"As written, this bill puts our community under the authority of the FAA, which means the agency can, at any time, impose additional regulations on model aircraft. In addition, the bill specifically imposes a 400’ altitude limit on model aircraft operating within the programming of a community-based organization (CBO), which could potentially curtail long-standing AMA competitions and events that support local charities and non-profits." Source: AMA Government Relations Team, in a blog post concerning the FAA reauthorization act pending in Congress.