L1011-500 MAINTAINING FL310 WAS UPDATING INS FOR OVERWATER ROUTING AND MISSED A FREQ CHANGE NEAR WAL VOR. ABLE TO ESTABLISH COM WITH CTR BY REF TO THE AERO CHART.

Narrative

IN CRUISE AT FL310 WBOUND ON UB-1 APCHING WALLASEY VOR; WE STARTED TO PICK UP STATIC AND THEN AN ATIS BROADCAST ON #1 VHF COM. I SWITCHED TO LONDON CTL ON 131.05. THEY INDICATED THEY HAD BEEN TRYING TO CONTACT US FOR SOME TIME. WE HAD BEEN CLRED DIRECT GOLES INTXN; THEN FLT PLAN RTE BY LONDON CTL AND SHORTLY AFTER THAT GIVEN A FREQ CHANGE. I ACKNOWLEDGED THE SWITCH. THE NEW FREQ WAS INITIALLY CONGESTED; SO I WENT BACK TO THE TASK OF VERIFYING WAYPOINTS IN THE INS. IT WAS EITHER A WRONG FREQ OR I DIALED IT IN INCORRECTLY AND APPARENTLY NEVER CHKED IN. IT SOUNDED LIKE A NORMAL ATC UNTIL THE STATIC AND THEN ATIS. SUPPLEMENTAL INFO FROM ACN 367930: I ALSO HAD TO ACCOMPLISH THE INS NAV ACCURACY CHK PASSING OVER WAL VOR BECAUSE I WAS EXPECTING A DIRECT CLRNC FROM WAL TO THE OCEANIC ENTRY POINT (WHICH WAS WHAT WE RECEIVED) AND AN ACCURACY CHK OF THE INS IS REQUIRED BEFORE PROCEEDING IN MNPS AIRSPACE. I WAS ENGROSSED IN WORKING WITH INS AND DID NOT HEAR THE FO MISS A FREQ CHANGE OR FAIL TO CHK IN ON THE NEW FREQ.