Aircraft Owners and Pilots Association
The Aircraft Owners and Pilots Association ( AOPA ) is a Frederick , Maryland-based American non-profit political organization that advocates for general aviation . 
<triplet> Aircraft Owners and Pilots Association <subj> Frederick, Maryland <obj> headquarters location <subj> American <obj> country <subj> non-profit <obj> instance of <subj> general aviation <obj> field of work <triplet> Frederick, Maryland <subj> American <obj> country