Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human-Machine Interface; Training / Qualification
Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
Flight Crew Overcame Equipment Problem
Environment - Non Weather Related; Human Factors
During the second half of our flight from ZZZ to ZZZ1 while in the cruise portion of the flight; the FO pointed out the transponder was still in ALT On and not TA/RA. We switched it to TA/RA and continued the flight. My mistake for not visually confirming during the 'Before Takeoff' Flow and Checklist and my recommendation is to remind crews to really take their time and visually identify items are completed because a lot of us are going weeks or might go a month or longer without flying since COVID lessened our customers desire to travel. Best case I would recommend rotating people through scheduled trips to try to get people to fly at least every other week to maintain everyone's proficiency; but I understand that may be a tough wish.
Air carrier Captain reported not recognizing until cruise that the transponder was set incorrectly. Captain recommended that crews visually confirm checklist items since many pilots are flying infrequently due to COVID-19 reductions in travel demands.