Sailors rescued
- Thread starter rgranger
- Start date
Sorry for the link to another forum... but someone posted screen-shots of the write-up from the owner, 1st hand account of what happened... interesting to read.
Post 5 to 10
Post 5 to 10
Wow, what a well-written account for once. Usually, these stories don't have any vital information. Feel extremely bad for the owner and crew of that boat. It just goes to show that even the best crew can't avoid a random disaster when it comes along. They seemed to handle it in the best way possible and it shows how necessary it is to be prepared (and calm)!
Amazing story, with a good (as possible) ending. They were well prepared that resulted in a quick and satisfactory recovery. Amazing that they were rescued in less than ten hours in the middle of the Pacific. Feel for the captain losing his boat; hopefully it was insured.
I am interested in the technology the EPRIB/PLB broadcasts your GPS at the moment you push the button after that I believe it puts out 121 MHZ for a radio direction finder equipped searcher. But in this case another yacht picked them up 10 hours later. Is somebody estimating current and wind drift from the initial fix and updating the searchers? If the searchers get within a few miles then flares or a handheld radio could pull them in.
EPIRBs use 406 MHz COSPAS/SARSAT satellite communications which includes your GPS position information, the 406 MHz transmission burst goes out approximately every 52 seconds and generally updates GPS position information with each burst. They also use 121.5 MHz homing beacons for the search and rescue crew to home in on, the 121.5 MHz signal is continuous (with brief interruption during 406 MHz transmission). The C/S system uses LEO, GEO and now MEO satellites. The location of the EPIRB can also be determined by the LEO and MEO receiving satellites even without GPS information being encoded in the signal. The C/S system does have models for drift so once the 406 MHz signal stops they can predict location. The 406 MHz satellite signal is active for 24 hours after the transmission is initiated. The 121.5 MHz homing beacon will run for as long as the battery holds out but is supposed to last 48 hours at least (I believe this duration is accurate, I work on aircraft ELTs and the maritime EPIRBS may be different, some homing beacons have a 150 hour requirement).
He mentions a personal beacon, probably a PLB, with AIS. This would broadcast his location over VHF so any vessel close by would directly receive his location and can find him quicker. The rescue boat was a recreational boat (like all of us) so likely doesn't have 121.5 MHz RDF on board and the PLB AIS would be much more useful.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 23,259
Suspect the rescue boat was equipped with SSB which is used on open ocean to communicate. Once close you have to search. It is fortunate for them that the Pacific was placid.
VHF is line of sight. It is a big ocean.
VHF is line of sight. It is a big ocean.
If you read the first-hand account, it explains that there were boats nearby because of an ARC trans-pac rally, and that they communicated via Starlink and VHF. They were thus able to be rescued quite quickly. Their EPIRB worked, but the coordinating station in Peru didn't need to have a large ship divert because the other boats were closer and already in contact with the crew in their raft.
From what Ive read, the rescue boat (a Leopard 45 “Rolling Stone”) was using Starlink for communication (WhatsApp). Apparently the initial coordinates were relayed from a boat the mishap crew called (via Iridium Go) just after abandoning ship. When the mishap crew saw the lights from the Leopard they called them on VHF and activated the PLB AIS.