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Yeah, after listening to that, I'm skeptical...
not good
- Thread starter getakey
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Yeah, after listening to that, I'm skeptical...
The CG has suspended the Search. Have not yet labelled a hoax, but sure seems that way
So if it was a hoax,the person that did it was on a boat since CG had positioned it 65 miles off shore based on radio signal. Based on the sea conditions that day, most likely not some smaller boat that ran out there quickly. Hard to believe some serious Cruiser that is travelling up/down coast would do this.
So, someone travels 65+ miles out and back to pull off this hoax? Very likely a 10+ hour trip in those conditions
So if it was a hoax,the person that did it was on a boat since CG had positioned it 65 miles off shore based on radio signal. Based on the sea conditions that day, most likely not some smaller boat that ran out there quickly. Hard to believe some serious Cruiser that is travelling up/down coast would do this.
So, someone travels 65+ miles out and back to pull off this hoax? Very likely a 10+ hour trip in those conditions
CG said it was calculated from radio signal - one report I heard said recvd by 1 tower. They also mentioned boat radar in 1 article - not sure what that was about.
"The Coast Guard was able to pinpoint the area where the boat allegedly went down because it has a new radio program, called Rescue 21, which gives it a cleaner line of bearing from radio messages, making it easier for the Guard to locate mariners in distress, McKenzie said. That put the sailboat at 65 miles off the coast of Monterey, about 100 miles south of San Francisco, in the open ocean."
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That's what I'm wondering - was this a single LOB or an intersection of several? If it only hit one RFF tower, I think the media interpreted things a bit liberally in terms of positioning. With a single tower, it would be VERY tough to tell whether it was 65 miles or 65 feet from the RFF.
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Precisely. A DF fix from one tower is a line of position. There can be an interpretation by the operator of signal strength vs distance from the tower but that would be based upon a known transmission power. If a weak hand held was tranmitting it could be misinterpreted as a distance fixed unit. That is what makes me suspicious.
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Cellphone coverage seems unlikely if they were actually 65 miles offshore. As for whether or not the GPS will function without service available, I don't know.
There was no mention of cell phone. They specifically cited this new "Rescue 21" system.Don't know if the media misinterpreted what the CG said about the position or not. Every report I saw stated pretty much the same thing.
Here's some info on Rescue 21
http://en.wikipedia.org/wiki/Rescue_21
I know 1 cell tower can compute location from cell radio signal. The tower is an array and computes direction by time difference from signal received in the different parts of the array. Its not nearly as accurate as gps, but still provides a location.
Perhaps Rescue 21 uses similar technology
My understanding is that distance can be estimated with 1 tower as well. Not very accurate, but can give a general location which includes estimated distance and bearing. Much better accuracy when 2 towers involved.
That said, we don't know how many towers were involved in the CG calc. I heard a report say 1 tower, but did not see it documented
did a quick read on Rescue 21. It does require 2 towers to calc distance.
My question is how can they pick up a VHF signal from 65 miles out?
If the antenna was at the top of the mast and the receiver was located on one of the coastal mountains (which I think they are in califironia, I could see the transmission getting through. No problem reaching the Marine operator from Catalina 25 miles out because the receiving towers are up high.
My question is how can they pick up a VHF signal from 65 miles out?
If the antenna was at the top of the mast and the receiver was located on one of the coastal mountains (which I think they are in califironia, I could see the transmission getting through. No problem reaching the Marine operator from Catalina 25 miles out because the receiving towers are up high.
I haven't been paying much attention to the missing boat case. Just looked for an update and it said the boat was 65 miles off the coast. That's quite a ways for a non powered boat. I've never seen a sailboat even 10 miles out. It would take quite some time just to get that far out. It's even farther then where we go tuna fishing around the sea-mounts about 50/55 miles off the coast. Not even any info where the boat came from.
Yep! My first thought was a HOAX!
Yep! My first thought was a HOAX!
This is still the time of year with predominantly winter conditions exist which makes for uncomfortable sailing. Not too often you get dead calm out there any time of the year. I doubt any sane person would even attempt to go out in the conditions reported.
As for the 65 miles off shore, how was the position obtained.
As for the 65 miles off shore, how was the position obtained.
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From what I've read on the internet, there was only one line of bearing - so I suspect it was 'up to 65 miles' and somewhere along the line that fact got morphed into '65 miles'.