At the end of 2014 the world’s air forces possessed nearly 52,000 aircraft (fixed wing and helicopters). That’s down (because of accidents or retirement) about .8 percent from 2013. About 38 percent of those losses are from one country; Ukraine. In late 2014 Ukraine had about 400 military aircraft but 44 percent were lost to battle damage, capture or accidents in 2014 during the ongoing combat with Russian backed rebels and Russian troops.
Some Ukrainian aircraft were found to be unfit for service after having been neglected for too many years. Thus Ukraine lost about half its military aircraft in one year. Surface- to-air missiles took down 21 Ukrainian aircraft and one was shot down by an air-to-air missile fired by a Russian jet that was still in Russian air space. Other Ukrainian aircraft (helicopters) were lost to heavy machine-gun fire. At the moment the Ukrainian Air Force only has about 60 combat jets available and about as many helicopters. Russia has bullied Western nations into not providing weapons for Ukraine and thus is able to grind down the Ukrainians eventually.