CH-4

The CH-4, also written Cai Hong 4 or Rainbow 4, is a medium-altitude, long-endurance unmanned combat aerial vehicle developed by the China Academy of Aerospace Aerodynamics, part of the China Aerospace Science and Technology Corporation (CASC). It first flew in 2014 and is now in service with more than a dozen militaries, making it one of the most widely exported Chinese armed drones. Its outline closely resembles the General Atomics MQ-9 Reaper, apart from the CH-4's lack of a ventral fin.

Design and capabilities

CASC gives the CH-4 a length of 8.5 m and a wingspan of 18 m, with a maximum take-off weight of about 1,300 kg carried on a single piston engine of roughly 100 hp driving a rear-mounted pusher propeller. The aircraft can carry up to 345 kg of payload and is rated for a service ceiling of about 8,000 m and a maximum speed of 435 km/h, with a cruise speed around 330 km/h. CASC has quoted an endurance of up to 40 hours and a maximum range of 3,500 km in its reconnaissance configuration; its line-of-sight control range is about 150 km from a ground control station, extendable beyond 1,000 km over a satellite communications link.

Two main variants are flown: the CH-4A, optimised for reconnaissance, and the CH-4B, which adds hardpoints for up to six guided weapons alongside its sensors, including air-to-surface and anti-tank missiles and small guided bombs, for a combined reconnaissance-and-strike role.

Operational history

Iraq received its first CH-4s by 2015 and used them against Islamic State forces during 2013-2017, though Iraqi aircraft were later put into storage and reported maintenance problems. The Saudi-led coalition has flown CH-4s, operated by both Saudi Arabia and the United Arab Emirates, over Yemen; more than a dozen Saudi CH-4s had been lost by mid-2022. Other operators include China's own PLA Ground Force, Algeria, Armenia, the Democratic Republic of the Congo, Ethiopia, Indonesia, Myanmar (which builds the type under licence), Pakistan, Sudan and Zambia. The CH-4 is part of a wider Rainbow family that includes the smaller CH-3 and the larger CH-5.

Frequently asked questions

What is the range of the CH-4?

CASC has quoted a maximum range of about 3,500 km for the reconnaissance-optimised CH-4A, separate from its roughly 150 km line-of-sight control range and its satellite-relayed control range of over 1,000 km.

Can the CH-4 carry weapons?

The CH-4B variant can carry up to six guided weapons, including air-to-surface and anti-tank missiles and small precision-guided bombs, alongside its sensors.

Who operates the CH-4?

More than a dozen militaries, including China's own forces, Pakistan, Saudi Arabia, the United Arab Emirates, Iraq, Indonesia and several African states.

How is the CH-4 different from the CH-3 and CH-5?

The CH-3 is a smaller, shorter-range medium UAV in the same family, while the CH-5 is a larger, longer-endurance successor design.