<Tr> <Th> NATO Code </Th> <Th> Aus / US Code </Th> <Th> Navy </Th> <Th> Army </Th> <Th> RAAF </Th> </Tr> <Tr> <Th_colspan="5"> Enlisted </Th> </Tr> <Tr> <Td> OR - 3 </Td> <Td> E-3 </Td> <Td> Able seaman </Td> <Td> Private proficient </Td> <Td> Leading aircraftman / woman </Td> </Tr> <Tr> <Td> OR - 2 </Td> <Td> E-2 </Td> <Td> Seaman </Td> <Td> Private </Td> <Td> Aircraftman / woman </Td> </Tr>

What is the lowest rank of junior officers in the royal australian navy