Question for divers

[Ballsnall]

Originally Posted by fstbttms

You didn’t read far enough:

“Some experts say up to 2,000kg would have been needed.”

4 pipelines = ½ ton per charge. Semtex would weigh considerably less underwater with most of the weight due to the package used to shape the charge. You need a shaped charge to puncture the pipe otherwise you are just making a lot of noise.

80m dives aren't difficult or very technical and as has been discussed was probably just done on rebreathers to avoid the surface support needed. Shi#, I've done repetitive deco dives to 80m on scuba so this would be a walk in the park for a military diver.

The charges were most likely delivered prior to the diving operations, with the divers just placing the charges and arming them from the recreational vessel. The challenge here would have been to reduce the time on station so as not to arouse suspicion as I understand it there is a lot of surveillance on the pipelines.

A well trained crew could have pulled it off in an afternoon would be my guess.

[LakeSuperior]

Originally Posted by fstbttms

Clearly. But apparently we have a whole lot of underwater demolition experts here

I guess I don't see what point you are trying to make? Do you have UW demolition expertise derived from scrubbing boat hulls

[fstbttms]

Originally Posted by LakeSuperior

I guess I don't see what point you are trying to make? Do you have UW demolition expertise derived from scrubbing boat hulls

The point is that there are a lot of laymen in here making claims about how easy it would be to pull this off, what equipment would be needed, how long (or little) time it would take etc., etc.

When a Navy SEAL chimes in, then I'll believe that somebody here has a clue about this.

[LakeSuperior]

Originally Posted by fstbttms

The point is that there are a lot of laymen in here making claims about how easy it would be to pull this off, what equipment would be needed, how long (or little) time it would take etc., etc.

When a Navy SEAL chimes in, then I'll believe that somebody here has a clue about this.

Clearly you missed my point completely!

[AKA-None]

Originally Posted by fstbttms

The point is that there are a lot of laymen in here making claims about how easy it would be to pull this off, what equipment would be needed, how long (or little) time it would take etc., etc.



When a Navy SEAL chimes in, then I'll believe that somebody here has a clue about this.

Having partied with some I doubt any would chime in unless they are more talkative than in the past
Even liquored up they tended to be vague about details

[fstbttms]

Originally Posted by LakeSuperior

Clearly you missed my point completely!

Please enlighten me

[AKA-None]

May I point out we know little about what many members have experience with in past life

[boatman61]

Shaped thermal charges could be smaller and placed stratigically could do the trick.

[Scubaseas]

Originally Posted by fstbttms

The article indicates that the Bavaria 50 was not a suitable boat- these dives required a bell and and that boat could not have carried one. If indeed the Bavaria 50 was involved at all, a second vessel would likely have been needed, as the article states.

Have you done any technical diving?

80 m simply is not that deep. I've done lots of dives on Navy tables to 68m to 73m on air albeit the bottom time is like 4 to 6 minutes. it can be much longer if using Trimix/Stargon. 80m on SCUBA is not hard to do. You don't need a diving bell to get to and from 80m. And yes I am a professional diver the last 28 years.

So that part of the article seems to be wrong or at least not quite right. I see videos of T72s and T80 tanks being blown up with RPGs and shaped charges which I'm pretty sure do not weigh in at 2000kg. I have no idea what you need to blow a hole in the Nordstream pipeline. I suspect that the person that wrote the article doesn't know either. Perhaps you have enough knowledge to determine what is and what isn't doable? If it's encased on concrete a hydraulic drill works just fine at 80m. The pump and motor are about the same size as a genset.

[fstbttms]

Originally Posted by Scubaseas

So that part of the article seems to be wrong or at least not quite right. Perhaps you have enough knowledge to determine what is and what isn't doable?

I made no claims or statements about how any of this could be accomplished. I simply pointed out what was said in the article. If you have an issue with that, take it up with the author, not me.

[Scubaseas]

Originally Posted by fstbttms

I made no claims or statements about how any of this could be accomplished. I simply pointed out what was said in the article. If you have an issue with that, take it up with the author, not me.

"The point is that there are a lot of laymen in here making claims about how easy it would be to pull this off, what equipment would be needed, how long (or little) time it would take etc., etc...."

So you have the knowledge to determine who is right and who is wrong? The SEALS I know don't do math that well. I'm not sure a SEAL would be the ultimate determinator of what would and would not work. I have no idea. I don't do destructive engineering. I'm sure any SEAL could look up the dive profile. The explosive part maybe not so much.

I do know a lot about technical diving i.e. decompression diving though and can make a claim about how hard it would be to access the pipeline if it's in 80m of salt water.

Dude, it's a friggin Internet forum. Lots of idle speculation here and apparently the only person upset seems to be...you?

[LakeSuperior]

Originally Posted by fstbttms

Please enlighten me

I think my point was illustrated better than I in subsequent posts.

[hpeer]

I also have interest in this question and appreciate the answers, However there are some mistaken assumptions going on.

Regarding the amount of explosive, the question really is about 2 sites, not 4 as 2 were together and a 3rd separate.

Of the 2 explosions they registered 2.4 and 2.6 on the Richter scale.

These were not "shaped" charges to punch a hole. One blast took out 50 METERS of pipe, the other took out 150 METERS of pipe.

The pipe is roughly 1 meter in diameter, the wall is about an inch thick, a bit more IIRC, covered with a few inche's of concrete.

So that is why the volume of explosive is estimated as being so high, large.

This quantity of explosive needs to be delivered to 2 different pipes, in the open ocean. Assuming 2 divers per dive. A total crew of 6 onboard. No other support vessles or shoreside assistance. One voyage, up to 2 weeks.

These are the parameters around the incident already known from the investigating governmemts.

How many dives needed?
Do you need to establish a down line to the bottom or can you just jump in and swim?
How do you guide the explosives to the pipe once on the bottom?
How do you assure the sailboat makgovernments. pick up?
How long does this entire operation take?I
This was a charter boat, the charter company complained the boat was returned dirty. What are the chances this operation could be completed without leaving some noticeable damage, scratches, abrasions, whatever, that the charter company would notice?


Thanks

[Chris31415]

James Bond would have used an Oyster.

[Jammer]

Originally Posted by hpeer

How many dives needed?

One. You need a rebreather and trimix. Deco time will be considerable.

Do you need to establish a down line to the bottom or can you just jump in and swim?

Depends on the current. There are people who will do a hypoxic hot drop in current but you have to be good, bold, and lucky to land where you want. (Depths below 60m require breathing gas that does not have sufficient oxygen to be breathable at the surface; these are referred to as hypoxic dives.)

How do you guide the explosives to the pipe once on the bottom?

I don't know anything about explosives, but I know that while moving things around underwater you use lift bags to balance them so that they are neutrally buoyant and then maneuver them into position. Current is your enemy in proportion to the size of the item. Weight doesn't matter much. Cars are heavy and so are boats; people guide them around underwater with ropes and lift bags.

How do you assure the sailboat makes the pick up?

The preferred solution is to have an anchor line or a shot line (a line that is held to the bottom by a bag of lead shot with a buoy at the surface) to control the ascent and serve as a reference. Absent that, the divers shoot an inflatable SMB (surface marker buoy) while adrift decompressing, and the boat looks for it. Finding divers that want to be found is not ordinarily difficult if the sea state is reasonable, unless there is a ripping current.

How long does this entire operation take?

Think in terms of a few hours overall to get a reasonable amount of bottom time.