A possible prototype image of China's future H-20 bomber

The Chinese Air Force operates the Xian H-6K, a Chinese license-built version of the Soviet Tupolev Tu-16 bomber

China's new generation strategic bomber is likely to be ready for delivery this year, but Beijing is said to be weighing the impact of its unveiling at a complex time in regional relations due to the Coronavirus pandemic.

Military sources said the Xian H-20 supersonic stealth bomber — expected to double the country's strike range — could make its first public appearance at this year's Zhuhai Air Show in November, if the pandemic was sufficiently under control.

"The Zhuhai Air Show is expected to become a platform to promote China's image and its success in pandemic control — telling the outside world that the contagion did not have any big impacts on Chinese defence industry enterprises," a source said.

But the appearance of the bomber at this year's air show could heighten tensions by directly threatening countries within its strike range, especially Australia, Japan and the Korean peninsula.

"The Beijing leadership is still carefully considering whether its commission will affect regional balance, especially as regional tensions have been escalating over the Covid-19 pandemic," another source said.

"Like intercontinental ballistic missiles, all strategic bombers can be used for delivering nuclear weapons … if China claimed it had pursued a national defence policy which is purely defensive in nature, why would it need such an offensive weapon?"

Tensions in the region have worsened in the past month with a war of words between Beijing and Washington over the pandemic, and both sides increasing naval patrols of the Taiwan Strait and South and East China seas.

The US defence department has estimated a cruising distance of more than 8,500km (5,300 miles) for the H-20, the last in China's 20 series of new generation warplanes, which includes the J-20 stealth fighter jet, the Y-20 giant transporter and the Z-20 medium-lift utility helicopter.

The arrival of the H-20 would mark the completion of China's "nuclear triad" of ground-based intercontinental ballistic missiles, submarine-launched missiles and air-launched weapons.

Chinese state television has said the H-20 could alter the strategic calculus between the US and China by doubling the strike range of its current H-6K, dubbed the country's B-52.

The H-20 has reportedly been designed to strike targets beyond the second island ring — which includes US bases in Japan, Guam, the Philippines and other countries — from bases in mainland China. The third island chain extends to Hawaii and coastal Australia.

It will be equipped with nuclear and conventional missiles with a maximum take-off weight of at least 200 tonnes and a payload of up to 45 tonnes. The bomber is expected to fly at subsonic speeds and could potentially unleash four powerful hypersonic stealth cruise missiles.

However, like China's first active stealth fighter jet, the J-20, engine development of the H-20 bomber has fallen behind schedule, according to sources.

For the J-20, engineers were developing high-thrust turbofan WS-15 engines, but the jet is understood to be using either Chinese WS-10B or Russian-built AL-31FM2/3 engines, which compromise its manoeuvrability and stealth capabilities at subsonic speeds.

Military enthusiasts have speculated the H-20 might use the NK-321 Russian engine but two independent military sources said it would be equipped with an upgraded WS-10 engine.

"The WS-10 is still a transitional engine for the H-20 because it is not powerful enough. The eligible replacement may take two to three years for development," one of the sources said.

The second said the speed of the H-20 would be slower than its original design, with some of its original combat capability being reduced.

"That's why the American air force doesn't care about the H-20, because it is not strong and powerful enough to cause any challenge to their B-2 and B-21 bombers."

If the US decided to deploy more F-35 supersonic fighter jets — it has already sold about 200 to Japan and South Korea — it could push China to bring forward the unveiling of the new bomber, the second source said.

"For example, if some US decision makers decided to deploy up to 500 F-35s to Japan, South Korea, and even Singapore, India and Taiwan — making almost all of China's neighbours in the Indo-Pacific region use F-35s to contain China — that would push Beijing to launch the H-20 as soon as possible."

The H-20 is believed to have been in development since the early 2000s. The project to develop a strategic bomber was first announced by the People's Liberation Army in 2016.