Howmet Aerospace makes engineered metal components for jet engines and airframes, including turbine blades and structural castings that have to withstand extreme heat and stress inside an operating aircraft engine. Its parts are used across both commercial aviation and defense programs, and the highly engineered, safety-critical nature of the work means customers rarely switch suppliers once a part has been designed into an aircraft program. Howmet was spun off from the former Alcoa as that company split its upstream aluminum production from its more specialized, higher-margin engineered products business. Demand for its parts tracks aircraft production rates and engine overhaul cycles, so an increase in commercial jet deliveries or defense spending tends to flow fairly directly into Howmet's order book.