Kind of a bizarre card, in that it's nearly identical to Born Aloft and even came in the same cycle. The only distinctions are that this is an event rather than an attachment, so you don't have to anticipate needing it in the planning phase, and it only applies to eagles rather than all allies. In practice, you can almost always predict which ally is going to want the effect, and eagles are a very small subset of allies, making Meneldor's Flight straight-up inferior to Born Aloft.
In any case, common uses:
Spamming Descendant of Thorondor
Getting cards onto Eagles of the Misty Mountains in a pinch
Immediately usable if you draw it after the planning phase, or play eagles outside of the planning phase
That's about it... It's a really lame card.