We're flying to Australia in FIVE days time and have just discovered our car seat is unsuitable for use in the plane (too wide and doesn't use a lap belt routing). Does anyone have any experience of using a 9-18kg forward-facing car seat on a plane? Which make and model did you use? The Singapore Airlines seats are 17" wide and 7"-8" from the bottom of the seat to the arm rest. The main problem seems to be whether the car seat is narrow enough to clear the arm rest before its arms splay out wider than 17". Our 15-month-old can only fall asleep in his car seat and is a total wriggler. If I can't find a seat to fit, the 24-hour journey's going to be a nightmare. Please help. Thanks.