>But Mykhailo Podolyak, a top adviser to Ukrainian President Volodymyr Zelenskyy, says Ukrainian intelligence believes that Russian forces planned the attack as a pretense to escalate the war in Ukraine.
>"The Crimea bridge incident gives the Russian military a convenient alibi for all of its defeats in southern Ukraine," Podolyak told Ukraine's national broadcaster.
https://www.npr.org/2022/10/13/1128625322/crimea-bridge-atta...
These pipes lay at ~70 m depth so the drones can be wire-controlled. A small fishing vessel would be enough to deliver them.
That's not drag a hose behind a commercial drone. That's specialized equipment with trained operators. I just don't see Ukraine being able to pull that off.
...since an underwater explosion (particularly one underneath a hull) can produce greater damage than an above-surface one of the same explosive size. Initial damage to a target will be caused by the first shockwave; this damage will be amplified by the subsequent physical movement of water and by the repeated secondary shockwaves or bubble pulse. Additionally, charge detonation away from the target can result in damage over a larger hull area. [1]
The pipes have ...two layers; the inner pipe steel which is between 27-41mm thick with antifriction coating and a concrete steel outer coating between 60-110mm thick with corrosion protection... [2], far from the 'several inch thick pipes encased in a foot of concrete' you mention. They were also under high pressure, probably around 200 bar at point of attack [3]. Given that the pipes are at a depth of around 70 meters there this means they had an overpressure of around 193 bar so it would not have taken that much of a crack to cause them to rupture. Once ruptured the whiplashing effect - think what happens to a water hose when you turn open the tap but now with 193 bar of pressure behind it - would take care of the rest.
[1] https://wikiless.org/wiki/Underwater_explosion?lang=en
[2] https://www.newcivilengineer.com/latest/nord-stream-risk-of-...
The motivation should make sense, Russia makes sense, it was probably Russia.
And in regards to past Russian behavior even more realistic.
This is very wrong. My brother is a technical diver, and after the blast I had a long chat with him about what it would do to achieve this. After going over the location, the estimated amount of explosives needed to break the pipes, and the depth, he came to the conclusion that he could have done it with 2 friends and a budget of ~10k€.
This was before these new pictures that paint a picture of a more powerful blast than he assumed, but it is still well within the capability of a bunch of very determined activists. This absolutely didn't need to be a state actor.
I came out of the discussion with a newfound appreciation just how fragile a lot of our billion-euro infrastructure is, and how easy it would be to disrupt.