Update: Since posting, the antenna has been identified as the SeaWatch system from Thayer Mahan.

Unidentified Wave Glider seen off U.S. Coast
Flag A photo has been shared on Instagram asking 'what is this?' And there is a great video on Facebook. Well, it is a version of the Wave Glider with a previously unseen aerial attached. The small uncrewed surface vessel (USV) was found by civilians off Key West. The owner of the USVe is unclear but given its location and the nature of the antenna it appears possible that it is U.S. Navy related.
Unidentified Wave-Glider off USA Coast - Covert Shores
Image credit: Lauren Taylor

The Wave Glider is built by Liquid Robotics operating out of Sunnyvale California and Hawaii. The company is now a subsidiary of Boeing.

Wave Gliders work by harnessing the oceans wave motion to generate enough power for mobility. Below the surface, attached to the 'surfboard' vessel by an 8 meter umbilical, is a submarine float with six sets of 'wings'. These are moved by the waves, generating power.
Unidentified Wave-Glider off USA Coast - Covert Shores
A file photo of the winged float beneath the Wave Glider. Photo: Liquid Robotics.

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They also have solar panels on the deck which provide additional propulsion power. This increases mobility and precision and helps to navigate challenging ocean conditions (doldrums, high currents, and hurricanes/cyclones). The solar system also recharges batteries that power sensors.

The Wave Glider has both civilian and naval applications so it is not easy to identify the owner of this particular example. Liquid Robotics advertises that they can be using in ASW, ASuW, ISR and as a Communications gateway.

Wave Glider Specifications
Water Speed: Typical 1.3kts
Endurance: Up to 1 year (varies based on operating conditions and location)
Operating Water Depth: > 15m
Station Keeping: 30m radius
Payload Capacity: 7 modular bays (93L)
Tow Capability: 500kg (drag dependent)
Average Continuous Power: 5W – 20W
Max Solar Collection: 192W (nominal)
Battery Capacity: 0.9kWh – 6.8kWh rechargeable
Communications: Satellite, Cell, Wi-Fi

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Since originally posting the antenna has been identified as the SeaWatch system from Thayer Mahan. The ID was made by Twitter user Johann_U96. SeaWatch is an autonomous electronic surveillance package mounted on a Wave Glider autonomous surface vessel. Its purpose is to provide a long endurance maritime capability that can detect electronic emissions related to illicit maritime activity. SeaWatch detects emissions that are too weak to be picked up by shore sites. It also assists in localizing emissions by providing additional bearings from a different aspect relative to the emitter.
See the Thayer Mahan website
SeaWatch Wave-Glider off USA Coast - Covert Shores

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