The KJ-600 is the Chinese Navy’s future carrier-based airborne early warning and control
aircraft, or AEWAC for short. Once it enters service, it will act as a long-range detector
and a mobile command centre for Chinese carrier air forces. The KJ-600 first flew in mid-2020. At
least six airframes are in various stages of testing. Most of these are flying prototypes
serving various roles, although at least one of these is likely to be a static airframe for land
testing. Amid the increasing frequency of flight test over the years, the KJ-600 is likely to be
on the verge of low-rate initial production, which would fit together with the fitting out,
and anticipated sea trials and aviation trials in the near future of China’s
newest aircraft carrier, the Type 003 Fujian. As of mid-2023, the Fujian is China’s only
carrier with aircraft catapults, otherwise known as a CATOBAR carrier, which stands for catapult
assisted take-off barrier arrested recovery. Additional CATOBAR carriers are expected to be
built in the coming years, even if the timeline for their production is unknown at this stage.
China’s People’s Liberation Army Navy, or the PLAN, also has two ski-jump aircraft carriers,
which do not have catapults. One of the benefits of the Fujian’s
catapult is the ability to launch a wider variety of different aircraft under a greater
range of conditions than the ski-jump carriers. Consequently, the Type 003 Fujian's air wing
will be far more diverse than its predecessors and will include J-35 stealth fighter jets as
well as a catapult-enabled variant of the J-15 Flying Shark. A key component of this airwing,
also made possible by the Fujian’s catapults, is the KJ-600 airborne early warning and control
aircraft, or AEWAC for short. The AEWAC is one of the most important force multipliers
for a modern air force, and a fixed-wing version operating from a carrier is far more capable than
a helicopter equivalent operating in the same place. At present, the world’s only fixed-wing
carrier-based AEWAC in service is the E-2 Hawkeye, developed by the U.S. company Northrop Grumman. It
is operated by the U.S. Navy and several other navies, including that of Japan and France.
China is developing this critical technology for its naval air forces with the KJ-600.
Since the Chinese AEWAC has not yet entered service, actual footages are rare,
so we will mainly be showing the US Navy’s E-2 Hawkeye that serve a similar function.
In terms of the role that the KJ-600 will play in the future air wing of the Fujian,
it will be there to dramatically extend the carrier’s radar range, especially when it comes
to spotting low-flying objects or even surface warships. So, this means improved battlespace and
battlefield awareness for both carrier airwing and the carrier taskforce itself. It will also
serve as a battlespace manager. Controllers onboard the KJ-600 will direct aircraft as
needed and sustain a mobile command and control centre for highly coordinated missions. Data
provided by the KJ-600's radar signals and other passive sensors will be linked back to
other aircraft and surface warships, to become real-time information they can use. Another
possibility is that the KJ-600 can function as a central data-fusion and rebroadcasting node for
a wider system of systems in integrated warfare. Based on satellite photos, the KJ-600 has extended
wingspan of 24.4 meters and a length of 18.4 m, which is comparable to the E-2, and consistent
with the need for compactness of a carrier-based aircraft. It has a configuration similar to the
E-2 family, which is not a surprise given that both planes essentially serve the same function.
The KJ-600 has a high-wing design, where wings are mounted on the upper fuselage. It
is powered by two turboprop engines. An aerial refuelling probe has not been seen as of yet,
but could be added in the future to extend mission radius and endurance. A rotating radar dome,
or rotodome, is mounted above the fuselage. Total crew number for the KJ-600 is expected
to be at least five, with a pilot, a copilot, and at least three mission console operators.
The turboprop engines are the six-bladed WJ-6C, the same turboprop that has powered Y-9 transport,
anti-submarine and electronic warfare aircraft. A catapult launch bar on the
nose landing gear confirms the KJ-600 is intended for launch from a CATOBAR carrier.
A rear Y-shaped recess in the rear fuselage and what appears to be part of a tailhook point to
the presence of a Y-shaped tailhook for arrested recovery. Wing fold lines appear to be present in
past photos, pointing to foldable wings to save space on carrier deck and hangars. There has been
so far no visual evidence to suggest that KJ-600 has undergone catapult launch or arrested landing
tests from land-based naval catapult test sites, which the Chinese Navy has available. However,
the key features seen in past photos strongly alludes to the plane’s carrier purpose.
It is also highly possible that catapult testing have occurred without being captured on film
or photos, which is totally plausible given the high degree of PLA operational secrecy.
The KJ-600’s primary radar remains unknown, but it is certainly to be an active electronically
scanned array, or AESA for short, which is the leading standard for air search radar
systems used by the military. AESA radar is already a mature technology for the Chinese
military industrial complex. It is already in use on China’s air warfare destroyers,
and 4.5 and fifth generation fighters. The radar’s frequency band is likely to be S or L band,
which is fairly standard for AEWAC, and would fulfil the air search function well. The KJ-600’s
rotodome radar appears to be a single-sided array. A rotodome radar configuration with a single-sided
array is different from the three-sided radar dome seen on other Chinese AEWAC,
with three radar arrays, like the KJ-500 and the KJ-2000. This may reflect an emphasis on the
size of array and therefore the sensitivity of the array over the benefit of 360-degree surveillance.
The US Navy’s E-2 Hawkeye also uses a rotating single sided array. The KJ-600’s radar system
and avionics are likely to be the most recent and most advanced the Chinese industry has to offer,
keeping in mind that Chinese radar technology has made vast progress in terms of materials and
software over the last decade. In addition to the primary rotodome radar, a large nose radome points
to the presence of a nose radar of some sort. The outward similarity between the KJ-600 and
the E-2 Hawkeye is undeniable. There have been insinuations or even claims in the Western defence
media that the KJ-600 is reverse-engineered or even copied from the E-2. Much of these
claims arise from the very similar airframe and subsystems of the two aircraft. There are obvious
differences in key external features, including in the shape of the fuselage, tail configuration,
nose geometry, landing gear, and small differences in overall dimensions. The combination of these
differences makes it highly unlikely that the KJ-600 was reverse engineered, or copied, from the
E-2. The KJ-600 is likely to be influenced by the design of the E-2, but only at a surface level.
Given the similarity in mission requirement between the KJ-600 and the E-2, it is likely
the optimal basic designs for the two planes would be similar, even if both designers tried
their best to customise their design for the needs of their own forces. You can see the
same pattern in stealth fighter design globally, with the US F-22 and F-35, the Chinese J-35 and
the Korean KF-21 all sharing similar basic features to achieve stealth requirements.
We know the PLA Navy prefers mature and proven systems with low risk,
as opposed to revolutionary systems with a high risk of delays and failure. As such,
the basic airframe and configuration are based on the most widely used, and the
most successful over the past decades, which is that of the E-2 and the proposed Soviet Yak-44.
It is the option that carries the lowest risk. Nevertheless, pursuing a mature configuration
would still necessitate the clean-sheet design of the engines, the landing gear, the arresting gear,
the internal space and the cockpit. To say nothing of the necessary development of the radar, passive
sensors, mission consoles, datalinks and flight controls. So, while the KJ-600 may be influenced
by the E-2, there is only so much insight from observing the exterior of a mature airframe.
You still have to make everything on the airframe and inside the airframe yourself.
A number of development milestones remain for the KJ-600. These include land-based launches from
catapults and land-based arrested landing. After that, the next major tests will be carrier-based
catapult launches and carrier-based arrested recovery. These achievements will depend on
the Fujian aircraft carrier achieving sufficient readiness for sea trials and aviation trials in
time. The KJ-600 is not believed to able to launch from the ski-jump of the PLAN’s STOBAR carriers,
the Liaoning and the Shandong. It may be too heavy to take-off using its own power even with a ski
jump. However, the possibility of deploying the KJ-600 on the STOBAR carriers, and potentially
launching them with a reduced payload of fuel, cannot be ruled out at this stage.
The entry into service of the KJ-600 could occur around the same time as the commissioning of the
Fujian, or even preceding it a little bit. The acceptance of the KJ-600 sometime before
commissioning of the Fujian would allow for pilot and crew training to begin early.
This would reduce the downtime before the Fujian becomes ready for combat. The KJ-600,
the J-35 and the catapult-capable J-15 fighters are well on the way to forming the airwing of
China’s Type 003 Fujian aircraft carrier. China’s naval aviation capability will be due for a huge
uplift in the next few years, at least in terms of quality. The increase in quantity on the other
hand will require additional CATOBAR carriers, and greater production of carrier-based aircraft.