What I thought was an airplane flying at a distance, wasn't an airplane at all.

This happened many years ago. A neighbor pounded on my door and asked me to come out and see a "UFO". We were on the north shore of High Lake, Noble Co. , IN looking south. I saw what appeared to be an airplane traveling from east to west at quite a distance. I told my neighbor it was just an airplane. Suddenly it appeared to stop and I told him it was turning and either coming toward us or going away from us. Suddenly it shot upwards, looking like a "shooting star" only in the wrong direction, until it disappeared. Assuming it was originally traveling around 350 MPH like an airplane would, it had to take off in the upward direction at least 1500-2500 MPH. That was the night I became a believer in UFOs. The only discription I can give is that it looked like an airplane at a great distance, but what it did could not be explained by any air craft I know of.
Witness indicates that the date of the incident is approximate.  PD