Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Overcame Equipment Problem; General Maintenance Action
Aircraft; Human Factors; Procedure
Taxiing out we were to hold short of [taxiway] and contact ground. The FO (First Officer) transmitted but ATC did not hear him; we tried again and then I tried on my side to contact ground; they did not hear us. Ground control then called 'who's at [taxiway]?' and we could not reply. I asked the FO to switch to comm 2 and try again; that was successful. We were given the runway assignment and taxi clearance. I started following the given route to the runway. While taxiing I tried to see if any button or knob was out of place so we could transmit; but to no success. As we got closer to the runway I determined that RTU 1 (Radio Tuning Unit) was not transmitting; but was receiving. I discussed the possibility of contacting Maintenance. I was trying to figure out what to do; and did not have a solid answer whether to go or not. After discussion with the FO about FAR's dealing with IFR flight on one radio; I came to the decision to go on the flight because we had Comm 3 available as a backup and I still could receive on Comm 1. That was a mistake. Enroute I ACARS Maintenance control and they advised to call when on the ground. I also notified Dispatch of the problem. As we flew I checked the QRH vol 1 to find any answers and read a Min. Equipment List that stated only 1 VHF is needed for flight; so I felt justified in departing; figuring we would be able to defer the radio. I talked with Maintenance control and we came to the conclusion that the Comm 1 was broken. I asked Maintenance to defer the radio and was told that Comm 1 is NOT deferrable because it's on the hot bus bar for emergency power loss. That's when I realized I made a mistake in departing.
Captain asked me how I felt about departing and I told him I was unsure. Captain felt pressured to stay on schedule and did not want to return to the gate. I need to be more assertive when unsure of a decision being made.
CRJ-200 flight crew reported departing with Comm 1 transmitter inoperative; but discovered after landing that Comm 1 was not deferrable.