Buzzing like an oversized electric razor, hairdresser Wang Qiang's home-made airplane skids over grassland before soaring into a vast blue sky, in a rare flight allowed by Chinese authorities.

Wang spends his days trimming and shaping at a hair salon in eastern China's Zhejiang province, and his evenings working on the rickety one-seater craft.

He is one of a tiny -- estimates say their numbers stand at around 2,000 -- but growing number of Chinese private aircraft owners who are grouping together to challenge restrictions which ban them from almost all the country's airspace.

Wang's machine -- with a stainless steel frame, wheels from a motorised wheelchair, and a seat scavenged from a go-kart -- took eight months to build and cost 30,000 yuan ($5,000).

It can reach altitudes of 3,500 metres and speeds of 90 kilometres an hour (56 mph), he says.

"In the countryside people play mahjong after finishing work... but I like to fly," said Wang, 37, who grew up spreading manure and picking corn on a farm.

"We want the government... to give us more room to enjoy the skies, and enjoy flying," he said. "If ordinary people, even vegetable-cutting housewives can fly, that would be best."

Around 20 private planes, microlights and motorised paragliders took to the air in a valley in Hexigten Banner, in China's remote Inner Mongolia region at the weekend, in the country's first festival of its kind after organisers obtained special permission from the authorities.

The gathering was inspired by the "fly-ins" of the US, which can see thousands of aviators converge on a single location -- but the private flying restrictions meant enthusiasts had to reach the festival overland.

Plans for an earlier gathering in Beijing in 2011 were cancelled by officials citing safety concerns.

"We are very far behind the US," said organiser Zhang Feng, of China's Aircraft Owners and Pilots Association. "We want to use this event to promote the opening up of China's airspace."

Ding Lin, a retired Chinese air force pilot who owns a two-seater plane made in France, added: "We are trying to push towards freedom of flight.

"In 10 years you will come back and the whole sky will be full of planes," he said, before wiping down his plane's shining red propeller.

But such aspirations face formidable opposition. China's military controls nearly all of the country's airspace, and despite promises of reform has only opened a few areas to private flights. "You can barely fly anywhere... some people have travelled here because they don't have the opportunity to fly anywhere else," said Zhang.

In the shadow of green hillsides dotted with Mongolian yurts, the aviators lamented that flight is a symbol of liberty, but one only open to those well-connected enough to strike deals with local authorities, or wealthy enough to afford fines of up to 100,000 yuan for taking to the air illegally, a practice known as "black flying".

"Often there is no alternative to black flights," said Zhang, adding: "If you have to report flights in advance, you lose the sense of freedom."

Most private Chinese pilots are wealthy, given the costs of training and licences -- up to 200,000 yuan, visitors to the festival said -- but there are signs of an emerging interest in flight among China's army of backyard DIY inventors and tinkerers.

"Flying is a beautiful thing," said Shu Bin, a mechanic from Zhejiang who soars over hills and rivers near his home in a self-built helicopter.

He took design ideas from foreign websites, he said. "I downloaded pictures and looked at them again and again."

The amateur builders' experiments come at a time when China is pouring billions into its domestic aircraft industry in the hope of creating firms capable of competing with Western rivals such as Boeing and Airbus.

But Wang's flimsy-looking craft is more reminiscent of the biplanes flown by Feng Ru, an immigrant to the US who in 1909 became the first Chinese person to build a plane, using designs by the Wright brothers.

Feng met an untimely demise in 1912, when he crashed during a display after returning to China at the invitation of revolutionary leader Sun Yat-sen.

Wang has had near-misses of his own, his engine cutting out several times in mid-air, forcing him to glide down to earth.

"I told myself: there's no time to panic, just land!" he said of one near-death experience, adding cheerfully: "I once performed an emergency landing in a lake."