Search and Rescue - Lasers and Signaling Devices

[Dan]

If we are going to go down the road of developing underwater communication devices for SOS, wouldn't it be first prudent to simply have a buddy?

Yes. I dive with buddy. I’m just trying to answer @Manjula Ellepola question, below

Everybody is talking about lights, what about acoustics? For PLBs/lights the diver needs to have surfaced. What if the diver is underwater? If there was a device that can communicate underwater then the diver could send out an SOS as well as the device could act as a beacon so search divers can home in on the distressed diver.
This was something I discussed with Cameron and he was very interested in this idea and offered to test the prototypes. For example if both Cameron and his mum had such devices the outcome could have been a whole lot different. However a lot of SB members thought such a device is a crutch and in fact would be detrimental as divers would get complacent. Quite a few said that a device like this is not needed at all
Given the tragedy that just unfolded I would like to hear your comments on such a device which can change the future of diving in a positive way.

 

[Dan]

I think that unit works to 1km or more..not sure of price but I think it is around the same as an upper end dive computer.
Most of the devices mentioned here are useful at the surface, but what about if you cannot get out of your entanglement DanT? If for example Cameron could have sent a message to his mum she would have been in a much better position to help him rather than not knowing anything of what transpired.

Then I drown.

 

[ggunn]

Everybody is talking about lights, what about acoustics? For PLBs/lights the diver needs to have surfaced. What if the diver is underwater? If there was a device that can communicate underwater then the diver could send out an SOS as well as the device could act as a beacon so search divers can home in on the distressed diver.

It seems to me that any distress a diver could get into underwater would already be over, one way or another, by the time anyone but another diver who happened to be really close by could get to him. Another thing, the way our ears detect directionality of sound is by small phase differentials between what we hear in one ear from the other, but sound travels so much faster in water than in air that the phase differences are a lot smaller, so we can't usually tell what direction a sound is coming from when we are submerged.

 

[BRT]

It seems to me that any distress a diver could get into underwater would already be over, one way or another, by the time anyone but another diver who happened to be really close by could get to him. Another thing, the way our ears detect directionality of sound is by small phase differentials between what we hear in one ear from the other, but sound travels so much faster in water than in air that the phase differences are a lot smaller, so we can't usually tell what direction a sound is coming from when we are submerged.

I've been separated from my wife and another buddy in cold green water and could hear my wife clanking her tank as though she were next to me but I couldn't find her. No clue as to direction.

 

[ggunn]

It is illegal to point a laser toward an aircraft ... in many places

Come arrest me - please!

 

[Manjula Ellepola]

Then I drown.

Why so fatalistic DanT? You are well known on SB for promoting safety devices. If you have enough air then you have a chance for someone to rescue you if you were able to get a message out and they can find you. These days people don't go to the convenience store without their smart phones. Is it so hard to stretch you imagination that a communication and navigation tool would be very useful in a hostile environment?

I've been separated from my wife and another buddy in cold green water and could hear my wife clanking her tank as though she were next to me but I couldn't find her. No clue as to direction.

There you go! Buddy separation happens more than people like to admit. The only option is to surface and hope the buddy surfaces as well. If you had a device that enabled you to reunite with your buddy in a few minutes you continue the dive with much less stress

 

[Johnoly]

@fsardone you did a really nice job of covering why lasers aren't the best choice, but please stop with the "OMGLASERSWILLBURNTHEPILOTSEYEBALLSOUTANDALLTHEPLANESWILLCRASH" hyperbole. ...
........A bunch of us lost a friend, and if he had any one of several signaling devices, he might have been found, waterlogged and dehydrated, but alive. We owe it to him to be honest and realistic.

Late reply, went Jupiter diving today - it's the end of lobster season here.
@fsardone and @Hoag have both educated us "Don't shine the laser at aircraft". So I'll shine the green laser straight up in air in a circular motion which from far away to an aircraft pilot will look like a GIANT CONE pointing directly down to my location and head.

But it's just 1 or 2 aircraft. I'm much more likely to see 10, 20, or 30 cargo & cruise ships passing by who are NOT WEARING night goggles and will see the green laser to investigate or atleast report a green flash to SAR.

In addition, the place where the beach diving occurred is LOADED with condo's. A green laser shined inside of the condo to a cranky old retired person is sure to get them angry enough to report it. (that is my exact type of Jupiter diving condo area also).

So if an aircraft >> it gets pointed straight up to form an " I'M HERE LOCATION CONE ",,,,,,If it's a ship/condo, I flash them repeatedly till I see them turn that massive ship towards me or slow/stop and launch a rescue boat.

But a green laser is no doubt going to get a rescue if seen, pointed straight up for aircraft or at a ship/condo.
Green laser beats an IR beacon to the 30 passing ships and hundreds of condo windows.

 

[Dan]

Why so fatalistic DanT? You are well known on SB for promoting safety devices. If you have enough air then you have a chance for someone to rescue you if you were able to get a message out and they can find you. These days people don't go to the convenience store without their smart phones. Is it so hard to stretch you imagination that a communication and navigation tool would be very useful in a hostile environment?...

Of course I'd try all option to remove myself from entanglement while there is some air left in the tank. I carry a knife. I have DiveAlert to blow SOS sound. However, my buddy and I agree on the case of separation underwater, we would search for each other for a minute and surface. So, he'll be on the surface waiting & searching for me, while I'm stuck underwater alone trying to free myself, making quacking sound with my DiveAlert, until I run out of air.

May be about time he & I talk about that sonic device that you mention earlier, UDI-28 Wrist Unit - UTC

Thanks
Dan

 

[BRT]

Why so fatalistic DanT? You are well known on SB for promoting safety devices. If you have enough air then you have a chance for someone to rescue you if you were able to get a message out and they can find you. These days people don't go to the convenience store without their smart phones. Is it so hard to stretch you imagination that a communication and navigation tool would be very useful in a hostile environment?

There you go! Buddy separation happens more than people like to admit. The only option is to surface and hope the buddy surfaces as well. If you had a device that enabled you to reunite with your buddy in a few minutes you continue the dive with much less stress

True about the device, but noisemakers don't help and it is not worth it to me to carry one of the directional buddy finders.

 

[IncreaseMyT]

So sounds like consensus is an IR beacon and the Nautilus? As a pair.