<page_title> Lockheed A-12 </page_title> <section_title> M-21 </section_title> <table> <cell> 60-6924 <col_header> Serial number </col_header> </cell> <cell> A-12 <col_header> Model </col_header> </cell> </table>
Lockheed A-12 serial number was 60-6924.