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findings indicated none of the persons was struck by lightning.
The findings indicated the pilots had no preexisting physical condition which would impair normal duties and nothing suggested that pilot incapacitation was a factor in the crash.
Board investigators found no evidence in the medical information that was inconsistent with the physical examination of the aircraft. In fact, the information was in accord with evidence found during other phases of the accident investigation.
At 1600 a cold front existed along a line from Philadelphia to Baltimore to near Gordonsville, Virginia. Regional forecasts issued by the Weather Bureau in Washington at 0700 and 1300 and the area forecast[1] issued by the Weather Bureau at Idlewild at 1400 drew attention to the possibility of locally severe thunderstorms and extreme turbulence associated with the front. The front was forecast to be virtually stationary. The 1400 are forecast also stated there was the possibility of a squall line development in advance of the front.
At 1415 the Idlewild Weather Bureau office issued the following flash advisory. "Line of scattered thunderstorm activity near Martinsburg-Harrisburg-Poughkeepsie northeastward is moving eastward about 20 knots accompanied by severe turbulence and conditions locally below 1,000, visibility 2 miles. This line will move to near Providence-New York City-Philadelphia by 1800 increasing in intensity during afternoon. Valid until 1815." The Capital meteorologist located in Washington marked off the areas covered by the advisory on a blackboard chart located on one wall of the dispatch office. The advisory was also available on the teletypes at the dispatch sectors positions in the office.
During the afternoon radar reports were issued about hourly from Andrews AFB weather. These reports described the locations of the thunderstorms and indicated they were increasing in intensity during the afternoon along the New York-Washington route of Flight 75. These reports were also on teletype machines located in Capital dispatch at the sector positions.
About 1548 the cold front passed the Baltimore-Chase area. It was indicated by a pronounced wind shift in about two minutes, a pressure jump of .08 inches of mercury in 20 minutes, and wind gusts to about 45 knots.
According to the Civil Air Regulations and the Capital Airlines Operations Manual, dispatch may cancel or divert a flight on the basis of existent or anticipated adverse weather conditions. The captain of a flight has this authority and under emergency conditions may take such action as he considers necessary in the interest of a safe operation. Dispatch is also required to furnish the en route pilot any additional available information concerning meteorological conditions which may affect the safety of a flight.
- ↑ Volume 3 of the Weather Bureau Manual states: "Flash Advisories deal solely with potentially hazardous weather within a period of 2 to 4 hours in advance while Aviation Area Forecasts include potentially hazardous weather plus other operationally significant weather for a period of 12 hours plus an outlook for the next 12 hours...Flash Advisories will automatically amend the outstanding Aviation Area Forecasts for the period of the Flash Advisory."
