<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (May 2010) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (May 2010) (Learn how and when to remove this template message) </Td> </Tr> <P> Senior Airman (SrA) is the fourth enlisted rank in the United States Air Force, just above Airman First Class and below Staff Sergeant . It has a pay grade of E-4 . Between its approval on 30 December 1975 (with implementation 1 June 1976) and 19 March 1991, Senior Airmen wore sleeve chevrons with blue center stars instead of silver to distinguish them from the non-commissioned officer rank of "Sergeant", also a pay grade of E-4 . The latter was abolished in 1991 and the blue center star was changed to white to conform to all enlisted rank chevrons . </P>

When do you put on sra in the air force