I landed amongst new army -- the army! (8)
I believe the answer is:
military
'army' is the definition.
(I know that army can be written as military)
'i landed amongst new army' is the wordplay.
'landed' becomes 'lit' (I've seen this in another clue).
'amongst' indicates putting letters inside (I've seen this in other clues).
'new' indicates anagramming the letters.
'i'+'lit'='ilit'
'army' is an anagram of 'mary'.
'ilit' put within 'mary' is 'MILITARY'.
'the' acts as a link.
(Other definitions for military that I've seen before include "Relating to soldiers or war" , "Related to soldiering" , "Relating to armed forces" , "soldierly" , "in the field" .)