US Military drones will be telling the world where they are going until at least 2014, according to an Air Force report. Earlier this week it was revealed that the US military's Predator and Reaper drones were broadcasting flight information to anyone who owned a cheap bit of software.

Initially the Pentagon denied the claims saying this was an old problem that had been addressed. However it later admitted that its command and control systems of the drones where using unencrypted signals which could be picked up by anyone.

But the air force has acknowledged the concern. Work on encryption began this year on the fleet, but it says it will not be finished until 2014. A former air force secretary, Michael Wynne, said if the enemy is able to collect and archive enough feeds, ''it could be useful in understanding our concepts of operation and many times how our tactics are used against them''. The enemy, he said, ''could essentially go to school on archived footage.''

The air force has known about the flaw for more than a decade, but they considered the threat minimal compared with the advantage the drones provide to commanders and troops in the field.