 At one point , rumors flew concerning possible German gun @-@ running activities ; and Yorktown patrolled off the entrance to Subic Bay and from thence to Lingayen to keep a lookout for the filibusters . She continued coastal patrol work over the next three years , cooperating with the Army , transporting and convoying troops , and patrolling wide areas of often badly charted waters . Upon occasion , Yorktown served as " mother ship " to smaller gunboats , providing officers and men to staff the smaller patrol craft . Ensigns William Harrison Standley and Harry E. Yarnell ( both future admirals ) and future naval historian and archivist Dudley Wright Knox were among the junior officers who served in Yorktown during this time . 
