Page:CAB Accident Report, Pennsylvania Central Airlines Flight 19.pdf/45

 associated with the nearby storm and the general dullness of the day. In that case the airplane might actually have disappeared into the storm at a height considerably greater than 1,000 feet. If it had entered the storm at 4,500 feet above the ground, its path from that point to the point of impact would have been inclined to approximately 26 degrees to the horizontal, or at an angle about equal to that at which the airplane most probably struck the ground. Although the assumption of a steady dive at an angle of 30 degrees or thereabouts is in superficial conflict with Mr. McGaha's impression of the airplane as going down very steeply, the conflict is reduced by taking account of the angle to the horizontal of Mr. McGaha's line of vision on looking at the airplane. With the airplane in a 26-degree dive at a height of 5,000 feet (taking that as the altitude at which the dive might have become well established at a fixed angle), and at a distance of two miles short of the point of final impact, Mr. McGaha would have seen it at an apparent angle of 51 degrees to his line of sight. The apparent length of the airplane, as seen at that angle, would be foreshortened by less than a quarter of the true length, and even an observer quite familiar with the form of aircraft and their appearance during maneuvers might have difficulty in distinguishing the machine seen at such an angle from one diving very near to the vertical.

If the airplane had gone into a vertical dive at a height of 5,500 feet above the ground, while traveling at normal cruising speed, its speed would have increased to approximately 380 m.p.h. at the time of striking the ground. A similar study for a steady 30-degree dive from the same altitude indicates a speed at contact with the ground in that case of about 330 m.p.h. These figures are very approximate, but suggest the general order