MD-11
Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Diverted; General Flight Cancelled / Delayed; General Maintenance Action
Procedure; Company Policy; Aircraft
Both HF radios and SATCOM tested OK during preflight; although I noticed an extended amount of time; 5-10 seconds to tune HF #2. HF #1 and HF #2 were respectively set/tuned to ZZZ radio primary/secondary on the ground. Upon reaching cruise; although we could hear ZZZ radio; we could no longer tune a new HF frequency or transmit on HF1 or 2; nor receive SELCAL. SATCOM voice was intermittent with several failed attempts to contact Dispatch.CPDLC (Controller Pilot Data Link Communications) was working with Center; so we texted and advised them of the scenario and that we were attempting to work with Dispatch and Maintenance on a plan of action. When we finally got a hold of Dispatch/Maintenance; Maintenance suggested we might try CB resets of one/both radios; but the AOM does permit it for the HF system because it is not a procedure in the QRH or AOM. Dispatcher suggested we follow AOM/QRH procedures. FOM requires at least one HF functional for the CEPAC RNP10 airspace. Although Center was willing to let us proceed; via CPDLC text; with the spotty SATCOM and an FOM that mandated at least one fully functional HF with SATCOM; there seemed to be no other option but to [return to the departure airport]. We decided to [amend release and return to the departure airport] for Maintenance.
MD-11 Captain reported returning to departure airport after both HF radios failed.