Date: Jan 2014
Location: Sydney, NSW
Boat: FreeFlow 50 cat
Posts: 928
Re: Forwardscan cats and whales

That's a thought. I wonder if radar on the "rain" setting will pick up the spout of a whale just in front of you at night?

Just kidding...
BigBeakie is offline   Reply With Quote
Old 15-10-2018, 15:00   #11
Registered User
 
CatNewBee's Avatar

Join Date: Aug 2017
Boat: Lagoon 400S2
Posts: 1,393
Re: Forwardscan cats and whales

Quote:
Originally Posted by BigBeakie View Post
That's a thought. I wonder if radar on the "rain" setting will pick up the spout of a whale just in front of you at night?

Just kidding...
it depends how high the whale flies
CatNewBee is offline   Reply With Quote
Old 15-10-2018, 15:05   #12
Registered User

Join Date: Jan 2014
Location: Sydney, NSW
Boat: FreeFlow 50 cat
Posts: 928
Re: Forwardscan cats and whales

True, but that's a breach, i.e. when they "jump" out of the water. I was meaning when they exhale, a big spray of water goes up. The new Quantum 2 radar is really sensitive picking up close objects, so I was just musing....
BigBeakie is offline   Reply With Quote
Old 16-10-2018, 00:31   #13
Registered User

Join Date: Jul 2014
Location: Hawaii
Boat: Jeanneau SO DS 49
Posts: 99
Re: Forwardscan cats and whales

I’ve hit whales 3x. Twice while sailing, once while motoring. Sonar has a short range but will give you a warning if you are watching it or if the alarm goes of. Still even with instant reactions the chance of stopping before contact is slim. Whales can hear well, therefore a noise generator (deaf leopard) is a wise choice. But no guarantees as I hit a humpback going 5 knots. I hope science can find a frequency that we can transmit for best results.
SteveSadler is offline   Reply With Quote
Old 16-10-2018, 01:25   #14
Registered User
 
CatNewBee's Avatar

Join Date: Aug 2017
Boat: Lagoon 400S2
Posts: 1,393
Re: Forwardscan cats and whales

Whales communicate at very low frequencies, they barely hear the sonar. Also they are quite big species and do not really fear other animals, so I doubt they will be scared off of Meatfoaf music at all, nor will they give way to a recreation boat. You can install a marine sonar like the ones in submarines to listen to the whales instead and try to avoid them.

But there are also other floating objects out there you may hit, that do not produce any sound, nor get scared by your music.
CatNewBee is offline   Reply With Quote
Old 16-10-2018, 01:48   #15
Registered User

Join Date: Sep 2014
Location: Ballina, NSW, Australia
Boat: Schionning,Wilderness Catamaran, 11.00m
Posts: 4
Re: Forwardscan cats and whales

Quote:
Originally Posted by moreton99 View Post
I was thinking that the forward sounder pulses might help let the whales know where we are?

Whilst not a hater of Meatloaf it might wear a bit thin over and over on an overnight passage.
Hi I hit a whale off Currumbin, Gold Coast @ 0230 last year sailing south, I think it must have been dozing just below the surface, gave us a hell of a scare. Minor damage to the rubber but threaded 3 bolts on my sail drive still able to get to Ballina and cross the bar. See plenty of whales on my trips up and down the coast getting worse every year.
A cruiser told me to keep the depth sounder on around whale time the ping from the sounder gives them a warning, I can say it works as i've seen a pod ahead they disappear about 50m or so away and re surface behind me, which I think gives this theory some credence.
__________________

clarkey is offline   Reply With Quote
Reply

Tags
dsc

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Does the B&G Forwardscan provide DEPTH data? phantomracer Marine Electronics 2 10-09-2018 18:25
Depth Finder Refit...is Forwardscan worth it? WindJunkie Construction, Maintenance & Refit 2 01-05-2016 03:06
CHIRP vs ForwardScan hanslamitraille Marine Electronics 4 22-11-2015 22:46
Bottom Paint Color and Whales jsoceanlord General Sailing Forum 27 21-08-2010 12:19
the FAITHFUL Dances with Whales... bradbarrett General Sailing Forum 4 14-10-2003 20:16



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 16:44.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.