OK, so how does this differ from what you expect?
DECLARE @AmendBarsetFlight TABLE (RowID int IDENTITY(1,1), XMLBeforeAction xml, XMLAfterAction xml)
INSERT INTO @AmendBarsetFlight(XMLBeforeAction, XMLAfterAction)
VALUES('
<xml_node>
<test>XMLBeforeAction</test>
</xml_node>',
'
<xml_node>
<test>XMLAfterAction</test>
</xml_node>'
)
SELECT XMLBeforeAction,
XMLAfterAction
FROM @AmendBarsetFlight