After American Airlines, United optimistic about 737 MAX fixture

United Airlines, one of three U.S. carriers that operate Boeing's 737 MAX, is "optimistic" about the U.S. manufacturer's software update, Vice President of Corporate Safety Michael Quiello said in a statement on Wednesday.

"But, the U.S. commercial aviation system is the safest in the world because its foundation is built on rigorous data analysis and evidence-based independent oversight, and we look to the FAA to employ these tools as it reviews and certifies this software update," Quiello added.