Television guidance (TGM) is a type of missile guidance system using a television camera in the missile or glide bomb that sends its signal back to the launch platform. There, a weapons officer or bomb aimer watches the image on a television screen and sends corrections to the missile, typically over a radio control link. Television guidance is not a seeker because it is not automated, although semi-automated systems with autopilots to smooth out the motion are known. They should not be confused with contrast seekers, which also use a television camera but are true automated seeker systems.
The concept was first explored by the Germans during World War II as an anti-shipping weapon that would keep the launch aircraft safely out of range of the target's anti-aircraft guns. The best-developed example was the Henschel Hs 293, but the TV-guided versions of this weapon did not see operational use. The US also experimented with similar weapons during the war, notably the GB-4 and Interstate TDR. Only small numbers were used experimentally, with reasonable results.
Several systems were used operationally after the war. The British Blue Boar was cancelled after extensive testing. A separate line of development led to TV-guided versions of the Martel missile to fill the anti-shipping role. The US AGM-62 Walleye is a similar system attached to an unpowered bomb, the Soviet Kh-29 is similar.
Television guidance was never widely used, as the introduction of laser guided bombs and GPS weapons have generally replaced them. However, they remain useful when certain approaches or additional accuracy are needed. One famous use was the attack on the Sea Island oil platform during the Gulf War, which required pinpoint accuracy and was attacked by Walleye bombs.