fuel flow channels used. Inherent safety Because a bell-type expander-cycle engine is thrust limited, it can easily be designed to withstand its maximum thrust conditions. In other engine types, a stuck fuel valve or similar problem can lead to engine thrust spiraling out of control due to unintended feedback systems. Other engine types require complex mechanical or electronic controllers to ensure this does not happen. Expander cycles are by design incapable of malfunctioning that way. Usage Expander cycle engines include the following: Aerojet Rocketdyne RL10 Pratt & Whitney RL60 ArianeGroup Vinci CADB & Pratt & Whitney RD-0146 Chinese YF-75D Mitsubishi Heavy Industries LE-5A / 5B Mitsubishi Heavy Industries LE-9 Aerojet Rocketdyne & MHI MARC-60 (MB-60) Blue Origin BE-3U and BE-7 Avio M10 Comparison of upper-stage expander-cycle engines See also Gas-generator cycle Combustion tap-off cycle Staged combustion cycle Pressure-fed engine References External links Rocket power cycles Rocket propulsion Rocket engines Spacecraft propulsion Engineering thermodynamics