Craft desending ,from high rate of speed to a very slow speed, traveling across Gardner Lake - Landeed on east side of lake

My cousin and my self were sitting on the bck porch of the cabin , facing the east. Object flew down from behind us in a desent entering our field of view. We wached it fly very low and slowly all the way across Gardner Lake. When it reached the other side it stopped and hovered for a few minutes next it desended to the groung and landed. We could still see the light from it shinning through the Pine trees at night. After sitting on the groung for a few minutes it next began to rise back up to its original altitude and hovered for a few more minutes. Next it began to move towards the SE. Its rate of acceleration seemed to increase very rapidly, so much so after a few ( may be 10 sec ) it was traveling like a bulet. It disapeared going off in the SE.