As aircraft had just about the same capacity as the 737-300 but proved to be more efficient ... This aircraft was ...

While the aircraft is undeniably new, its registration number—N315UA—has raised eyebrows, as it was once worn by a United Airlines Boeing 737-300, according to the data on planespotters.net.

Federal officials are clearing the way for grounded Boeing planes to resume flying. This comes less than a month after the Alaska airlines mid-air incident, where a door panel blew off a 737 Max 9.