What was found
AFTER 2.0 HOURS OF FLIGHT LOUD STATIC AND CRACKLING SOUND HEARD IN ICS SYSTEM. UNABLE TO HEAR TOWER OR INTERNAL ICS COMMUNICATIONS BECAUSE OF STATIC/CRACKLING SOUND. BACKGROUND LIGHTING ON ALL THREE ACU CONTROL PANELS WOULD GO COMPLETELY DARK AND FLASH ON AND OFF. STATIC/CRACKLING SOUND WAS INTERMITTENT. SOME TIMES WOULD BE NORMAL OPERATIONS AND OTHER TIMES UNABLE TO HEAR ANYTHING OVER ICS SYSTEM DUE TO NOISE. OP CHECK: CO PILOTS ICS/RADIO TRANSMIT INTERMITTENT, ICS CRACKLES FROM ALL THREE STATIONS INTERMITTENTLY, ICS PIGTAILS WERE SWAPPED AND PROBLEM REMAINED ON COPILOTS SIDE. REPLACED REU IAW CMM 64460.03. MOC OK IAW UH72 RFM.