Drones fired more weapons than conventional warplanes for the first time in Afghanistan last year and the ratio is rising, previously unreported U.S. Air Force data show, underlining how reliant the military has become on unmanned aircraft.
The trend may give clues to the U.S. military's strategy as it considers withdrawing more troops from the country, while at the same time shoring up local forces who have struggled to stem a worsening Taliban insurgency.
U.S. President Barack Obama said in 2013 that the Afghan drawdown after 2014 and progress against al-Qaida would "reduce the need for unmanned strikes," amid concerns from human rights groups and some foreign governments over civilian casualties.