The Grillo class: a tracked torpedo-boat experiment

The class was intended for stealthy torpedo attacks, but its low speed and unusual tracked arrangement made that employment deeply problematic. Only four were built, while aircraft-delivered torpedoes such as those carried by the Royal Navy's Cuckoo offered a more practical way to cross defended waters. The same tracked hull might have been more useful as a landing craft if produced in numbers and supported by heavy covering fire. That alternative would still have demanded dangerous close support from the battle line. The four boats show an inventive answer to Adriatic obstacles whose assigned torpedo mission exposed their crews to a poorly matched design.