Travel carseat help! and booster questions

[aahjed]

We're taking our 3 kids on a cross-country airplane trip. DS will have just turned 6, DD1 is almost 3, and DD2 is 9 months.

At home, DD2 rides in a Safe Seat. DD1 has 2 roundabouts. DS has a Radian XT and Britax Frontier 85.

For our trip, DD2 will ride in her SafeSeat. I'm thinking that I'll bring the Radian for DD1 because it will fit better on airplanes than the RA. For DS, I'm thinking of ordering a backless booster and having it ready at our destination. During our trip, we will be driving from Seattle to Portland and back (about 2.5 hours each way).

Is DS old enough for a backless booster? I know all his friends have backless boosters because he's been asking about them lately. But I'm really really worried about not having him in a 5-point harness. At the same time, with all the stuff we have to carry for 3 kids, lugging a 3rd carseat is really unappealing.

What do I need to know about using a backless booster? What do I look for in choosing a backless booster?

[Joolsplus2]

Yes, he's old enough for a backless. Do you know what car you'll be in? If he's a car sleeper, put the Radian on his shoulderbelt side so he can lean on it to sleep :).
THE lightest current booster is the Harmony Lite Rider from Walmart http://www.walmart.com/ip/Harmony-Juvenile-LiteRider-Youth-Backless-Booster-Car-Seat-Beige/15047826?sourceid=1500000000000003260330&ci_src=14110944&ci_sku=15047826
Unless you aren't traveling till the BubbleBum is available... http://thecarseatlady.blogspot.com/2010/12/bubble-bum-most-innovative-backless.html

But currently also the lightest safety product to travel with is the RideSafer Travel Vest... you can stick it in a backpack, and it offers the safety of a 5 pt harness. It's not as cheap as a booster, but I really like traveling with it, and you'll be able to use it for years with all three kids.... http://www.amazon.com/RideSafer-Car-Seat-Travel-Vest/dp/B000KCV61U (and yes, my kids loved it, because it's 'Not a carseat!!!!')

[mom2binsd]

Does DD1 ride RF, if so I'd bring the RA for ease of installation in a rental car, you never know with a Radian. I don't think the RA is an issue on the plane, it'll fit just fine.

[aahjed]

Thanks for the input.

DS is sometimes a carsleeper, but in any case, I'll definitely put him in the middle, because he'll have no sideimpact protection. The safeseat has no side impact protection, but at least she will be riding backwards.

We'll have to rent a minivan when we get there, although I'll also give the kids the option of riding with my brother. I think he'll be driving his Audi All-Road station wagon.

And DD1 rides FF.

That vest thing looks so cool! Is it comfortable for the kids? Do they put the vest on, then you belt them in?

[aahjed]

And one more question: in my board search, I see reference to "submarining" in relation to using a booster seat. what is that and how do i avoid it? also, are there any guides/tipsheets as to proper use of a booster seat?

[Joolsplus2]

Thanks for the input.

DS is sometimes a carsleeper, but in any case, I'll definitely put him in the middle, because he'll have no sideimpact protection. The safeseat has no side impact protection, but at least she will be riding backwards.

That vest thing looks so cool! Is it comfortable for the kids? Do they put the vest on, then you belt them in?

The Safeseat has loads of Side Impact Protection, just no little label proclaiming it (primarily provided by being RF, of course you're right on that, but it's got deep sides and EPS foam, way better than some competing brands that claim SIP on flimsy plastic booster headrests :tongue5: :))
Anyway, the Vest is pretty easy to usually leave hooked up half on the belt and on the top tether so kids can just squiggle back into it when they get in the car, rather than fully taking it out and putting it on every time. It's a bit of a learning curve, but nothing you can't overcome.
Don't worry about submarining, that's what boosters *prevent*, even in little kids (and a 6 yo is more than big/mature enough to fit right and sit properly). I don't have a specific 'how to' page, but here're my girls in a generic backless with good fit (well, Leah was the minimum, but boy, those minimums should be higher. ugh) http://carseatblog.com/2171/combi-dakota-review/ You can see the lapbelt is low on the lap, and the shoulderbelt is centered on the shoulder. The LiteRider is super easy to buckle and I haven't yet met a kid that didn't fit it, big or small, so that's why I love it so much (I should take pictures, because of course I own one, lol).