The Chinese Government has been accused of numerous military-industrial cyber-attacks against the US, the direct effects of which are almost impossible to gauge. The contentious case of China’s J-31 'Shenyang' stealth fighter, formally unveiled at the Zhuhai Air Show last week, might turn out to be a fascinating exception to this rule.

Put bluntly, the J-31 bears an unmistakable similarity to the pioneering F-35 US stealth fighter, and there don’t appear to be many experts who doubt that the later Chinese machine is a direct copy from its eerily-identical silhouette to many of its surface details.

Chinese J31 Stealth Fighter source Chinese Ministry of Defence 800x450

Copying in this case is an insincere form of flattery because, it is claimed, the Chinese got hold of the blueprints to build the J-35 during a cyber-espionage attack on Lockheed Martin dating back at to 2009, or possibly earlier.  In 2013, during a senate sub-committee hearing the US Government admitted that the F-35 plans and many other projects had been pilfered, although China wasn’t mentioned as the perpetrator.

This wasn’t a classic case of cyber-espionage – most of the plans are believed to have been siphoned off and sold by an insider working for a contractor rather than an external hack – but the end result is the same. The US defence industry now look like clots for allowing the secrets behind one of their most advanced aircraft designs to slip into the hands of the country’s superpower rival. If such a thing had happened during the Cold War, it’s hard not far-fetched to think that it would have engendered a major crisis.

Ironically, while during the Cold War, both sides devoted huge efforts to gathering intelligence of this kind they were secretive about letting the enemy know that a compromise had happened. The idea of the Soviets building an obvious replica of a US aircraft type would have been unthinkable, not least because it would have implied that its own engineers were behind the US.

The exception was possibly the ill-fated TU-144, a 1970's supersonic Soviet jet airliner meant to rival the Anglo-French Concorde, which many people to this day believe were too similar to one another for that to be a coincidence. Whatever the truth, underneath the skin they turned out to be very different machines and that perhaps is a pointer to the moral of the J-31 story.

Assuming the Chinese did base the J-31 on the F-35’s airframe that doesn’t mean that their knock-off is the same aircraft. The engines will be different, as will the materials, avionics, pilot systems, manufacturing and testing data. As the world’s terrorist Ghostbusters, the US pilots also get to use their machines more often these days. At 35,000 feet, a duel depends on small differences and you’d bet heavily on the US aircraft having the edge.

The Chinese don’t seem to care that the US knows that it is building a military aircraft industry on the back of their ideas, indeed they seem to revel in pointing this out as a symbolic humiliation. Perhaps this is unwise. If the J-31 really does fly like an F-35 there is only one nation that will know what compromises were made to get it into the air and what small hidden weaknesses may lurk inside its specification.

Industrial espionage and cyber-hacking are all very well but they don’t necessarily translate into a real-world advantage if executed in a clumsy way. Personally I think the proud, wily Soviets were far more sophisticated. Build your own stuff, preserve the engineering mystique and always beware the notion that 'catching up' is the same as 'being in the lead'.