Adobe Flash Substitute
Puffin Browser (free with limitations, 99¢ to subscribe for 6 months)

Photon Flash Player ($9.99)

You could also use many remote desktop applications to stream from a desktop PC or Mac. Probably doesn't help much on a flight, though.

Source: http://www.computerworld.com/article/2599798/apple-ios/how-to-run-flash-on-your-ipad-if-you-must.html