The War Zone reports what may be a first, an Uncrewed Surface Vessel apparently engaged an armed helicopter that was attempting to destroy it.
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This may have some relevance for the Coast Guard in that at some point a Coast Guard helicopter might be called upon to destroy a USV being used in a terrorist attack.
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It appears in this one-on-one engagement the helicopter had the advantage, being able to remain behind the USV out of the missiles field of view.
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The USV had two launch rails, but both were pointed forward. Had one been pointed forward and the other aft, the helicopter would have had a much harder time staying out of the missile field of view.
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Had it been two USVs vs a single helicopter, while the helicopter chased one USV it could be targeted by the other. The USV might employ something like the “Thatch Weave” that US Navy pilots employed against the more maneuverable Japanese Zero.
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It is possible the missiles on USVs were never intended to be used against aircraft. The intention might have been to employ them against a surface target as a way to reduce the effectiveness of the defense, as the USV approached the target.
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The article suggests that because the engagement occurred during the day, that the USV was attempting to bait the helicopter, but it might be that a long transit required some daytime transit to reach a distant port before sunrise.
Chuck Hill's CG Blog 
This is a 1st generation encounter. As you mentioned, what happens when one missile is pointed forward and one aft? When does the helicopter visually ‘see’ that – before or after the missile is launched. Also, what happens when the missiles are VL MANPADS and the helicopter doesn’t ‘see’ a launcher? Or if the drone launches a loitering munition that can be controlled to intercept the helicopter? Certainly, that’s coming.
The point here is that the helicopter will eventually be at a disadvantage, just as they are if they are approaching a surface warship. This was just a trial, but the enhancements and developments are bound to happen. And our future medium and large USVs better be similarly equipped with anti-air weaponry.
We are still in the early days USVs, UAVs, …
They will only get smarter and more capable.
The war in Ukraine is providing the motivation and real world experience to rapidly progress what these craft are capable of.
This pretty typical of the spiral weapons development gets into, measure, countermeasure, counter-countermeasure, etc, etc, etc. Pretty soon that cheap, simple, attritable weapon is no longer ship, simple, or attritable.
Some additional information and thoughts on how the missile armed USVs might be used.
Ukraine Has World’s First Navy Drone Armed With Anti-Aircraft Missiles – Naval News
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