1: United States
Air Force department of United States of America is Aerial warfare branch of special armed force of the country, on the day of its formation it was considered as the part of the United States Army but in 1947 it was made separate department but now considered as one of the best air forces in the world. As about the size of this force then it is largest according to size and technology of this force, there are about 51 hundred crafts of this country with best radar system including 63 satellites, so this is also known as most strategic force of the Universe and according to reports this force is remained busy almost 12 months of year in any of the operation.
Russian Air Force is Known as Soviet Air Force which is new formed force that was came into being in 1992 but despite of recent formation this force is so far called as best in the whole world, with respect to size this is also one of the biggest because about 148000 people are there to perform their duties. This force has about 3125 crafts because this country is able to made their own aircrafts by their air force department, instead of this the also export crafts to some other countries like that of their weapons therefore this force is as much able to deal with any emergency in any country of the world because it has much resources and technology to deal.
People Liberation air force of China is also one of the best air forces in the world so their main purpose is to defend air space over their country and also around Taiwan, it was formed in 192o but made as best of the country in 1949 after independence of the country, this force is full of nest generation technology, combat crafts which is able to attack any place without any hesitation. As talk about the crafts in this force which are about 2500 in which over 1500 are combat therefore there is no doubt of calling this force the most competent air defense and they are increasing their technology in this department by using best radar system in crafts.