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Technically our stage 1 seats could be secured with a lap belt by going through the 2 side clips but all the ones I've owned have had a third anchor point at the back of where the head is and we've always been advised to secure using a 3 point, so always have (first was born 1997, last was born 2010- DH did remind me though the seat we were given, but never used, with our first in 1997 was a secure with lap belt only one but we were able to buy a new one before she actually arrived so it never got used)
So technically you could secure it by lap belt only but we're strongly advised only to do that as a complete and utter last resort if no other belts are available in the car, we're fortunate though that all the cars my kids travel in have enough 3 point belts.
Just checked the UK Britax site and it says... " A rearward facing infant carrier must only be used with a 3-point belt. The same applies to boosters (also in combination with a backrest). For the installation with a 2-point lap belt the ECLIPSE and the PRINCE are suitable. They allow your child (or one of your children) weighing between 9 and 18 kg to be transported safely and comfortably in the centre position of the rear seat, even if it is only equipped with a 2-point lap belt."
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Isn't it no wonder no one knows what set of rules to follow when it seems like every country, or even different parts of the same country, seem to have so many varying rules than seem to change every few years![]()
Thanks Notursula, that does make alot of sense, I know here carseats in all cars made after a certain date are a universal length (or greater) and in theory fit around all modern carseats (In theory- I've known a few that don't even though on paper they should)
My kids were absolutely fascinated driving through Fl. that we saw no roundabouts- our hometown is actually quite famous in England for having a stupidly high number of roundabouts so it seemed really odd for them LOL
Car makers like Ford here tell us to try and avoid the centre seat for carseats, especially infant ones but I can definitely see why it'd be the safer seat in a road system where the bigger risk was side impact crashes from cross sections.

yep Zeebs- the one with the calendar!
Learning to drive here was not fun! I absolutely hate driving around islands and have no way of leaving our home by car without hitting at least 2 major ones before getting onto a main road... nightmare!My kids were absolutely fascinated driving through Fl. that we saw no roundabouts- our hometown is actually quite famous in England for having a stupidly high number of roundabouts so it seemed really odd for them LOL

this was US Airways, they don't require birth certificate
http://www.usairways.com/en-EU/travel_information/children/infants_children.html
US Airways defines an infant as a child less than 2 years (24 months) of age. Infants less than 2 years of age must be accompanied on all flights and in the same compartment with an adult at least 18 years of age. We recommend that you travel with a birth certificate for children between the ages of 1 and 2.
I prefer my child not be an air bag or flying projectile in case of turbulance.
Denise in MI

It's the same principal as being on a bus and having no seatbelts.
The worst flight I have ever been on was when we were coming back from WDW with a probably 23 month old lap child behind us. She was miserable. Mom was miserable. We were miserable. She cried and squirmed and kicked the back of my seat the whole time (3+ hours). Her mom sang her this really annoying song over and over and over again. Her sister was saying "Sissy, Sissy, what's wrong Sissy?" for hours. At that moment I decided I would always buy my child a seat!
Another flight I was on (actually my son's first flight at 3 months old- yes, he had a seat) there was a "lap child" a few rows behind us. The FA questioned the girl's age but mom said she was under 2 (this was US Airways, they don't require birth certificate). Mom camped her out on the seat next to her and was super huffy and annoyed when someone had a ticket for that seat. I couldn't really see the child so I didn't think much of it, except for that she was a pretty good talker for under 2, but some kids are. Well, when we got off, I saw why the FA questioned it, she was as tall as my waist. There is NO way she was under 2, probably more like 4. People are nuts. We say "If you can't afford it buy your baby a seat, you can't afford your vacation." The FAA and AAP have been asking the airlines for years to do away with the free lap child policy. I wish they would.

Kids whose parents can't get them under control is bad parenting not seating arrangements. In a car seat or not you take the kid to the back of the plane by the bathroom and you rock her or whatever back there. When a kid gets an ear infection sometimes it can't be helped. They are going to cry and fuss the whole time. This still has nothing to do with the seating arrangements. I've never had problems with kids on the lap and in my case it saves me 1000 dollars. So far all I've heard about is bad parenting and fictional lost reenactments.![]()
Kids whose parents can't get them under control is bad parenting not seating arrangements.
I prefer my child not be an air bag or flying projectile in case of turbulance.
Denise in MI

Hmmmm.... well it says recommend. I know they did not ask this mom for one (at least the FA didn't, I suppose they could have at check in, except most people check in online.) The mom sort of pretended not to speak much English when the FA was questioning her on the child's age, but spoke much better English to the child when they were talking to each other on the flight. I went to the restroom mid flight and I saw the child in the lap and mom did look pretty miserable- so if she was truly over 2 (which I highly suspect she was since she was as tall as my waist- she stood next to me when we all waited for our strollers at gate check) Mom may rethink it for next time. She really seemed annoyed that someone was in that middle seat and had the girl siting there with her blankie and all her toys when they boarded.
I've never had trouble handling my dinner tray in turbulence so I doubt a kid that is heavier would be problem.
Interesting grasp on physics you have there...
So get 2 plastic bags and fill them with rice or something like that. Make it so the difference in mass of the bags is the same as ooo, lets say a baby and a tray of food. Okay now grab a baking pan or a tray or some sort of stable platform. Now go outside put both bags on the tray, hold it with both hands (one on each edge) and start running. Your natural running motion is going to cause the tray to go up and down. Let me know what one moves more? That is what I mean. Not Pick up the bags and throw em at your face and figure out what one hurts more. That is NOT what I'm talking about.