Flounder for Sevastopol
Air delivered JDAM gliding sea mines would enable Ukraine to severely crimp Russian naval ports where cruise missile launch platforms are based.
During the Vietnam War a multifaceted US air campaign against North Vietnam brought the communist North Vietnamese at the bargaining table in Paris to sign treaty largely agreeing to U.S. terms, with a major component of that campaign being dedicated air delivered sea mines deployed to close the approaches to Haiphong harbor, among others, beginning in May 1972 and continuing through the signing of the Paris Peace Accords in January 1973.
Since the 1970s the US Navy has moved away from dedicated sea mines to conversion kits for standard 500 lb mk82 and 2,000 lb mk84 bombs, substituting magnetic and acoustic fuses for the impact fuses appropriate for airdropped bombs. Some smart soul in the military procurement chain, perhaps channeling extensive Lego experience, realized that if one also bolted a JDAM precision guidance kit to the mk84 bomb body fitted with a sea mine detonator one would get a precision guided air dropped sea mine, and if one bolted both a JDAM kit and the fold-out ER wing kit to a sea-mine configured mk82 one would get an air dropped gliding sea mine which could glide 40 miles from the dropping aircraft, splash into the water at a precise location, and then wait for a ship to pass within range matching its target parameters before blowing up.
There are also a rocket-booster bolt-ons in the JDAM parts bin which open all sorts of possibilities for even more extended range air deployment, or even potential surface launch from sea or land, of these precision guided air delivered bomb conversion sea mines.
The US Navy has not yet bought that Lego set, so that’s a set of thoughts for another day.
Sailors nicknamed these air delivered mines after fish: They call the larger not-gliding mk84 JDAM sea mine the Skipjack, and the glide-wing-equipped mk82 JDAM-ER sea mine the Flounder.
Per open sources, as of March 2023 the US has provided mk82 JDAM-ER precision guided extended range glide bombs to Ukraine, and those are already in use.
To provide Ukraine an air launched extended range sea mine capability, the only additional bit from the JDAM Lego bin would be the sea mine detonators.
Here’s a map showing a 40 mile radius centered on the Sevastopol harbor mouth. This is the publicly acknowledged glide range of the Flounder airdropped from an aircraft at 30,000ft altitude.
This is pretty close given Russian long range SAM envelopes over Crimea, so any air dropped mining ops, even with the JDAM glide variant, would need a robust SEAD component.
But Ukraine has been pretty innovative, recently conducting attacks into Sevastopol harbor with multiple small naval ROVs.
If Ukraine fitted their seagoing ROV guidance system to a larger vehicle, perhaps operating partially submerged, and loaded it with a number of sea-mine configured mk82s or mk84s rigged to be dropped over the side once the vehicle reaches specific locations, they could make life very difficult for any harbor within the vehicle’s range.
This semiautonomous ROV minelayer could travel to a precise location, drop one mine, move to another and release another mine, and so on, returning to Ukrainian territory for more mines when empty. A tiny fleet of ten of these, assuming a completely arbitrary guesstimated loadout of four mines, could place 40 mines in a single night. And open source discussion of these mine fuses indicates they have very sophisticated capabilities, so something as simple as “wait N days before activating” would be trivial. Staggering activation of a week of covert mining could see a field of hundreds of mines in the Sevastopol harbor approaches activating simultaneously. With covert placement Ukraine could even issue the required notice to mariners announcing they are closing Sevastopol harbor before the scheduled activation without giving the Russians time to sweep the fields.
And not just Sevastopol - given enough range, other Russian Black Sea naval ports could also be held at risk, albeit with longer transit times.
And with sufficient range, after Ukraine’s immediate wartime needs are met, I imagine militaries which can get mk82/mk84 bomb bodies and sea mine fuses, or develop their own similar, would be very interested in buying a fair number of autonomous ROV minelayers.
I can just imagine the sleepless nights this capability would give PLAN invasion planners if Taiwan bought a few hundred autonomous minelayer ROVs.
And given nobody has a patent on clever, USN and our allies planners should be having a few sleepless nights of their own about this type of thing.