Date: 202105
Local time of day: 1201-1800
Location: ZZZ.ARTCC, US
Flight conditions: IMC
Light: Daylight
Aircraft: EMB ERJ 170/175 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class E ZZZ
ATC / advisory: Center ZZZ
Aircraft component: VHF
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Troubleshooting; Communication Breakdown
Second reporter function: First Officer; Pilot Flying
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Pre-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Overcame Equipment Problem; Flight Crew Landed in Emergency Condition; General Maintenance Action; General Flight Cancelled / Delayed
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: On Departure out of ZZZ the crew experienced significant audio distortions on COMM 1. Switched to COMM 2. In the vicinity of ZZZ1 contact was lost with ATC for a period of approximately 10 minutes. ACARS was also lost at this time. Upon reestablishing contact ATC was able to hear the crew loud and clear but on board the ability to receive ATC transmissions was significantly degraded and there was significant static and noise on both frequencies. As the flight progressed the quality of the reception continued to degrade and COMM 1 became completely unusable. The QRH was run and the MEL; FOM and AOM (Aircraft Operation Manual) were utilized. The decision was made to Identify as an emergency and continue to the planned destination. Due to the inability to contact the company; ATC was requested to tell the company of the communication issue. As the flight progressed the quality of the reception continued to degrade on COMM 2 until it was barely usable. Upon entering the approach segment of the flight NAV 1 and 2 provided unreliable lateral and vertical information. The flight concluded safely at the destination. Flight crew that handed off the aircraft noted issues with the ACARS no other pertinent information was provided by the crew as they departed. ACARS was usable for the preflight and initial departure portion of the flight.The cause of the radio communications failure is not known by this crew member at this point in time.Air traffic control was very professional and they were immensely helpful and indispensable throughout the event.


Second narrative: While departing ZZZ; on climb out and then more noticeable as we neared ZZZ1; static / screeching distortions were noted on COMM 1. At least three times; we asked ATC how they heard us; and the reply was 5x5. We could hear ATC at a 2 or 3. We advised ATC of this. Conditions deteriorated throughout the flight; causing us to utilize COMM 2 as primary.After a short period; COMM 2 began a degradation similar to COMM 1. All flight instrumentation; engine gauges; etc. showed normal parameters. QRH / FOM checked; Captain and I monitored and with COMM 2 not improving; and notification updated information to ATC; Identified as an emergency. Plan and back up plans were made by crew; flight attendants briefed; company notified. Flight continued with no further issues. It should be noted that during a period of time; no COMMS were heard; and we queried ATC to make sure we had not lost all communication. Additionally on approach (visual conditions) both lateral and vertical guidance was observed unreliable. Furthermore upon accepting the aircraft from the previous crew; the Captain noted issues with the 'ACARS' noting we may have to reset the ACARS.The cause of the action is outside of the scope of this crew member. ATC was outstanding. Helpful professional and went above and beyond.


Synopsis: Flight crew reported both VHF communication systems malfunctioned; and they elected to continue to destination airport.