Bhutan does not have an air force, nor (being a landlocked country) a navy.
India is responsible for military training, arms supplies and the air defense of Bhutan.
Bhutan's army is trained by the Indian Armed Forces.
[1] Historically, on 1 of January 1971 the Government of Bhutan decided to increase military personnel to 4,850 by recruiting additional 600-700 recruits and stricter regulations on liberation from service.
[2] Indian Air Force helicopters evacuated RBA casualties to India for treatment during Operation All Clear in 2003.