I use the car seat on the plane for a multitude of reasons. Foremost is clear air turbulance. Just as with a car, a lap belt is not sufficient protection for a small body. The car seat has a 4 point harness and will keep him in his seat if something unexpected happens. As far as getting him out in an emergency. Hey, after putting him in and taking him out of that thing about a million times, I know those straps and buckles like the back of my hand and can have him out of it in 3 seconds flat if need be.

As far as convenience, it is his comfort zone. As with a car ride, he mentally knows that if he is placed in that seat, he's in for a journey that could last 3 minutes or 3 hours. We've tried just putting him in an airplane seat with just the lap belt and within an hour or so, he is squirming to get down on the floor or stand up. Lastly, just like the car, he is comforatble in a seat that fits him and is more likely to nap on a long journey.

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