GAMA is questioning some of the Environmental Protection Agency’s data used in developing an endangerment proposal on aircraft emissions, but recognized the need for the finding to pursue regulation in concert with international efforts. In comments on the EPA’s proposed endangerment finding and advanced notice of proposed rulemaking exploring possible new regulation of aircraft emissions, GAMA said the association “strongly supports the development of an international aircraft CO₂ emission standard at ICAO.” The association added it further understands that the endangerment finding is a requisite step in the development of U.S. regulation.

But GAMA questioned the EPA’s use of inconsistent data sources “to portray aviation emissions, past, present and forecast in the worst possible light, while barely acknowledging the significant efficiency improvements in aviation to date.” GAMA noted that the EPA publishes complete and consistent data on U.S. greenhouse gas emissions, but uses outside sources for justification.

GAMA also noted that since a number of issues have yet to be decided by ICAO, it would be premature to address issues such as whether standards should apply to in-production aircraft instead of new types only. The association stressed, “It is absolutely essential that the U.S. allow the international community to complete its work.” GAMA expressed concern about EPA’s query on whether it should “go it alone” and impose a unilateral CO₂ standard. “Nothing could be worse for the health and vitality for the U.S. aviation industry,” the association said.