Any party to a proceeding other than the applicant and agency counsel may file comments about an application within 30 calendar days after it is served, or about an answer within 15 calendar days after it is served. A commenting party may not participate further in proceedings on the application unless the adjudicative officer determines that the public interest requires such participation in order to permit full exploration of matters raised in the comments.
14 C.F.R. § 1262.304