Traveling by plane to Islip, NY from Austin, TX. Changed planes in Nashville, TN. Plane flew over Atlantic Ocean I believe to be off the coast of Virginia. Sky was blue w/white clouds, noticed in the middle of all the blue & white a black oval cloud, which seemed out of place since everything else was blue sky and white clouds. Kept observing cloud for a couple of minutes when suddenly it seemed to turn and change into the shape of a helicopter, still in a cloud like state, all fuzzy with no definite edges. I could see the top props, the body of a copter & landing skis the suddenly it turned again & was back in the shape of an oval black cloud & at that time it appeared to fire a silver type projectile from it. I observed this for about 5 to 7 minutes before the plane I could no longer see it. I don't know if it was a UFO or some sort of stealth helicopter or what. I do not know if this is anything ya'll would be interested in, but it feels good to get this off my chest.