Depending on how high up the plane is here are some tips.

8 ounce sinker on the end of some light line. You can toss it pretty high, then let the sinker down and pull up some heavy rope to shake the tree.

Spinning rod with sinker. An underhand or overhand cast can get some REALLY high spots.

Find someone who likes to climb trees.

Good luck getting your plane down. At least you know where it is.