A cool device is an outer USB box for a full-size SATA storage with a proud inscription on the butt-end "Design by F. A. Porsche". The problem consists of non-definition in the system.
There is a rather rare storage inside the case, Hitachi SATA VLAT 7250VLA vol. 500 GB. The failure is also rather interesting: the disc is accelerated, and then it unparks heads and displays the state of readiness in the ATA terminal. At the attempt to refer to logicality or just read a descriptor it refuses to communicate over the interface and, according to registers, "loses its will for life".
The client ordered to recover data and a disc repair. Access to LBA is not a problem, especially if you know some design features of new Hitachi SATA discs. Repair is more difficult, the reason of such a strange behaviour can be cleared out only after repair.