I have seen an ex-military comment on the recent pics of the Moskva and it somewhat corroborates the hypothesis that the ship didn't engage the defenses.
The person said that the AA radar was in the inactive position and the AA launchers were down in the wells. Obviously it is possible that they were retracted after the attack so it's not a hundred percent proof.
> AA radar was in the inactive position and the AA launchers were down in the wells
That is confusingly incompetent for a vessel at war, off the enemy’s coast, an enemy which manufactures anti-ship missiles and has been potting your side’s planes for weeks. I’m more liable to believe the radars were broken. It fits the pattern of logistical and maintenance issues across the Russian military.
Maybe they were. Anyway this starts to look like the Ukrainians did not overwhelm or disable the AA defenses. The more realistic explanation is that they had good intelligence and just knew the missiles have a good chance of landing (either due to incompetence or poor maintenance of the AA systems).
Maybe Ukraine felt like "trying to get lucky" and... lo and behold, they got lucky?
Not everything is necessarily down to intelligence. If Ukraine saw a chance to fire upon the ship, maybe they were like "Lets test out their missile-defense systems and see if they're as good as they claim..."
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If you have an intelligence-advantage against the opponent, you can fish for lucky chances more often, knowing that the opponent doesn't really have a good counter-response.
I believe these missiles cost a crapload of money, are slow to make and Ukraine has a small number of these. It would be irrational for them to use not one but at least two of them (some sources say there even were 3 hits) without a decent chance of a hit.
1. UK promises to ship anti-ship Harpoon missiles to Ukraine.
2. Ukraine was holding these Neptune missiles as the "ace in the hole" if the Odessa amphibious landing was ever to occur. After all, destroying enemy ships would kill most amphibious landing plans.
3. Since "Harpoons" are promised, Ukraine was suddenly in a position where it could use some weapons "recklessly", fishing to get lucky. As long as the UK's Harpoons arrive in time to defend Odessa in time, then the use of the Neptune missiles would be worth the tradeoff (even if there was a high chance of failure).
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On the other hand, Ukraine built the Moskva (in the Mykolayiv Shipyard). The 1990s refit of the Moskva was also handed by the Mykoalyiv shipyard (IE: Ukrainians not only built the original ship, but also handled one of the upgrades). It is quite possible that Ukraine had deep knowledge about the capabilities of the Moskva, and this was "less luck" than any of us can see.
Us in the USA may have overestimated the capabilities of the Moskva, while the Ukrainians knew more details about how / when to attack it for maximum chance of effectiveness. What they needed was a plan to defend Odessa however once those missiles were used up. UK providing a "backfill" of Harpoon missiles was therefore all Ukraine needed to go with the "lets try to get lucky" plan.
Perhaps the Russians got convinced by the internal logic if their own propaganda where they are engaged in a "special operation". By that logic it is ok to be relaxed about readines as well as have conscripts on board.
The person said that the AA radar was in the inactive position and the AA launchers were down in the wells. Obviously it is possible that they were retracted after the attack so it's not a hundred percent proof.