The Boeing B-29 Superfortress is a four-engine propeller-driven heavy bomber designed by Boeing and flown primarily by the United States during World War II and the Korean War. The Superfortress was designed for the high-altitude strategic bombing but also excelled in low-altitude night incendiary bombing. B-29s also dropped the atomic bombs on Hiroshima and Nagasaki.
Almost 4000 B-29 bombers were built, with the aircraft having been ordered into mass production even before their development was complete due to their unique capabilities.
The bomber’s capabilities were so highly prized that the Soviet Union had actively sought to acquire it from the United States under Lend-Lease during the Second World War, but had been denied this platform in order to protect the highly sensitive and unique American technologies which had been integrated.
The USSR managed to obtain three Superfortress bombers in 1944. The USSR went on to reverse engineer the bomber, and within three years the Tu-4 – a near exact replica of the platform – made its first flight in May 1947.
The bomber entered service in 1949 with almost 850 being built. The demonstrated vulnerability of the American B-29 against modern jet aircraft, namely the Soviet MiG-15, over the skies of Korea from 1951, made both the Superfortress and its Soviet derivative appear increasingly obsolete.
The Tu-4 thus began to be phased out of service in favour of the Tu-16 theatre bomber, with the intercontinental range Tu-95 being developed in parallel.
Before its decommissioning, however, the USSR provided the People’s Republic of China with over a dozen of the aircraft in an attempt to deter the United States from extending the air campaign over Korea northwards. The bombers remained in Chinese service until 1988
China’s Tu-4 fleet saw little active service, with the H-6 demonstrating far superior capabilities and used to carry out the country’s first nuclear test.
The People’s Liberation Army (PLA) did, however, attempt to modify the aircraft into an airborne early warning and control system (AWACS) to counter the American E-2 Hawkeye and E-3 Sentry.
In 1969 a single Tu-4 was thus modified to mount a Type 843 rotodome, with the resulting prototype names KJ-1.
The KJ-1 is a first generation Chinese AEW (Airborne Early Warning) radar fitted to a Tupolev Tu-4 bomber. The project was started in 1969 under the code name “Project 926”.
The Project 926 reportedly failed with the radar experiencing excessive clutter which undermined its viability as a force multiplier for the Chinese combat fleet.
According to PLA reports, the K-1’s value would have been equivalent to forty ground-based radar stations – and Chinese understanding of the importance and high value of AWACS in modern aerial combat spurred investment in obtaining such capabilities.
The development was stopped due to the Cultural Revolution. In the era of the Chinese economic reform, the project was once again put on hold because economic development was given top priority.
When the project was finally reviewed again for the modernisation of the People’s Liberation Army Air Force it was considered obsolete. In the KJ-1’s place, PRC developed a new phased-array radar for its KJ-2000 AWACS.
The sole KJ-1 is now on display at the PLAAF museum north of Beijing.