Hi! I was wondering about this topic. The following assumptions are made: - area is flat and about 70 miles wide from all direction - ideal airplane only changes in height (roll, azimuth, pitch stay constant). So here's the scenario: If a laser beam is mounted on an airplane and is pointed in a 45 degree angle towards the ground (with the right wing of the plane from a cockpit perspective as zero degrees and the angles ascend in a clockwise manner), then would a slight change in the airplane's height significantly alter the location of the beam on the ground? I was just curious about this topic, and on paper, I'm actually using elevation angle instead of height. The elevation angle is defined as the angle formed between: 1) a line from the plane to the ground directly underneath it and 2) a line from the plane to the point on the ground where the beam is pointing. I want to know how to calculate the change of the beam's position when this elevationg angle varies by +/- 1 degree. I know that the elevation angle is dependent on the airplane's height, and that if the airplane was close to the ground then a +/-1 degree change would not really amount to a significant change in position of the beam. But if the plane was, say, 1000 ft in the ground, then this would be a different story. Thanks!