studies The Secretary of Transportation may implement the policy set forth in the notice of proposed policy titled Proposal to Consider the Impact of One Engine Inoperative Procedures in Obstruction Evaluation Aeronautical Studies published by the Department of Transportation on April 28, 2014 (79 Fed. Reg. 23300), only if the policy is adopted pursuant to a notice and comment rulemaking and, for purposes of Executive Order 12866 ( 5 U.S.C. 601 note