Page:CAB Accident Report, Eastern Air Lines Flight 14.pdf/21

 and the fourth pilot said that he encountered "some turbulence". Similarly, these statements are by no means conclusive of the precise degree of turbulence that was encountered by Trip 14, since these pilots did not enter the storm at the same time and the same point at which Captain O'Brien made his entry.

The Specialist in Meteorology of the Board made a thorough analysis of weather conditions in the area in question based upon sequence reports, radio sonde data, and reports from pilots flying in the area on the morning of April 3. He concluded that the condition existing near Vero Beach at the time of the accident could not be considered as more than a mild frontal system in which severe turbulence could be expected. The analysis did not indicate the presence of turbulence more severe than might be expected in a local thunderstorm or moderate frontal condition, there being no evidence of a tornado or severely cyclonic condition existing in the area.

The passengers, in describing their sensations while the airplane was in the storm area, stated that articles in the cabin were thrown from the racks and at times were suspended from the top of the cabin. They alternately had the sensation of being pressed in their seats and being restrained from leaving their seats by the safety belts, thus indicating that the airplane did ascend and descend rapidly. These statements lead to the conclusion that the airplane did encounter severe turbulence, but they are by no means conclusive in determining whether the turbulence was of that degree of intensity that would have made control of the airplane impossible.

The testimony of Captain O'Brien and First Officer Crabtree displays substantial differences of opinion as to the degree of turbulence encountered, the instrument readings and the maneuvers of the airplane while they were in the turbulent air. Captain O'Brien's description of the flight with the attendant turbulence leads to the conclusion that the turbulence was of such intensity that it became impossible to have complete control of the maneuvers of the airplane. First Officer Crabtree's testimony leads to the conclusion that the airplane did encounter severe turbulence, but not of a degree of intensity that should have resulted in loss of control of the airplane. In weighing this testimony, we must take into consideration the relatively limited experience Captain O'Brien had accumulated as captain in operating DC-3 equipment on instruments in turbulent conditions and the fact that First Officer Crabtree's DC-3 experience was limited to operation as copilot for about seven months. Captain O'Brien stated that during the first updraft the air-speed indicator showed an ascent of 1000 feet a minute, while Crabtree testified that during this first up-draft the air-speed indicator went past a reading of 250 m.p.h. and the rate of climb indicator showed an ascent of 2000 feet per minute. Captain O'Brien stated that the indicated air speed was between 190 and 200 m.p.h. at the time they broke out of the overcast, while Crabtree testified that as they broke out of the overcast the indicated air speed was between 60 and 70 m.p.h.

Captain O'Brien and First Officer Crabtree also expressed a difference of opinion as to the reading of the bank and turn indicator. Captain O'Brien stated that during the turning maneuvers the ball in the bank and turn indicator was in the right corner and the hand was as nearly centered as possible, only oscillating approximately its own width. First Office Crabtree testified that at least during what he believed was a spin the ball in this indicator was in the right corner and the hand was in the left corner. As to the maneuvers of the airplane while it was in the turbulent air, the captain stated that following the first updraft they encountered a series of up and downdrafts, each approximating 5—30827