We're going to Spain in June and I am planning to get my DS his own seat on the plan as he is very unlikely to be happy sitting on one of us for that length of time.
Has anyone done this and used a Type 1 car seat on a plane?
Is there an issue with size of seat? Is it necessary to take a car seat or would it be acceptable to just sit him in the chair and strap him in 
Last year he just sat on my lap, went to sleep and it was fine but this year he is more active!