My oldest took her first flight at 6 weeks, my youngest at 11 days. They have continued to fly frequently on flights as short at 2hrs and as long as 15hrs. I'm no expert but these are the things that have helped me survive flights in general, with one or both of my girls, especially when I was flying with both of them alone.
Reserve A Bassinet If You Are Flying Internationally
After you book, immediately call the airline and let them know you are traveling with an infant and would like to request a bulkhead seat so you can have access to their arm saving bassinets. Each airline has specific rules on age, length, and/or weight limits on the child using the bassinet so speak with the customer service rep when booking for specifics for that airline. This is amazing especially for overnight flights when you don't want to risk dropping baby or need to eat or pee! The downfall to the bassinet is if you are traveling with another adult some airlines only allow for one parent to sit in the bulkhead seat as they reserve them for parents with babies. In order to secure the other seat the other adult might have to pay to upgrade to economy plus or hope the seat is empty and move after take off.
Use Your Carrier
Who doesn't want to be hands-free? From carrying your diaper bag or carry on luggage to using the bathroom using a carrier will be a life saver. Technically airlines do not allow the baby to be in the carrier during landing and take off so be prepared to hold baby during those times if the flight attendant says something to you. Baby wearing in general tends to keep babies calm and they sleep well in them so I highly recommend this for international flights as well if you are unable to secure a bassinet.
Book a Window Seat
By booking a window seat you can entertain your child by looking out the window. If they are sleeping or trying to sleep it gives you the power to have the window shade open or closed for added darkness. Lastly the window seat gives you extra privacy when nursing.
Ask for an Extra Seat
Get to the gate early and ask if there is an empty seat so you can have more space with your baby. Most gate agents/flight attendants are more than willing to help you be as comfortable as possible. If there is and you are traveling with your car seat that is approved for aircraft's you can even have baby sit in it for the flight for a safer ride.
Take Off and Landing
Remember babies can't stop their ears from popping due to the pressure of the plane when taking off and landing. If you are breastfeeding, feed baby on take off and landing. If you aren't, be sure to give them a bottle or a pacifier. In my experience, if they are sleeping they will be fine and it's best not to wake them.
Pack some toys that will keep your baby intrigued and occupied. Make sure the toy doesn't make too much noise as to not bother the passengers around you.
Extra Clothing for Everyone
Be sure to bring an extra pair of clothes in case your little one makes a mess. Not just for them but for you too, just imagine if by chance they vomit all over you and you have to sit in your soiled cloths the remainder of the flight.
Pack 1 diaper per hour in flight plus extra for while you wait to board, for when you land and even more to cover any unexpected delays. If you have a layover be sure to account for that as well. Pack the diapers and wipes in a ziploc bag so they are easy to access when it's time to change your baby. Click here for our diaper bag packing list.