(Reuters) - China's air force celebrates the 60th anniversary of its founding with aerial displays and parachutists dressed like fairies from a Chinese folk tale, but its ambitions in space worry analysts in Washington.

Following is a brief overview of China's defense forces:

WORLD'S BIGGEST ARMY:

- The People's Liberation Army (PLA) was born out of the Red Army, a 5 million-strong peasant army that swept Communist leader Mao Zedong to power in 1949. Soviet expertise helped organize it into the more cohesive force that fought in the 1950-1953 Korean War alongside North Korea.

- China's official military budget will grow to 480.7 billion yuan ($70.41 billion) in 2009, up 14.9 percent on year, in line with nearly two decades of double-digit budget rises. Many analysts believe real military spending is significantly higher.

- By comparison, President Barack Obama has sought roughly $534 billion for the Pentagon's core budget in fiscal year 2010, not including war funding, a 4 percent rise from 2009.

- China has never renounced the use of force to bring self-ruled and democratic Taiwan, which it considers its sovereign territory, under Beijing's rule.

- China's 2.3 million-strong armed forces are far bigger than the world's second-largest military, that of the United States, whose forces number around 1.5 million.

- China is trying to transform the PLA into a smaller, sleeker modern force capable of short, high-intensity conflicts against high-tech adversaries.

PLA NAVY:

- The PLA Navy has about 290,000 personnel, many on aged vessels. President Hu Jintao has made the navy's modernization his personal project.

- The navy has about 72 combat ships. It is upgrading destroyers and frigates to range further and strike harder.

- The navy's mandate includes protecting oil supply lanes to the Middle East. Chinese warships also assist in anti-piracy patrols in waters off Somalia.

- China bought the Varyag, a semi-finished Russian aircraft carrier, a few years ago, but it is unclear whether the Varyag will be put into service or used as a training deck and template for a Chinese-made carrier.

- China in recent years has bought eight Russian-made non-nuclear submarines, adding to four bought in the 1990s. It has also built or is planning its own new submarines, including nuclear-powered subs, to replenish its aged fleet of nearly 60.

PLA AIR FORCE:

- China boasts the world's third-largest air force, with about 400,000 personnel and 2,000 combat aircraft.

- An October 1 parade marking the 60th anniversary of the People's Republic of China featured bombers, unmanned aircraft, reconnaissance and rescue helicopters. Pride of place went to the F-11, a fighter adapted by China from Russian models.

MISSILES, NUCLEAR WEAPONS:

- China's arsenal includes between 100 and 400 nuclear weapons, controlled by the Second Artillery Corps. China has pledged never to be the first to use nuclear weapons.

- Its deterrent force includes intercontinental ballistic missiles, and land- and submarine-based missiles

- U.S. strategists say China may develop anti-ship ballistic missile capability to deter aircraft carriers

- The successful missile "kill" of an old satellite in early 2007 represented a new level of ability for the Chinese military.

($1=6.827 Yuan)

Sources: Reuters, International Institute for Strategic Studies. http://www.globalsecurity.org/index.html; U.S. Department of Defense; Congressional Research Service; Federation of American Scientists)

(Writing by Ben Blanchard and Lucy Hornby; Editing by Alex Richardson)