Just fyi they might not allow you through customs at your destination with food depending on what you bring/how much. It might complicate your travel. Last intl flight we took they served so much food and there were always fresh fruits and vegetables included. The servings at each meal were pretty big, so we would swap out stuff with each other to accommodate everyone's preferences. The only food I brought with me from the USA was some candy, but there were restrictions on some foods. Where are you going exactly?

Just go with the camping freeze dried foods. It's light and easy to pack. The airlines alway give out hot water for tea or coffee. They have every meal you could want and they are ready in 5 minutes.

Ice packs should be allowed through, as long as they are frozen when you go through security (so they're solid, not gel consistency like when they're thawed). At least they are on domestic flights, I haven't tried them internationally.

Things that have worked for us on long flights:
- Instant oatmeal packets - ask flight attendant for a cup of hot water
- Instant noodles or soup bowls - same thing
- Beef jerky or shelf-stable pepperoni sticks, if he does OK with those textures/flavors
- Cooked pasta - keeps well at room temp, and my kids would always happily eat a meal of plain pasta
- Canned chicken or tuna fish with crackers, if you don't mind irritating your seat neighbors (could also bring bread and make it into a sandwich if you want to make it feel more meal-like). Shelf-stable mayo packets from McDonalds help here too - bring a ziploc, dump the meat and mayo into the ziploc, smush them around to mix it up, then spread it out onto the bread or crackers.
- Pre-cut fruit and veggie sticks

Go picnic meals from Amazon.com

My son has those allergies. I fed him the airplane food, for the most part. It was fine, but call 48 hours ahead of time and remind them/make sure they have you flagged.

Do be careful about letting him down on the floor to play. Sometimes they can find peanuts down there from previous flights.

Thanks for snack ideas. But I need meals too. This is a 14 hour flight and I don't lunch meat will keep. I don't think they allo ice packs either. Ugh!

I would plan on packing lots of snack foods (crackers, fruit, sliced bread or rolls, etc) and then trying to find food at the airport to bring on the plane for more of a meal. Worst case your kid has a less than ideal meal of just snacks but you probably can find some decent things at the airport. Hummus, deli sandwich, grilled chicken, etc would be able to be picked up at a lot of airports.
Are you flying direct? Which airport?

Travel packs of hummus with crackers in a cooler, raisins, applesauce or fruit pouches, goldfish, animal crackers, dried fruit or leather fruit things.

We always take sandwiches, just not the messy kind.

Freeze dry food camping food. You can alway get a cup or two of hot water, add to bag and you are good to go. You just have to find a meal your kid likes and meets your allergies needs. REI has a lot of them. Rice and chicken wil work. They also have chicken and noodles.

Anything that you'd normally pack in a sack lunch.
If it is a young child, they'll let you through security with wetpacked containers after a wipe-down. You can buy fruit cups and drinks at layovers. Don't stress over it! I always over-prepare for long flights with my kids, and in reality it's not too different from a regular day out with snacks.

Just snacks, or full meals? Which meals? And how old is the child?

For snacks:
Crackers. Pretzels. Fruit (cut and put it in disposable container). A "treat" snack like some cookies or something.

For meals: The noodle idea is a great one, if he's old enough (and likes those). If you'll be on board for breakfast, an instant oatmeal that you add water too? Single serve box of cereal with powdered soy milk?

We were able to take so pouches on the plane with out toddler. They are clean and have some liquid which is nice. On flights to Asia I've seen people bring cup of noodle type things and ask for hot water. Prunes might be good to, I find air travel sort of binding.

Popcorn. Almond butter and jelly sandwiches. Pretzels. Fruits.

Please help me with thinking of snacks and food for a very long international flight for my DS. He is allergic to dairy, eggs and peanuts. We've alerted the airline but I need to be ready just in case. TIA!