Which of the following is NOT required equipment for day VFR flight?

The correct answer highlights that radio communication equipment is not a requirement for day VFR (Visual Flight Rules) flight operations. Under the regulations governing day VFR flying, a pilot must ensure that the aircraft is equipped with certain mandatory instruments and equipment to safely operate during the day. This includes an airspeed indicator, an altimeter, and a fuel gauge, all of which are essential for monitoring the aircraft's performance and ensuring the safe management of flight operations.

While having radio communication equipment is certainly advantageous for maintaining situational awareness and for communicating with air traffic control or other aircraft, it is not mandated for day VFR operations. Therefore, pilots may fly without a radio, as long as they comply with all other regulatory requirements and safety protocols during flight. This flexibility reflects the nature of VFR flights, where visual cues and navigation are primary, and reliance on radio communication may vary based on the location and airspace being navigated.