Patent ID: 6889624

Claim:
In combination with a towing line extended from a retrieval ship, a grapple anchor device hooked to the towing line for underwater towing of an unmanned vehicle toward the retrieval ship, comprising: an elongated housing; prong means pivotally connected to the housing for engagement by the tow line under a towing tension during said towing of the unmanned vehicle; rod means coupled to the unmanned vehicle by an anchor line and extending into the housing for displacement therein in response to said towing tension exerted by the tow line; lock means mounted on the housing for holding the prong means in a towing position on the housing hooked to the tow line during said towing of the unmanned vehicle; and actuating means operatively connected to the lock means within the housing for release of the prong means from the tow line in response to a reduction in said towing tension in the tow line upon termination of said towing of the unmanned vehicle.