A car seat is not required on any airplane, although you may opt to bring one (or a child restraint system for an older child) on the plane if you purchase a seat for a child under two, or are traveling with a child over the age of 2 that may benefit from being in a seat. However, a car seat is a must for baby to keep him/ her safe if you plan on traveling by car with baby once you arrive at your destination.
While in Chicago, we mostly use public transportation (buses, train), and do not own our own car, so we rarely use a car seat unless we are using a Zip Car or a taxi. We own two different car seats, so I certainly have not tried traveling with many, but have looked into many different options and many are not ideal as far as bulkiness/ weight for travel.
The Lily Gold Sit’N’Stroll is the only product that I have found that is a combo car seat/ stroller and that is truly convenient for international travel. It has gone through a lot of trips with us (15 + international journeys and 40 + legs), and is still going. It’s great because the wheels and handle (the stroller portion) just easily fold up into the car seat (like an airplane). This makes it really easy to put baby in the seat in the airport, pop it out, push it to the airport curb, and then pop everything back in and stick baby in the back seat of a taxi or car rental (it comes both with a securing mechanism and with the ability to use a conventional lap belt to buckle across the seat). It is also fairly lightweight compared to other seats.
It also saves on extra luggage if traveling with a stroller and a separate car seat, and is much more compact. If you buy an airplane ticket for baby, it is also FAA-rated, so you can use it on the plane. It’s also been great for layovers if you gate check it and retrieve the seat when you get off the plane during your layover (although we’ve found it’s much easier to just check it in with our luggage and carry around baby using the Moby wrap, and many international carriers take gate checked luggage and check it all the way through to the final destination).
The only negatives are that it’s not a stroller that I would use on a regular basis (it’s more just for in airports and to-and-from travel), and it can be clunky to deal with if you are traveling in a taxi, for example, in a developing country, and have no where to push/ put it once you arrive at your destination. So, if you need a stroller for walks (especially in places without lovely sidewalks as the U.S. has), then you might need a regular stroller and car seat, instead. We have personally found strollers to be pretty useless most places we go where sidewalks don’t exist and we rely on a baby wrap to carry baby around, so it has not been an issue for us.
Although I personally would never, ever travel with the Diono Radian Convertible Car Seat (read my full review), some parents swear by this car seat. I suspect they are not taking this car seat on international trips with them. I did purchase this seat in hopes that it might be another good option for us, but we only use it at home in a car and will not ever travel with this. The seat does fold flat and comes with a carrying strap for transport. It can be used forward or rear-facing, and has a 5-point safety harness, and due to its compactness parents can fit three in a row in a backseat of a car.
There are also many angry consumers that say that the SUPER LATCH mechanism that keeps the seat secured malfunctioned and the company is unresponsive to hundreds of consumer complaints. It looks like the company has fixed the error on all products made after 2011, and has sent out replacement latches for older models, though, so perhaps checking on manufacture date for those made after Feb. 2011 would be appropriate if you’re interested. Newer models (under the company name Diono) since March 2011 include: Radian RXT, Radian R120 Daytona, Radian R1oo. Older models (under the company name Sunshine Kids) that are no longer manufactured (but are still on the market for sale) include: Radian XTSL, Radian 80SL, and Radian 65SL.
Other travel car seat options that I have not personally used, but that I have read about other travelers having success with:
Hybrid Convertible Booster: This is a lightweight seat at only 11.5 pounds that folds up for easy carrying. This is a forward-facing only seat that has a 5-point safety harness and works with kids up to 65 pounds, after which it converts to a booster seat for kids up to 100 pounds. Although this product has received great reviews, I did not purchase one myself, as a vehicle must have a latch on the back seat in order for the seat to function (and not collapse since it has a soft back). I wouldn’t recommend use for travel to another country, especially a developing country, where having a latch in a rental car or taxi is an unknown.
Safe Rider Travel Vest: This is a vest that a child old older than the age of three wears that attaches to a regular seat belt. Once my oldest is old enough to not ride in a car seat and we are traveling, I may consider purchasing this as a travel-friendly lightweight option to keep my children safe when in cars overseas.
CARES Child Aviation Restraint System: This is not a car seat, and is only meant for airplane travel for children old enough to sit in their own seat. I personally think this is unnecessary. Parents who have used this and think it is helpful, please reply here as I would love to hear your thoughts.
If you do plan on gate checking a car seat, I recommend getting a gate check bag that it will fit into to protect it if it is checked at the gate (plane door), or a heavier duty bag if you plan on checking it with luggage. There’s lots of room in the Jeep bag, so we can usually throw in other things along with it. I also recommend, for any car seat or things with straps, getting strap covers to protect baby’s neck from the uncomfortable strap with a softer cushion.