China has for long been trying to develop stealth technology for its fighter aircraft, and the end results have been questioned by experts.
However, the Asian giant seems to be taking the problem in a manner
that's totally different from how the West, particularly the US. The
Chinese are trying to develop materials that when used to cloak
aircraft, can even make older non-stealth aircraft nearly invisible.
Reports in Chinese
media have referred to it as the 'cloak of invisibility'. This approach is different from the Western methods of
relying on stealthy airframes and surfaces for the aircraft. It will
rely on 'metamaterials' to either absorb or deflect radio waves,
theoretically making the aircraft invisible on command.
The news is likely to gain sustained interest and analysis in
defence circles because it would help turn much older aircraft into stealth
variants.
Stealth technology is not a single unit of technical know-how. It is
more of a collection of design principles and material usage that helps
an aircraft or a ship minimise its radar cross-section. That means a
massive craft will show up as a much smaller object when it is picked up
by a radar. The very idea of stealth is aimed at giving fighter jets
more time before they are detected, cutting down on the reaction time
available to the adversary.
For instance, the Lockheed Martin F-22 Raptor, considered the pinnacle
of stealth technology so far, has wings that stretch 13.56 meters from
tip to tip. But it will be detected by radar as an object that's the
size of a steel marble, according to some estimates. The technologies
and radar-absorbent materials developed for the F-22 are presently
available only to the US, and that's why the manufacturer is banned from
selling the F-22 to anyone other than the US military.
The Chinese have claimed that their bid at building a stealth fighter -
the Chengdu J-20 - has been successful. But defence experts have raised
doubts on what they point out are design elements that are fundamentally
anti-stealth - like the J-20's canards.
The Chinese are now testing the metamaterial 'cloak of invisibility' on
non-stealth aircraft at a testing facility near Eastern China's
Shenyang, Chinese media have reported. The metamaterials used were
developed at the State Key Laboratory of Millimetre Waves at Nanjing's
Southeast University.
The 'metamaterial' is a layer that features microscopic structures
similar to integrated circuits. The metamaterial can alter the way radio
waves bounce off its surface to create a ghost image or minimise echo
on a radar.
However, the reports did note that there are significant difficulties to
be surmounted before the technology can come to fruition. The team
developing the material had said in 2011 that it could absorb the three
most commonly used military radar waves. In 2013, they claimed to have
developed a 'ghost illusion device' that render the aircraft with almost
no radar signature.
But 'metamaterials' alone would not be enough to equip an aircraft with
stealth. It would only be a piece of the puzzle. Metamaterials are also
difficult to mass-produce, placing crushing curbs on their widespread
use.
Either way, the Chinese may be doing the same things the Americans did,
but time will tell whether their difference in approach will help them
reach an innovative result that the world has not seen yet.