Silly goyim

And I say that as someone who is also non-Jewish, although I do have a minor in Judaic Studies, so I knew what the tefillin are. But I guess to the uninitiated they might look suspicious. His grandmother is right, though, we're very skittish in America (not that we haven't had cause), but the boy did explain what he was doing to the flight attendant who questioned him, and he was very cooperative with everyone. She went ahead and reported it to the cockpit, and they decided on the safe side to divert the plane. At least now maybe those non-Jews out there who haven't seen or heard of the ritual will understand a little better, though, so I guess something good came out of it.

A Flight Is Diverted by a Prayer Seen as Ominous (Jewish Teenager's Tefillin Diverts a US Airways Flight)

To some people in New York, that is a relatively common sight: an observant Jew beginning the ritual of morning prayer. But to at least one person on US Airways Express Flight 3079 on Thursday — the flight attendant — it looked ominous, as if the young man were wrapping himself in cables or wires....

[T]he flight crew had never seen tefillin, small leather boxes attached to leather straps that observant Jews wear during morning prayers. The flight crew “didn’t understand what it was,” he said, and the pilot “erred on the side of caution and decided to radio that in and to divert the flight.”

Thanks to YKWIA (my go-to person for all things Jewish) for letting me know about the story.