▁and ▁ ▁at ▁night ) ▁anti - sub marine ▁and / or ▁anti - sh ipping ▁operations ▁as ▁a ▁safety ▁measure ▁should ▁one ▁of ▁the ▁radial s ▁develop ▁problems . ▁ ▁Normal ▁crew ▁access ▁was ▁via ▁a ▁lad der ▁on ▁the ▁a ft ▁bulk head ▁of ▁the ▁nose w heel ▁well ▁to ▁a ▁h atch ▁on ▁the ▁left ▁side ▁of ▁the ▁wheel ▁well , ▁then ▁forward ▁to ▁the ▁observer ▁nose , ▁or ▁up ▁through ▁another ▁h atch ▁to ▁the ▁main ▁deck . ▁There ▁was ▁also ▁a ▁h atch ▁in ▁the ▁floor ▁of ▁the ▁a ft ▁fus el age , ▁near ▁the ▁son ob u oy ▁ch utes . ▁ ▁Oper ational ▁history ▁ ▁Early ▁Cold ▁War ▁ ▁Prior ▁to ▁the ▁introduction ▁of ▁the ▁P - 3 ▁Or ion ▁in ▁the ▁mid - 1 9 6 0 s , ▁the ▁Ne pt une ▁was ▁the ▁primary ▁U . S . ▁land - based ▁anti - sub marine ▁pat rol ▁aircraft , ▁intended ▁to ▁be ▁operated ▁as ▁the ▁h unter ▁of ▁a ▁'" H unter - K iller " ▁group , ▁with ▁destroy ers ▁employed ▁as ▁kill ers . ▁Several ▁features ▁a ided ▁the ▁P - 2 ▁in ▁its ▁h unter ▁role : ▁Son ob uo ys ▁could ▁be ▁launched ▁from ▁a ▁station ▁in ▁the ▁a ft ▁portion ▁of ▁the ▁fus el age ▁and ▁monitor ed ▁by ▁radio ▁Some ▁models ▁were ▁equ ipped ▁with ▁" point able " ▁tw in ▁. 5 0 ▁cal iber ▁machine ▁guns ▁in ▁the ▁nose , ▁but ▁most ▁had ▁a