Honeywell 131-9B Auxiliary Power Unit, Gas Turbine Engine Outline

The 131-9B Auxiliary Power Unit features a high-efficiency mode upgrade that supports airlines in achieving greater fuel efficiency, reduced carbon emissions, and improved time on wing. The APU operates with dual functionality, serving as both a starter and a generator. It uses electrical power to start itself and then acts as a generator to power the aircrafts systems. The two-stage axial turbine design contributes to a longer engine life. The combination of advanced hardware and software delivers HEM benefits that enhance operational and bottom-line performance for operators. The redesigned diffuser is critical, and the software autonomously controls the diffuser to regulate airflow into the compressor section, allowing the engine to burn fuel more efficiently at lower temperatures, which reduces wear and tear on critical engine parts. It also reduces overall maintenance costs and lowers spare parts requirements due to longer time-on-wing.