BAE Systems AN/ASQ-239

History

BAE Systems developed the AN/ASQ-239 electronic warfare suite as part of the F-35 Lightning II program, building on more than 60 years of electronic warfare experience that began with radar defense technology in the 1950s. The company's countermeasure heritage progressed through U.S. carrier-based aircraft in the Vietnam War era and the F-22 Raptor before culminating in the AN/ASQ-239 for the F-35. BAE Systems serves as the design, production, and sustainment provider for the system.

In October 2026, BAE Systems received a contract from Lockheed Martin to manufacture and deliver AN/ASQ-239 systems for F-35 production Lots 20 through 22, along with retrofit and modernization systems for earlier-aircraft builds. The Digital Channelized Receiver Techniques Generator and Tuner Insertion Program (DTIP) previously delivered the system's existing functionality in a smaller footprint, reducing volume and power requirements and creating space for future F-35 modernization. Production is supported from BAE Systems facilities in Austin, Texas, and Manchester, Merrimack, and Nashua, New Hampshire.

Design

The AN/ASQ-239 is a fully integrated, digital electronic warfare and countermeasures suite that collects and processes electromagnetic energy across a 360-degree field of view. It provides broadband radar warning, targeting support, geolocation of electronic emitters, and self-protection. The system is designed as a platform-level solution with a modular, scalable, open-system architecture intended to reduce long-term life-cycle costs. It is always active and provides all-aspect, broadband protection.

Key hardware elements include an Aperture Rack, a Countermeasures Controller (CMC), two equipment racks (2A and 2B), and Countermeasures Canister Dispensers. The system provides both radio-frequency and infrared countermeasures with rapid-response capability. It is capable of simultaneous jamming without interference to the F-35's radar or radar warning receiver, allowing the aircraft to operate in signal-dense environments and reach well-defended targets.

Sensor fusion integration

The AN/ASQ-239 contributes emitter tracks to the F-35's sensor-fusion function, which combines electronic warfare track reports with data from the AN/APG-81 active electronically scanned array radar and the Distributed Aperture System. The fused information is presented to the pilot, providing options to evade, engage, counter, or jam identified threats. The AN/ASQ-239 operates alongside the AN/APG-81, which itself incorporates electronic protection, electronic attack, and electronic support measures, reflecting the integration of radar and EW functions within the F-35 mission-systems architecture.