June 13th 1944 marked the first use in combat of an unmanned powered flight weapon, the V1 flying bomb.

A fall back project in case the V2 proved impossible to develop, the much simpler 400 m.p.h. flying bomb was to become a familiar sight and sound in Belgium and South East England.
Hitler had, since defeats started building up 2 years previously, staked much hope on these weapons turning the tide in his favour, an impossible task probably, though Eisenhower would later reflect that had the V1 been en-masse at the Channel ports in England before D-Day, they could have caused serious problems.

Soon civilians would hear the pulse jet sound, sometimes see this odd looking object, the time to worry was when the engine cut out, seconds later a ton of explosive would hit the ground.

Though she was a young girl at the time, my Mother clearly remembers seeing and hearing these strange little craft, the forerunner of todays cruise missiles, three months later, worse was to come, the A4 (V2) ballistic missile, for which there was no warning and no countermeasures once launched.

An overview of the V1 'war';
http://www.geocities.com/Yosemite/Cabin/7226/V-Weapon.html

http://www.fact-index.com/v/v1/v1_flying_bomb.html

Concentrating on the those on the receiving end, with much more besides, with on this site, a South London bias:
http://www.flyingbombsandrockets.com/

Some pictures;
http://www.btinternet.com/~paul.steele/V1_SCHEMATIC.jpg

http://www.btinternet.com/~paul.steele/v1ramp.jpg

http://www.btinternet.com/~paul.steele/V1_1.jpg

http://www.btinternet.com/~paul.steele/v1fall.jpg