Uhh, that's not how it works. 15 year olds aren't permitted to accompany 11 year olds to avoid the UAM procedures. 16 year olds are permitted to accompany younger children outside the UAM procedures. 15 year olds may fly unaccompanied by themselves, but they have to be 16 to supervise younger children.

So do you think your 13 year old can pass for 16? If so, then have at it. One tip: the typical airline ticket agent, gate agent and flight attendant aren't all that stupid. They'll be able to tell the difference between a 13 year old and a 16 year old.

Children under 18 don't have to show photo ID to clear security, but airlines are free to require proof of age for any children (and many do require proof of age, like a photocopy of a birth certificate).

My advice? Buy them tickets on a different airline that permits younger children to fly alone than AA does under its newer, more restrictive rules. When new management took over at AA, the ages were increased so that fewer children would be permitted to fly alone without the expensive UAM fees/rules.

Welcome to Flyertalk.

If I were you, I would not expect your experience to be duplicated next time your child flies AA or US. The ages and rules are the same at AA and US. "One time at band camp" exceptions happen all the time, but others probably shouldn't plan on them.