seen a strange object standing still in the ski shoot off at about a 15 degree angle and out of sight in about 2 seconds

myself my brother and 2 freinds walked down some railroad traks to go do some shooting with bb guns after reaching our destination we split into two groups. afte what seem to be just a few minutes we regrouped and started walking home. all of us exhausted and non of us having fired a shot. Stange for us or any teenage kids.As we were walking home i glanced into the ski and say what looked like a crumpled pice of plactic floating in the ski, like a wind blown tarp.As i watched it i realized it was not moving and had kind of a haze around it. This was on a clear sunny day and i don't think there was a cloud in the ski.It was a gray silver in color and had no lights. As i watched it took off from a stand still to out of sight in just a second or two. it shot up at slight angle   went straight for an airliner flying over head jumped over it and out of sight.i did point this object out to the people with me. they looked up at it and then put there heads down and kept walking. i did not speak of this for years but have always remember this.My brother says he dosn't remember it and the friends have sence moved away.This happend a long time ago and my memory might be flawed, this is the first time i have relayed to anyong out side my familey  amke of it what you will