Sea-me or AIS transponder?

Fascadale

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Is there any point in having a Sea-me if I fit an AIS transponder ?

AIS receiver about £200
Dual band Sea-me about £700
AIS transponder and receiver about £500

Radar is not an option.
I have an Echomax radar reflector
 

RobbieW

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Depends where you go. I expect there are lots of small and medium sized fishing and other commercial boats that have radar but not an AIS reciever. In fog they'd be looking at their radar displays.

I'd have the dual-band RTE.

+1 thats where my budget went in the choice between RTE or AIS transponder - the boat already had an AIS recieve engine.

The bulk of 300 gt+ commercial traffic is still more likely to be using RADAR as thier primary collision avoidance tool for the next few years. They are not required to use an integrated navigation system and are likely to have the minimal AIS installation required, ie, standalone textual. One risk of an RTE, even dual band, starts to become craft fitted with 'broadband' RADAR as it is my understanding that they dont transmit on the same frequencies as X or S band sets. Thus the transmissions are not returned by the RTE.
 
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SHUG

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Sea Me gives out a strong return signal which registers on big ship (and small ship) anti- collision systems. This means that they will be obliged to take avoiding action if you have right of way. AIS will merely identify the ship that hit you because there was an inadequate radar return from your vessel.
OK that's a bit extreme but the best option if you are sailing regularly in shipping lanes is the have the lot...AIS,SeaMe and radar.
 

Coaster

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A couple of years ago DHM Southampton provided some pretty sage advice to members of the Yately Offshore Sailing Club.

http://www.yosc.org.uk/html/announcements.html#navigationaids

The advice remains valid.

Thanks for the link. I was particularly struck by the comment that the RTE signal cannot be filtered out, which must be an overwhelming argument for putting that system first, before an AIS transponder, in the hierarchy of safety equipment.
 

Juniperskip

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AIS is a significant source of data for you but questions remain on the wider use of the equipment to "avoid" you, therefore the pririty remains, in my view, to make yourself as big a target as poss. I would opt for a dual band Seame and a low cost AIS receiver. The latter gives you the info to call a vessel you are concerned about to discover their intentions and whether they hold you without the inevitable "vessel on my ......" call which a lot of watchkeepers will ignore.
 

stuartwineberg

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Another vote for Sea Me

We recently had a tour of the Solent coastguard. After I got over the shock of realising that they don't have radar cover across the Channel, it was very informative. The bloke said - repeatedly, that he advised an AIS receiver so you can identify and radio oncoming shipping and a Sea-Me device to be "seen" on radar.
 

bbg

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We recently had a tour of the Solent coastguard. After I got over the shock of realising that they don't have radar cover across the Channel, it was very informative. The bloke said - repeatedly, that he advised an AIS receiver so you can identify and radio oncoming shipping and a Sea-Me device to be "seen" on radar.
That's my view as well. I had occasion to call a ship off Land's End a few days ago, when the AIS showed a CPA of 0.1 nm.
When offshore I'll keep the Sea-Me and AIS receiver on all the time, and just put the AIS in "send" mode on the rare occasions I think it would potentially be useful (e.g. when near a TSS).
 

Barry Jones

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Talking about Broadband radar.

I believe they DO use the same frequencies as a magnetron equipped radar.

The problem is that the peak output power is a lot lower due to the nature of the technology.
 
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BlueSkyNick

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We recently had a tour of the Solent coastguard. After I got over the shock of realising that they don't have radar cover across the Channel, it was very informative. The bloke said - repeatedly, that he advised an AIS receiver so you can identify and radio oncoming shipping and a Sea-Me device to be "seen" on radar.

The CG dont understand the difference between the theory and the practice, then. I took avoiding action whilst sailing across the channel, on the starboard bow of a ship. Afterwards, I tried two calls using MMSI from the number picked up on AIS, both cancelled, and twice on Channel 16, both ignored.

As Graham of these forums explained to me, you have to assume the watch officer is a Liberian coke addict who is having a kip.
 

Tranona

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As Graham of these forums explained to me, you have to assume the watch officer is a Liberian coke addict who is having a kip.

So, the priority is knowing the ship is there and keeping well out of the way. Basic instinct, helped hugely by having an AIS receiver in addition to eyeball. . Maybe not a lot of point in sending out your own signal if nobody is watching (which of course is not the case most of the time).
 

BlueSkyNick

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Fully agree.

In fairness, another time I helped a boat in fog who had no radar or AIS by advising ships' names as they were coming up the channel. One extra very large Maersk ship was very communicative and helpful, by saying he could see both of us on radar and would pass 1nm ahead.... which he did at 20knots!
 

Ex-SolentBoy

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The forums are frequented with questions like this.

Radar or AIS?
AIS or Seame?
Seame or AIS?
Radar reflectors or some other stuff?

The bottom line is this:-

1. Some items help others see you so they can avoid you. This only works if they have the right equipment to do so, and therefore cannot be relied upon. Anything like this must be on the "nice to have list"

2. Some things help you see other stuff so you can avoid it. These are the priorities. Forever the collisions regs. Just make sure you don't hit anything.

If you can't work out which item falls into which category you are wasting your money on whatever you buy.
 

Barry Jones

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I know quite a lot of watch officers and they are usually overworked guys burdened with excessive paperwork by the bureaucracy that goes hand-in-hand with modern shipping these days.

Many ships are dry and drugs tests are not uncommon.

I have noticed a reluctance to engage yachts in VHF traffic and a few that admit to ignoring calls received from yachts in open waters.

http://www.dft.gov.uk/mca/mgn_324.pdf

As Graham of these forums explained to me, you have to assume the watch officer is a Liberian coke addict who is having a kip.
 

snooks

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I have radar, so I know where everything is out there. This helps me navigate and avoid a hitting or being hit and lets me take control of my destiny.
I have AIS (receiver only) so I can identify anything big and ship shape that is heading for me, this helps me avoid being hit.
I have an RTE, this helps me be seen at day or night, but only by people with a radar who look at it. It's more visible than nav lights, and the best way of being seen by shipping at night or in fog.

My primary collision avoidance technique is to see them, identify which way they are going and take positive action early on rather than expect someone else to see me.

AIS range is 20 miles, radar range 8-10, anything big and fast shows up on AIS, anything small and slow shows up on radar.

In restricted vis anyone with radar on board is usually using it as their primary navigation aid, and if I'm returning a larger echo than the size of my yacht, it's no bad thing. :D
 

differentroads

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An old thread, I know, but it comes up first in a Google search, so here's my experience on the topic.
Offbeat has an old single band See-Me RTE, a Vesper AIS receiver and an Icom DSC radio. Sailing with this kit in the southern North Sea, the English Channel and now across Biscay and down to Lisbon, I've evolved this routine: use eyes and the AIS on 12 mile range setting (AIS, that is, I dont have bionic eyes) to identify vessels that pose a collision risk; when 3 to 5 miles away call them up on the VHF and tell them my intentions (usually turning to avoid them even if I should be the stand on vessel); ask them to confirm that they will maintain their course. On all occasions but one, the watch officer has replied quickly and professionally, confirming that they have me on radar and often quoting the cpa to me. Even that Yemeni coke fiend was right on the ball - very chatty in fact (irony - read the earlier posts in case anyone has a sense of humour failure).

I'm considering upgrading to the dual band See-Me as I plan ocean passages from next year. And I ought to work out how to get my AIS to send mmsi to my VHF; but this system has worked well for us in good vis, thick fog and at night.

If I had enough money I'd add radar in order to see small fishing vessels, land and squalls. btw, most (If not all) modest to large sized fishing vessels so far have had AIS fitted and switched on.
 
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