The M50 Ontos and M56 Scorpion were two very light tank destroyers, largely developed as a result of the shock to US army doctrine caused by the Korean War. The army was forced to look at its plans for dealing with the huge number of Red Army tanks, and came up with a system that involved the use of massive minefields, supported by large numbers of ‘expendable’ tank destroyers - light, fast heavily armed vehicles that could deal with the oncoming Red hordes. (quite what the crews of these vehicles would have made of that role was apparently never considered).
The resulting vehicles were rather different in style. The M56 Scorpion, the less successful of the two, was a light vehicle carrying a 90mm gun. It’s combat record was very limited, and involved a single platoon of one company that served in Vietnam in 1965-66, where it was used for direct fire support of the infantry.
The second, the M50 Ontos, was a rather odd design. It carried six recoilless rifles mounted on the sides of the superstructure of a rather vulnerable vehicle. Rather oddly there was no way to reload the guns from within the vehicle, or while moving. In addition the recoilless rifles gave away their positions rather dramatically when fired, so the plan was for the vehicle to fire one salvo and then quickly move to a new position, where the crew would then have to bail out of the vehicle to reload their guns, while hoping that their movement hadn’t been spotted! As with the M56, this also didn’t see any use as an anti-tank weapon, but it did see more lengthy combat in Vietnam, where the powerful rifles proved to be very effective anti-building weapons, playing a significant role at the battle of Hue, and a lesser one at Khe Shan. It was helped by the development of an anti-personnel shell for the rifles. Ultimately neither of these two was a success - they were too vulnerable, were never produced in the vast numbers that had been planned, and were made obsolete by effective anti-tank missiles.
It was a good choice to cover both of these vehicles in a single book - neither of then would really fill a book of its own, but they combine nicely. The book is well illustrated, although most pictures are of the more striking looking Ontos, which also had a longer service record.
Design and Development
Foreign Service and Variants
Author: Kenneth W. Estes