What propulsion system is used in the F-35?

The F-35 utilizes the Pratt and Whitney F135 turbofan engine as its propulsion system. This engine is specifically designed for the F-35, catering to its unique role as a stealth multirole fighter. The F135 engine boasts several advanced features including a high thrust-to-weight ratio, low observable technology, and the capability for vertical takeoff and landing in the F-35B variant. Additionally, the engine’s modular design facilitates maintenance and logistics support, ensuring operational efficiency for the aircraft.

In contrast, the other options mentioned are associated with different aircraft or do not align with the F-35's design. The General Electric F119, while a notable engine used in the F-22 Raptor, does not power the F-35. Likewise, the Rolls-Royce F136 was proposed for the Joint Strike Fighter but was eventually not selected. The Honeywell F109 is primarily used in rotorcraft, such as helicopters, and has no connection to the F-35’s propulsion system.