The Soviet Union’s Antonov An-225 was designed to transport the Buran space shuttle. It still flies sporadically today – but a Chinese plan could give it a new lease of life.

Tucked away in a small section of a Soviet era air base on the outskirts of Kiev is the flagship aircraft of the legendary Antonov design bureau. A one-off masterpiece of engineering designed and built during the 1980s in the waning days of the USSR.

The aircraft, designated the An-225, is the biggest to ever grace the Earth. It’s so large that the length of its cargo hold is longer than the Wright brothers’ first flight, from take-off to landing.

Now 30 years old, and recently upgraded to give it another 20 years’ service, the plane rarely takes to the skies anymore. Instead, it sits stagnant under an enormous steel arch. However, a crew of dedicated Antonov employees still periodically tend to the An-225. Its sporadic use has nothing to do with its age. It’s grounded because there is simply little demand for its highly specialised and relatively costly service. Although the plane, nicknamed ‘Mriya’ (‘Dream’) in Ukrainian, is in fine condition, there are very few jobs that call for something so large . And the jobs need to be urgent; if you want to use the An-225 it will cost around $30,000 (£23,220) an hour.

In 2016, it spent just three months traversing the globe on two lengthy deployments. The remainder of the time, it sat here at the Gostomel airport, once a top-secret flight testing airfield for Antonov.

Originally built as a transport for the Soviet Union’s Buran space shuttle, the An-225 was forced to find new purpose as a cargo carrier after the USSR collapsed, says Alexander Galunenko, the first man to fly the plane.

“When the USSR collapsed, the programme was shut down and the financing was closed as the need for this plane vanished,” says Galunenko. He first flew the An-225 on 21 December 1988, after over a decade’s service as a Soviet test pilot.

Galunenko fondly remembers the bewilderment of first taking the behemoth across the world to visit the United States.

We got to show our plane and give the Americans a geography lesson too - Alexander Galunenko, An-225 test pilot  

“We were invited to an aviation show in Oklahoma and the media reported that the largest aircraft in the world was coming so that attracted a mass of people,” he says.All of these people just assumed that the largest aircraft in the world was made by the Boeing company. We had to tell them it was made by Antonov, and they asked, ‘Where is Antonov from?’ We said, ‘It’s a company in Kiev’, so they asked us, ‘And what is Kiev?’ Well we told them ‘Kiev is in Ukraine’, and of course they asked, ‘But what is Ukraine?’”

The navigator of the flight eventually pulled out his maps and began to point out Ukraine to the many curious visitors. “He took a marker and circled Kiev to show them where it is,” laughs Galunenko. “We got to show our plane and give the Americans a geography lesson too.”

The plane is effectively an extension of its little brother, the An-124 ‘Ruslan’ – an aircraft rarely regarded as “little”, seeing as it’s the largest military transport in the world.

From a room adorned with scale models of every aircraft the company has built in its 71-year history, the lead engineer of the An-225 project, Nikolay Kalashnikov, tells BBC Future that he spent his entire professional life working for Antonov. But it was building the Mriya that was the pinnacle of his career.

“Today it's hard to tell, but back then it was so impressive. It was just so difficult to imagine that such a big machine can fly,” says Kalashnikov.

Although the An-124 Ruslan was already an impressively sized cargo carrier at that time, Kalashnikov and his team set about modifying the structure to increase its maximum takeoff weight. They added two engines, rows of landing gear, extended the fuselage and redesigned the tail in order to meet the most important requirement, to ensure that the Buran space-shuttle could be carried.

The skies could soon be flooded by a fleet of Chinese built An-225s  

At that time, the USSR’s space missions were run from what is now southern Kazakhstan, at the Baikonur Cosmodrome. So the AN-225’s mission was to bring the booster rockets from Moscow and ferry the Buran itself to Baikonaur. They calculated that the AN-225 programme would be cheaper than building a freeway across two rivers and through the Urals just to move these parts, says Kalashnikov.

Anotonov's CEO Mikhail Kharchenko believes that the Mriya still has huge potential, despite its age, and it’s not just for its enormous cargo capacity. He thinks there’s still the chance to develop the An-225 into a proper in-air launch platform.

“Approximately 90% of the energy of the launch vehicle is spent getting up to an altitude of 10km (6.5 miles) ,” says the CEO. “If we take some spacecraft and put it on the Mriya's back and fly it up to a height of 10km, then we can launch it into space from there. From the point of view of cost, the economic benefit is huge if you launch from a height of 10km.”

He admits it’s still going to take a little bit of refinement, but Kharchenko believes this is the best direction for his company’s flagship aircraft. And he’s not the only one.

In 2016, the Airspace Industry Corporation of China (AICC), a privately-owned aerospace and defense company, signed a cooperation agreement with Antonov for the An-225 programme. If it goes through as planned, the skies could soon be flooded by a fleet of Chinese built An-225s.

“The initial idea and early stage research of the An-225 started in 2009,” the president of AICC, Zhang Youshengtells BBC Future. “The official contact with Antonov began in 2011, and then from 2013 to 2016 was the acceleration phase of this project.”

The Chinese company isn’t interested in purchasing the existing airworthy An-225. They have spent the past several years studying the feasibility of modernising the only other An-225, an unfinished airframe that has sat inside a hangar at Antonov’s giant corporate campus in downtown Kyiv for the past 30 years. This aircraft, when modernised, could give China a heavy lift capability that surpasses any other nation in the world – perhaps even greater than that of the US military.

The men who built the plane have mixed feelings about the prospect of losing the programme to the Chinese  

According to Zhang, the An-225 would be the centrepiece of a hyper ambitious plan to add 1,000 heavy lift aircraft over the next 10 years.

Heavy lift is not the only capability they’re after though.

“The An-225 can be equipped with spacecraft to high altitude, and can launch commercial satellites at any height below 12,000m,” Zhang tells the BBC. “Its launch time is flexible, accurate, and can quickly send the satellite into intended orbit, which greatly reduces launch costs.”

The Chinese are aiming to make their way into the lucrative satellite launch industry, which doubled revenue from 2006 to 2015, according to figures provided by AICC.

The purchase agreement for the existing An-225 airframe is similar to China’s acquisition of an aircraft carrier hull from Ukraine nearly 20 years ago. That hull, originally commissioned by the Soviet Union, was rebuilt and modernised over two decades until it was declared ‘combat ready’ by China’s military in November 2016.

If the plan goes forward, the Mriya will have found new life flying the skies for China’s AICC, but Ukraine will have lost of a small but symbolic part of its aerospace industry. The men who built the plane have mixed feelings about the prospect of losing the programme to the Chinese.

“The Chinese want to buy from us this plane and there's no harm in it, but of course no one wants to sell the aircraft,” says Kalashnikov. “The Mriya is not separable from Ukraine, it’s like our child, and it’s something our children, and our grandchildren can always be proud of.”

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