PHOENIX — Honeywell Aerospace in Phoenix, Arizona, has introduced an upgrade to the F-35's power and thermal management system (PTMS) that the company says will boost cooling capacity by 25% without requiring changes to the aircraft's structure.
The P40 upgrade raises the system's cooling capacity from approximately 32 to 40 kilowatts through software changes and targeted improvements to its liquid-cooling equipment. Honeywell expects to field the technology between 2029 and 2030.
The F-35's sensors, mission systems and onboard computers generate heat that the aircraft must remove to keep its equipment operating within acceptable temperature limits. As operators add new capabilities, they also increase the demand on the aircraft's cooling system.
Honeywell designed P40 to work within the existing PTMS architecture. The company says operators can install the upgrade alongside the F-35's planned Engine Core Upgrade, allowing them to add cooling capacity during scheduled maintenance rather than make separate airframe modifications.
“Operators need additional cooling capacity and improved readiness on a timeline that matters,” said Matt Milas, president of Defense and Space at Honeywell Aerospace. “P40 delivers both by building on the proven PTMS architecture already operating across the global F-35 fleet.”
Related: Honeywell develops F-35 power and thermal management upgrades
Increasing cooling capacity within the existing system
The F-35's PTMS handles 14 functions, including auxiliary and emergency power. Replacing a system with so many roles would require redesign, integration and qualification work before operators could introduce it across the fleet.
P40 instead modifies equipment already in service. Honeywell says operators can add cooling capacity while continuing to use their existing maintenance facilities and technical expertise.
The company also plans to increase the system's capability in stages. It says the existing architecture could eventually support 62 kilowatts or more, although it has not announced a fielding schedule for that level of cooling.
Honeywell targets fewer in-flight shutdowns
Honeywell and the aircraft's original equipment manufacturer analyzed nearly 1 million fleet flight hours to investigate non-resettable in-flight shutdowns attributed to Honeywell equipment. They identified the causes of those events and developed corrective actions for P40.
Honeywell projects that the changes will reduce Honeywell-attributable non-resettable in-flight shutdowns by approximately 30%. The company is pursuing additional reliability improvements to minimize maintenance demands across the fleet.
