The SA-7 GRAIL or Strela-2 is a man-portable, shoulder-fired, low-altitude surface-to-air missile (SAM) system similar to the US ArmyREDEYE[?], with a high explosive warhead and passive infrared homing guidance. The SA-7 was the first generation of Soviet man portable SAMs, introduced in the 1960s. Although the SA-7 is limited in range, speed, and altitude, it forces enemy pilots to fly above minimum radar limitations which results in detection and vulnerability to air defence systems[?]. The SA-7 is a tail-chase missile system[?] and its effectiveness depends on its ability to lock onto the heat source of low-flying fixed and rotary-wing aircraft.
... chain produces a proton-motive force, pumping H+ ions across the membrane; this produces a concentration gradient which can be used to power ATP synthase. This pathway is ...