 Four of the German Imperial Navy boats — UB @-@ 3 , UB @-@ 7 , UB @-@ 8 , and UB @-@ 14 — were selected for service with the Constantinople Flotilla . All were sent to Pola for assembly and trials there as part of the Pola Flotilla before sailing on to join the Constantinople Flotilla . UB @-@ 3 disappeared en route to Constantinople in May 1915 , but the other three arrived there by mid @-@ June . 
 Four of the German Imperial Navy boats — UB @-@ 3 , UB @-@ 7 , UB @-@ 8 , and UB @-@ 14 — <a href='uninflect' title='1'><mark>were</mark></a> selected for service with the Constantinople Flotilla . All <a href='uninflect' title='2'><mark>were</mark></a> sent to Pola for assembly and trials there as part of the Pola Flotilla before sailing on to join the Constantinople Flotilla . UB @-@ 3 disappeared en route to Constantinople in May 1915 , but the other three arrived there by mid @-@ June . 
4 of da German Imperial Navy boats — UB @-@ 3 , UB @-@ 7 , UB @-@ 8 , and UB @-@ 14 — was selected for service witt the Constantinople Flotilla . All was sent to Pola for assembly and trials thea as part of the Pola Flotilla b4 sailing on to join the Constantinople Flotilla . UB @-@ 3 disappeared en route to Constantinople in May 1915 , but tdaother three arrived tdereby mid @-@ June .