Honeywell prepares to deploy F-35 power-thermal upgrade

The Royal Australian Air Force (RAAF) Lockheed Martin F-35As are scheduled to receive the TR-3 upgrade, which requires additional cooling for some of the aircraft's subsystems. This photo shows an RAAF F-35A with Japan Air Self-Defense Force (JASDF) Boeing-Mitsubishi F-15Js during Exercise ‘Bushido Guardian' in September 2023. (Commonwealth of Australia)

Honeywell is developing a cooling upgrade to its power and thermal management system (PTMS) to support avionics enhancements for the Lockheed Martin F-35 Lightning II fifth-generation fighter aircraft.

Matt Milas, president of Honeywell Aerospace's defence and space business unit, told Janes that an initial 2 kW PTMS upgrade will be rolled out in 2024 and will support the ‘Technology Refresh 3' (TR-3) standard and early Block 4 enhancements for the F-35. Australia is expected to be an early beneficiary of the upgrade. South Korea is also expected to receive the upgraded PTMS. On 13 September the US State Department announced a possible sale of up to 25 F-35As to South Korea. Janes earlier reported that these aircraft are very likely to be Block 4 aircraft, with acquisition to be completed by 2028.

The PTMS uses air pressure from the F-35's Pratt & Whitney F135 engine to cool the aircraft's heat-generating subsystems including some key avionics. The PTMS also supports the F-35's main engine start, cockpit conditioning, and provides emergency power. According to Honeywell, the existing PTMS can deliver 30 kW of cooling to the F-35.

However, cooling requirements on the aircraft are expected to increase as the F-35 adds new capabilities associated with TR-3 and Block 4. These capabilities include more powerful user-opted electronic warfare (EW) systems and other improved systems.