Destructors (DST) were standard streamlined bombs converted into shallow-water mines during the Vietnam War. Mks 36, 40, and 41 were, respectively, conversions of bombs Mks 82, 83, and 84. The Destructor's firing mechanism was developed very rapidly, and at the end of the war it was stockpiled. However, these mechanisms cannot have met the usual standards for re-liability or shelf life; hence the development of the Quickstrike Mines (Mks 62-65, see below). It is not clear how many, if any, Destructor mechanisms remain in U.S. war stocks.
Different Mods indicate different firing mechanisms: Mod 3 is magnetic,- Mod 4 is magnetic/seismic; and Mods 5, 6, and 7 are magnetic/seismic with K Tab Capability. As disclosed to the North Vietnamese in 1973 (as part of Operation End Sweep), the DST magnetic sensor is a thin-field magnetometer with selectable sensitivity. The seismic sensor is described officially as a detection battery. Presumably, it activates the magnetic sensor, so the mine cannot be exploded by a pure magnetic field.
Destructor Mk 36 was developed beginning in August 1966, and the first deployment was in June 1967. Mods 0 and 1 require retarded delivery; Mods 2 and 3 can be delivered unretarded against land targets. Mod 0 has fixed arming delay and fixed self-destruct. Mod 1 has selectable arming delay and introduces a probability actuator. Mod 2 has selectable self-destruct as well as selectable arming delay and probability actuator, and it is suited to unretarded delivery. Mod 3 adds a sensitivity option for increased countermeasures resistance. The arming delay al-lows the weapon to become physically stable in the presence of water currents and wave action and hence allows its firing mechanism to become magnetically stable.
Destructor Mk 40 was developed in 1968 for greater damage effectiveness against land targets. Mods 2 and 3 may be dropped unretarded against land targets using conical fins like those of Mk 36 Mods 2 and 3.
The bomb modification kit is Destructor Modification Kit Mk 75. The original program called for 22,125 kits in FY67 and 20,250 for FY68, but in July 1967 the program was increased to 111,865 kits and in November 1967 to 148,998; by 1970, over 300,000 had been made.
Destructors Mks 36 and 40 development ended in FY70, effort switching to Mks 41 and 42 (Quickstrike) following recommendations of the NOL Minetech study, Mine Advisory Committee Nimrod study, and an Op-95 ASW R&D assessment.
There is also a Destructor M117D Mk 59-0 (1985), which uses the standard air force 750-lb bomb, with Arming Device Mk 32-1, battery, and firing mechanism Mk 42-4; the total weight is 857 lb. It is intended for minelaying by B-52s.
MINE INDEX PAGE
Derick S. Hartshorn -