User:Bullzeye/SM-70

The SM-70 (Splittermine Modell 1970) was an East German directional antipersonnel mine developed specifically for use in preventing defection across the Inner German Border (Grenze) into West Germany.

Design
First fielded in 1970, the mines were cone-shaped, trip wire activated, and mounted to concrete posts along the line of climb-resistant prefabricated steel mesh fence. In some cases, they were mounted directly to the fence itself. They were aimed parallel with the fence line, and intended to kill or incapacitate anyone attempting to climb or cut through the fence.

Service
Beginning in late 1970, approximately 60,000 SM-70s were installed along with additional strips of buried PMN anti-personnel mines on 440km of particularly escape-prone rural sections of the East German border. Installation of the mines cost 100,000 Ostmarks per kilometer, for an total cost of over 44 million marks. The mines were not used on the Berlin Wall.

Although referred to within the Border Guards by the National People's Army designation G-501, for propaganda purposes the mines were referred to as "Automatic Firing Devices" (German: "Selbstschußapparat") in public documents. The cryptic description led to the public perception that the mines were technologically-advanced automated sentry guns rather than simple static trip-mines, a misconception held even by Western intelligence agencies. In fact, no such technology existed during the lifespan of East Germany, and the mine was actually more similar in capability to an oversized spring gun, but the rumors provided an additional psychological deterrent to would-be refugees.

In a prominent design flaw, the trip wires proved sensitive enough to trigger the mines if a bird rested on the wire, resulting in a large number of accidental detonations in early deployment; this led to an inert "bird wire" being strung slightly above the first actual trip wire to give the birds something to rest on without risking a discharge. This proved only somewhat effective, as the mines still regularly suffered unintentional detonations due to heavy winds, snow and ice accumulation, falling tree branches, bramble overgrowth, and rock-throwing West Germans.

Michael Gartenschläger
The true nature and purpose of the SM-70 was eventually determined after Hamburg resident and former East German political prisoner Michael Gartenschläger—who had led a party of six defectors in a successful escape across the border in 1971—successfully infiltrated the border defenses on 30 March 1976, dismantled a live SM-70 from its mount, and returned safely to present the mine to West German authorities for inspection. Against official advice, Gartenschläger made a second successful trip to the same section of fence on 23 April and retrieved another live SM-70. The event made West German newspapers, and tipped off the Border Guards that the sector was being targeted for sabotage. A special 29-member task force was assembled to prepare concealed firing positions in the area and set up an ambush for the culprit. On 1 May 1976, as Gartenschläger was climbing over the East German fence for his third attempt, he was captured in the beam of a searchlight and blown off his ladder with a burst of automatic gunfire. There was no request for surrender.

Following the recovery and analysis of the intact SM-70 in 1976, international diplomatic protests over the mine's disproportionate lethality led to East Germany slowly phasing the mine out of service, with the last being removed 30 November 1984. The buried PMN mines, however, remained in place until the fall of East Germany in 1989.