I'm a former Flight Attendant and while I've flown Air New Zealand, I haven't since I had children.

Just to clear up some misunderstandings;
1. If you use a car seat, you are NOT obligated to keep your child in it the whole time. In fact, my children hated their car seats so I kept them safe for take-off and landing but they spent most of the flight in my arms or walking the aisles. My kids would have screamed if I had tried to confine them! Sometimes they were unhappy on take-off and landing but hey, their safety was more important and most people are awake during those times anyway (which is shorter than most car rides). It's not like screaming in the middle of the movie, while everyone's asleep...

2. It's a common myth that children are supposed to suck on take-off and landing. It's actually just the start of descent (landing is too late) according to the AAP (and my experience). If they have any ear problems (which can be avoided by visiting the doctor and making sure there's no infection before leaving), they'll cry, which really clears the ears!

But don't worry. Nine years of twice yearly transatlantics with three children, I've never had any problems and mine stayed safely strapped in for take-off and landing.

3. Sounds like it's time for a convertable car seat but please, keep it facing backwards for as long as possible, especially in the car. First time parents often turn their children forward facing too early but any parent may not know that it's five times safer to face the other way. Find out not only if Air New Zealand allows this on the aircraft (as well as if your seat will be allowed on board).

4. While bassinets are convenient if your child does not have a seat, they are not as safe and many 6 month olds will already be too big. It depends on the airline. Also, they can have different rules. One girlfriend told me her baby could not be awake in the bassinet (not convenient!) and of course, the rule about removing them in turbulence.

As a mom who flies alone with her children, I can tell you it's not helpful to not be able to leave the baby in the bassinet asleep. Okay, he's not sleeping on you but you can't leave them unattended in the bassinet for safety reasons. No problem if you have the luxury of having the other parent but that was never my case! In the car seat, you can. I'd slip my car-seat hating children into the car seat (obviously unaware) and I could run to the restroom, or grab a drink. I never left him/them for long, and I always told someone nearby or a F/A where I was but at least I could leave my seat.

In the endless car seat debate is the question of, do you need your seat at your destination? If you take it, the best bet is to have it on board with you. No risk of it being broken or lost in transit. It's grim to arrive at your destination without your bags but then to have your baby unrestrained leaving the airport is downright dangerous. The car seat keeps your child safe in the plane but your chances of a car accident after you land are much greater. Never check a car seat in as luggage and gate-check it if you can't use it on board.

Good luck!
http://flyingwithchildren1.blogspot.com (non commercial flying tips)