Chengdu Aircraft (CAC) of China is trying to further refine the performance of the venerable Mikoyan MiG- 21/F-7 fighter design with a newly unveiled technology demonstrator sporting a radically reshaped nose section with a chin air intake and ogival radar housing.
The heavily modified F-7FS testbed is based on the earlier F-7II, but has a chin air intake with splitter in place of the original conical nose inlet. According to CAC sources, the larger-volume intake has permitted the installation of an uprated 73-78kN (16,500-17,600lb)-thrust turbojet developed from the Wopen WP13F.
Reconfiguration of the nose inlet has allowed CAC to redesign the F-7's extremely confined radar bay and radome. The F-7FS nose is large enough to accommodate a new, locally developed 600mm-diameter multi-mode pulse-Doppler radar, says CAC. This replaces earlier ranging radars, such as the GEC-Marconi Type 226 Skyranger in the F-7M and Chinese JL-7 fitted to the F-7III.
The F-7FS will be used primarily as a flying testbed for new radar and avionics systems, such as weapon management, global positioning systems and flight data recording systems. Sources suggest that the aircraft will be used to flight-test a yet-to-be-selected avionics and radar package for the planned Sino-Pakistani CACFC-1. The reconfigured F-7 flew for the first time last month, kicking off a 22-month test programme.
Further modifications are planned to be tested on the F-7FS airframe, including a future redesign of the aircraft's delta wing. The change is intended to build on the improved double-delta wing design of the last improved production variant unveiled in 1996, the F-7MG.
Source: Flight International
