EPIRB or PLB info direct to boat?

[johnandtessa]

As soon as they were approved in the US, we bought 4 Kannad Safelink AIS personal AIS beacons and they are AWESOME. Our race crew wears them at night or when rough and our kids wear them whenever on deck and not flat calm. They are tiny and when deployed instanty appear on our plotters and AIS screen. They have a 7-year battery and are very easy to deploy. Can be auto-deployed but we have not used that option.
John - Tenho

[RUSTYNAIL]

A couple of answers to above comments: For sure the gps isn't instantaneous, but very close depending on the PLB/EPIRB's antenna position and deployment. Many activated beacons have the gps position shown on the first 406 burst/transmission to the geosynchronous satellite after a very brief warm up time. The small gps antenna in the beacon needs a clear look at the gps satellites. The strong transmitted 5 watt 406 signal can blow through the vessel's hull sometimes when the gps signal coming in is too weak for the beacon to pick up the incoming gps signals. Some of the older gps receivers in EPIRBs were slow.

Getting other countries on line with new 406 MHz DF equipment is just a matter of educating the governments. Eventually the saving of people quickler with the long range 406 DF capability will soon be well known. Not only is 406 DF capability much better than 121.5 DF'ing, with some 406 DF receivers, the pilots can read the beacon's hexidecimal code, and receive the transmitted 406 signal's gps position right in their cockpit. Local city/county SAR units will take some time to get this new technology, as retrofitting or upgrading isn't cheap. Once all of the older non gps 406 beacons are phased out, the RCC's will be able to get the gps position to the local rescue units that don't have 406 DF or 121.5 DF capability.
Standing by, Greg

[RUSTYNAIL]

Johnandtessa

Does your AIS receiver/plotter sound an alarm when the safelink is activated?

[johnandtessa]

Rusty Nail is probably right in everything he wrote but all I know is that if someone goes overboard at night in 5 meter seas while under sail nothing but an AIS/direction PLB is going to save them. And, no one else is going to help. The Kannads are really fast and a revolution in saving a life at sea

[RUSTYNAIL]

Johnandtessa,
I'm 100% behind the AIS unit and quick alerts and locating a MOB. I'm still curious about getting the correct AIS receiver so it will wake up someone sleeping before the boat gets too far away, in case the guy looking at the plotter was the one that went overboard.
Greg

[RUSTYNAIL]

From my experience, Australia is ahead of the curve, and I wouldn't argue with any idea an Aussie has because their boaters immediately sail in serious waters, nothing like our waters where most of the recreational boating happens.

[xymotic]

Originally Posted by RUSTYNAIL

Johnandtessa,
I'm 100% behind the AIS unit and quick alerts and locating a MOB. I'm still curious about getting the correct AIS receiver so it will wake up someone sleeping before the boat gets too far away, in case the guy looking at the plotter was the one that went overboard.
Greg

I don't think ANY ais black-box units do anything with the data. So really you need to make sure that your PLOTTER understands the AIS-SART sentence and starts alarming acordingly.

edit: just found this cool device
http://www.wamblee.it/eng/W440.html

[johnandtessa]

Greg - As for hooking the Kannads up to activate a MOB alarm, I am not sure. Since they basically appear as another vessel when activated, it might work to simply set the basic AIS vessel alarm to 1/4 mile or so. We have a 4 day crossing coming up next week and I will experiment around a little then. John

[goboatingnow]

Originally Posted by johnandtessa

Greg - As for hooking the Kannads up to activate a MOB alarm, I am not sure. Since they basically appear as another vessel when activated, it might work to simply set the basic AIS vessel alarm to 1/4 mile or so. We have a 4 day crossing coming up next week and I will experiment around a little then. John

most of the plotter manufacturers have updated their software to correctly display AIS SART locations as a MOB rather the a ship..

Dave

[RUSTYNAIL]

John, I recently retired from the coast guard after 43 years, and I had a lot to do with safety equipment, EPIRBs and testing AIS in beacons. I am more than a curious boater, and appreciate any feedback. I sail a lot and like to stay alive. This is a powerful forum and lots of great ideas and experience is shared. Thanks,
Greg

[Paul Elliott]

Originally Posted by johnandtessa

Greg - As for hooking the Kannads up to activate a MOB alarm, I am not sure. Since they basically appear as another vessel when activated, it might work to simply set the basic AIS vessel alarm to 1/4 mile or so. We have a 4 day crossing coming up next week and I will experiment around a little then. John

You should probably set the range alarm to at least one mile. After falling overboard, it's going to take some time for the MOB to get oriented and then trigger the Kannad AIS/GPS alarm (say one minute). It then takes minute or two for the alarm to acquire and transmit the GPS position. Say that adds up to three minutes. If you are sailing at 8 kts, in three minutes you will have traveled 0.4 miles. Position updates are sent once a minute, so if your receiver misses the first transmission the MOB is even farther away.

With a one-mile guard zone, you may have quite a few nuisance alarms, which means you will probably be turning the alarm off (depending on where you are sailing).

The first transmission from the Kannad unit occurs within 15 seconds of activation, but this first transmission does not include the GPS position. If your chartplotter (or whatever) has not been updated to recognize this first transmission (AIS message #14, "SART ") as coming from a SART, then it won't trigger an alarm. (SART = Search And Rescue Transmitter) Subsequent transmissions are AIS message #1, which carry the GPS position.