SailNet Community

SailNet Community (http://www.sailnet.com/forums/)
-   Electronics (http://www.sailnet.com/forums/electronics/)
-   -   Radar and AIS (http://www.sailnet.com/forums/electronics/121273-radar-ais.html)

newhaul 02-04-2014 08:55 PM

Re: Voyaging on $500 per month
 
I have prepaid cell and even with unlimited everything only fifty includes internet on phone and don't know initial cost of ais unit but once installed only expense would be what's spent to generate the power to recharge batteries they are available for 12 volt installations

tdw 02-04-2014 09:52 PM

Re: Voyaging on $500 per month
 
I realise this will vary depending on where you sail but I'd much rather have a Chart plotter that is AIS enabled than Radar.

travlineasy 02-04-2014 10:24 PM

Re: Voyaging on $500 per month
 
Gotta agree with you on that Fuzzy - Radar is nice, but the AIS system can be a real live saver. However, I would rather have both 3G radar and AIS on the plotter. I came real close to smacking some offshore rigging one night, and almost nailed a huge stake net in Chesapeake Bay off Tilghman Island, one that wasn't on the charts and two miles from shore. Got my attention, and AIS would have provided no benefit at all.

As for the guy trapped in poverty, that's crapola as far as I'm concerned. At age 50, he either doesn't want to work, or he something wrong upstairs. There are loads of jobs out there that pay pretty darned well, and they frequently go wanting because no one seems to want to start at the bottom and work their way up these days. "Yeah, I'll take the job if you make me chairman of the board." seems to be today's attitude. He could drive a garbage truck and make $45,000 a year in most medium sized cities, plus a retirement and benefit plan. Bet if you asked if he would mind driving a garbage truck he would look at you like you had three heads.

Gary :cool:

Lou452 02-04-2014 11:00 PM

Re: Voyaging on $500 per month
 
Quote:

Originally Posted by tdw (Post 1380793)
I realise this will vary depending on where you sail but I'd much rather have a Chart plotter that is AIS enabled than Radar.

I think a lot of technical parts of sailing will change. Navigation and the decisions about what systems will be the safe and cost effective are going to be a challenge for me to budget.
This would be a good place to go navigation on a budget :)
Good day, Lou

aeventyr60 02-04-2014 11:22 PM

Re: Voyaging on $500 per month
 
Quote:

Originally Posted by tdw (Post 1380793)
I realise this will vary depending on where you sail but I'd much rather have a Chart plotter that is AIS enabled than Radar.

TDW-You'll think twice or more on this sailing through Indonesia.....

Lou452 02-04-2014 11:38 PM

Re: Voyaging on $500 per month
 
Quote:

Originally Posted by aeventyr60 (Post 1381057)
TDW-You'll think twice or more on this sailing through Indonesia.....

Ok expand on this. What size ship will have AIS ? What size craft is to small for radar ? They say sailboats will not show on radar without enhancement? What kind of collision is the most likely?
I ask with no real experience so you will have to give both sides of the story.
Thanks, Lou

svzephyr44 02-05-2014 06:54 AM

Re: Voyaging on $500 per month
 
Quote:

Originally Posted by Lou452 (Post 1381097)
Ok expand on this. What size ship will have AIS ? What size craft is to small for radar ? They say sailboats will not show on radar without enhancement? What kind of collision is the most likely?
I ask with no real experience so you will have to give both sides of the story.
Thanks, Lou

I said I would not post again on this thread. I recant only to provide information on AIS.

Who has to carry: Automatic Identification Systems (AIS)

1. In general big ships. In Singapore everyone by law - something that is likely to become more prevalent in very crowded maritime areas. One of the exemptions - fishing boats - sometimes a problem when making coastwise passages. Fishing boats tend to be brightly lit so they are pretty easy to see unless the weather is bad. I think that you will see the rest of the major maritime world moving toward the Singapore rule - you must have a transmit type AIS to cruise in their waters. This will be led by the harbors that already require all ships to report in when entering and leaving port (VTS Systems - see here:
2. Sailboats are hard to see on most radars - including both commercial and recreational radars. If you call another vessel on the VHF they can usually figure out where you are but are not likely to see you on the radar before you call. The bridge watches are not staring at the radar and the alarms typically will not be set to go off for a return that small. Radar reflectors help a little, but not all that much. One thing that surprised me: back in the days of paper charts if you gave a ship your lat and long they could pretty much pinpoint your location in a couple of seconds. Now with the glass bridges it seems to take a lot longer. I am not sure exactly why this is true.

3. What kind of collision is most likely? The one where you are not in the cockpit looking around to see who can hit you. Even with an AIS transmitter you are not complexly safe from large ships. I have been run down twice, once by a cargo ship, once by a Carnival Cruise Liner. In both cases my AIS was blipping away. CCL Captains have a very bad reputation in the shipping world. They seem to think that the rules of the road are they go where they want and everyone else gets out of the way. :mad: (actually I have been run down three times - in the pre-AIS days I was hit by a "laker" off Alpina in bad rain and fog. Did a mess to the bow of the boat but we stayed afloat and made it into a safe harbor.)

Fog banks can be deadly. I was approaching the Blue Water bridge at the foot of Lake Huron. There was a big fog bank under the bridge. The rest of Lake Huron was clear as a bell. My radar painted a huge target - I thought the bridge of course. All of a sudden a huge laker (they look even bigger from 100 feet looking up at the bow coming right at you!) came out of the fog bank heading directly at me. Five shorts on my pathetic little horn, right emergency rudder, all ahead flank, I got out of the way (barely.) They never saw me until I was abaft the wheelhouse tooting my little horn. Then they hit their fog horn. Darn near blew me out of the water! (I guess this counts for run down #4) They never slowed or turned. Would not have mattered anyway unless they needed to pick up the pieces. They just can't maneuver that quickly. (This was, btw, in my pre-AIS days.) Another minute and I was out of the fog in the St. Clair river.

Slightly off topic but your deck navigation lights on a typical sailboat are not worth much either. Offshore your lights tend to be obscured by wave action. The exception is a tricolor. Most commercial ships are illuminated at night. They are pretty easy to see. The exception is ships carrying explosive material such as oil. They usually have a minimum of lights visible - just the required navigation lights. I always wondered how the bridge watch on a brightly lit ship could see at night. We could track ships visually 10 NM away. We would chat with the bridge crew and they would know where we were (we have transmit AIS) but could not see us visually unless they got less than 1 NM away. That is why I now have a tricolor 60 feet up on top of the mast. In general on the open ocean 1 NM was the courtesy separation - large ships would alter course to give us a CPA of 1 NM or more. An aside: When I first started cruising I was confused by the side lights on big ships. In the recreational world the "bow lights" are the red and green lights located near the bow. But the COLREGS require side lights, not "bow lights." Most commercial ships have the side lights on the house in the stern. I was looking at a colored light thinking I was looking at the bow when in fact I was looking at the stern. Everyone seemed to be steaming in reverse...


Should you cruise in US waters (elsewhere in the world too, my experience is off Norfolk) in places like VACAPES you will discover that United States Navy ships don't transmit on AIS. And they don't show up on radar. And they don't have a lot of lights on. In fact you will swear they are not there until your radio crackles and they talk to you!! Even then you will swear they are not there. And they only talk to you if they want you to do something. Otherwise they just ghost by. A good thing from a combat standpoint, a little scary when sailing. The military operating areas are marked on the charts but they do have to get to them and get back home.

aeventyr60 02-05-2014 07:59 AM

Re: Voyaging on $500 per month
 
Quote:

Originally Posted by Lou452 (Post 1381097)
Ok expand on this. What size ship will have AIS ? What size craft is to small for radar ? They say sailboats will not show on radar without enhancement? What kind of collision is the most likely?
I ask with no real experience so you will have to give both sides of the story.
Thanks, Lou

Ok, so it's around 5 PM local time in Indo waters, maybe doing your before dark checks, scanning the horizon, etc, maybe putting in a reef, having a bite to eat, scannng the horizon 360 degrees with the MKII eyeball, AIS, etc, Noting to be seen, great, nice night ahead. About an hour later it's dark...Then...WOW...as far as your eye can see are lights...dim, kinda dim. maybe bright, white, yellow, green, red, blue, flashing occulting, every kind of flicker...what's this? geez, it's a zillion small craft, bobbing in the swell fishing, not a proper nav light in the mix...jeez, talk about a terrorist activity...no rhyme or reason to direction, some boats with no lights, they flick a Bic lighter as you go by...we shine the zillion power light on the sails to increase our visibility...so yeah, not a fun night...and this occured on many nights. Radar helped, AIS was worthless here. MKII eyeball price less!

aeventyr60 02-05-2014 08:10 AM

Re: Voyaging on $500 per month
 
Quote:

Originally Posted by svzephyr44 (Post 1381377)
I said I would not post again on this thread. I recant only to provide information on AIS.

Who has to carry: Automatic Identification Systems (AIS)

1. In general big ships. In Singapore everyone by law - something that is likely to become more prevalent in very crowded maritime areas. One of the exemptions - fishing boats - sometimes a problem when making coastwise passages. Fishing boats tend to be brightly lit so they are pretty easy to see unless the weather is bad. I think that you will see the rest of the major maritime world moving toward the Singapore rule - you must have a transmit type AIS to cruise in their waters. This will be led by the harbors that already require all ships to report in when entering and leaving port (VTS Systems - see here: Vessel traffic service - Wikipedia, the free encyclopedia

2. Sailboats are hard to see on most radars - including both commercial and recreational radars. If you call another vessel on the VHF they can usually figure out where you are but are not likely to see you on the radar before you call. The bridge watches are not staring at the radar and the alarms typically will not be set to go off for a return that small. Radar reflectors help a little, but not all that much. One thing that surprised me: back in the days of paper charts if you gave a ship your lat and long they could pretty much pinpoint your location in a couple of seconds. Now with the glass bridges it seems to take a lot longer. I am not sure exactly why this is true.

3. What kind of collision is most likely? The one where you are not in the cockpit looking around to see who can hit you. Even with an AIS transmitter you are not complexly safe from large ships. I have been run down twice, once by a cargo ship, once by a Carnival Cruise Liner. In both cases my AIS was blipping away. CCL Captains have a very bad reputation in the shipping world. They seem to think that the rules of the road are they go where they want and everyone else gets out of the way. :mad: (actually I have been run down three times - in the pre-AIS days I was hit by a "laker" off Alpina in bad rain and fog. Did a mess to the bow of the boat but we stayed afloat and made it into a safe harbor.)

Fog banks can be deadly. I was approaching the Blue Water bridge at the foot of Lake Huron. There was a big fog bank under the bridge. The rest of Lake Huron was clear as a bell. My radar painted a huge target - I thought the bridge of course. All of a sudden a huge laker (they look even bigger from 100 feet looking up at the bow coming right at you!) came out of the fog bank heading directly at me. Five shorts on my pathetic little horn, right emergency rudder, all ahead flank, I got out of the way (barely.) They never saw me until I was abaft the wheelhouse tooting my little horn. Then they hit their fog horn. Darn near blew me out of the water! (I guess this counts for run down #4) They never slowed or turned. Would not have mattered anyway unless they needed to pick up the pieces. They just can't maneuver that quickly. (This was, btw, in my pre-AIS days.) Another minute and I was out of the fog in the St. Clair river.

Slightly off topic but your deck navigation lights on a typical sailboat are not worth much either. Offshore your lights tend to be obscured by wave action. The exception is a tricolor. Most commercial ships are illuminated at night. They are pretty easy to see. The exception is ships carrying explosive material such as oil. They usually have a minimum of lights visible - just the required navigation lights. I always wondered how the bridge watch on a brightly lit ship could see at night. We could track ships visually 10 NM away. We would chat with the bridge crew and they would know where we were (we have transmit AIS) but could not see us visually unless they got less than 1 NM away. That is why I now have a tricolor 60 feet up on top of the mast. In general on the open ocean 1 NM was the courtesy separation - large ships would alter course to give us a CPA of 1 NM or more. An aside: When I first started cruising I was confused by the side lights on big ships. In the recreational world the "bow lights" are the red and green lights located near the bow. But the COLREGS require side lights, not "bow lights." Most commercial ships have the side lights on the house in the stern. I was looking at a colored light thinking I was looking at the bow when in fact I was looking at the stern. Everyone seemed to be steaming in reverse...

Should you cruise in US waters (elsewhere in the world too, my experience is off Norfolk) in places like VACAPES you will discover that United States Navy ships don't transmit on AIS. And they don't show up on radar. And they don't have a lot of lights on. In fact you will swear they are not there until your radio crackles and they talk to you!! Even then you will swear they are not there. And they only talk to you if they want you to do something. Otherwise they just ghost by. A good thing from a combat standpoint, a little scary when sailing. The military operating areas are marked on the charts but they do have to get to them and get back home.

Good info. However, Singapore waters are really small. We sail just outside the Singapore Harbor limits and most often test the line, Patrol boats every kilometer or so, keep all transgressors out. AIS not required for us to Enter either. The Mallaca strait and Singapore Straitts s have a VTS-Vessel Traffic sepration zone, so all the big boys keep to the lanes...however, out of Port Klang (Malaysia water) Tugs with tows and no lights seem to operate with impunity and without AIS. Most of the trawlers, squid boats and other fishing boats/craft don't use it either. This we found to be the case in Thailand, Malaysia, Borneo and the Philippines. So, a lot of work here to do in getting AIS adopted by the Maritime/fishing industry. Proper watch ON Deck still the best way to stay out of trouble. Sharpen up those MKII eyeballs....

svzephyr44 02-05-2014 08:16 AM

Re: Voyaging on $500 per month
 
Quote:

Originally Posted by newhaul (Post 1380553)
Don't know initial cost of ais unit but once installed only expense would be what's spent to generate the power to recharge batteries they are available for 12 volt installations

VHF Radio with AIS (receive only with built in display) about cheapest $250 US

AIS transmit/receive transponder cheapest $550 US. Requires an antenna (can share with your VHF antenna) and a display. Baseline cheap laptop maybe $400 US, baseline chart plotter maybe $1,000 US.
AIS units do transmit frequently so they do provide a load for the batteries but the load is inconsequential compared to the load from a laptop or chart plotter.

I expect that someone will come out with an integrated transmit/receive AIS in the very near future. I expect they already exist and are only waiting on FCC approval.


All times are GMT -4. The time now is 05:27 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012