A low-lying placenta at 12 weeks often moves away from the cervix as pregnancy advances. With no bleeding and normal vitals, 14 weeks is a reassuring stage. Short flights are usually fine this early if you're otherwise well, though a placenta covering the os is worth a quick check before you fly.
Next Steps
Ask your obstetrician for clearance and a fresh scan if it has been a while, then carry your pregnancy file during travel. Keep moving your legs and stay well hydrated on the flight and the drive.
Health Tips
Postpone the trip and get care right away if you notice bleeding, spotting or cramping at any point.