Page:CAB Accident Report, Pennsylvania Central Airlines Flight 19.pdf/64

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from 400 to 600 feet of altitude is normally lost in restoring normal flight. The intentional stall, being initiated with the airplane's nose pointed up at a steep angle, does not strictly simulate the conditions of an inadvertent stall due to gusts encountered while in level or nearly level flight. It is impossible to produce that condition for test purposes. Any uncertainty arising on that score is added to uncertainty concerning the effect of intense turbulence during a recovery from a stall, and to uncertainty concerning the effect of bad visibility in making it difficult to estimate the amount of altitude that might have been lost during recovery if the airplane had stalled under the conditions existing at the time and place of the Lovettsville crash. It would seem most unlikely, in view of testimony that the training of Captain Scroggins and all other Pennsylvania Central Airline pilots flying the DC-3 had included many stalls and recoveries therefrom, including some under simulated instrument conditions with no dependence on outside visibility, that the airplane would have lost anything even approaching 5000 feet of altitude in the course of recovery from a stall uncomplicated by other factors than those of mere atmospheric turbulence and inability to see the ground.

It is conceivable that a stall might start a spin, although inadvertent spins with aircraft of this class have probably been even rarer than stalls due to turbulence while flying at normal speed. In view of the limited experience, it is impossible to speak with any certainty of how the aircraft would behave in a spin, although it is again true that recovery from a fully developed spin would normally be expected in much less altitude than is believed to have been available in this case between the height at which the airplane was cruising and the point at which it stuck the ground. It is