@DancingDavidE wrote: Here's the regulation: https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC%20120-87B.pdf Number 19 seems to indicate that you could put one in a middle seat if only one child was using the car seat. It's still not explicit that you could or couldn't have two side-by-side as long as the adult was in the aisle. My take on it would be allowed as long as the adult can reach the window seat to undo the belts in an emergency. All of that said - maybe this would be an option going forward instead of using two car seats: https://www.southwestaircommunity.com/t5/Family-Travel/CARES-harnesses/m-p/75683
... View more