The main purpose of this legislation is to extend the deadline for commercial air tour operators in Grand Canyon National Park to upgrade their aircraft to quieter technology. This change aims to reduce noise pollution in the park, enhancing the experience for visitors and protecting the natural environment. The key provision of this legislation is the amendment of an existing law that originally required the conversion of air tour aircraft to quieter models within 15 years of the law's enactment. The new deadline set by this legislation is December 31, 2032.