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The point I was making that running a 6 volt motor from a 6V supply would probably use twice the current than running a 12V motor from a 12V supply (obviously with similar type motors). This would give twice the running time and also use smaller cables and possibly a lower cost ESC.

Regarding turning the Radar aerial have a look at the bottom of page 2 in http://members.aol.com/actionkit/prices.pdf