“Aircraft have two or more radios for a reason.”
Every light aircraft I flew or flew in had one radio.
Post 9/11, having just one radio is a huge liability. Even the little training helicopters I get lessons in have two radios now.
While this incident was pre-9/11, after Iran Air Flight 655 got shot down by the Vincennes in 1988, *YOU MAKE SURE YOU LISTEN TO 121.5!*