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12,000 feet, overcast; Visibility two miles in ground fog; wind south at eight knots.
It was learned that another aircraft, a Martin 404, was standing in runup position near the approach and of runway 23 as Flight 587 was landing. An investigation was made to determine whether propeller wash from this aircraft could have drifted into the approach or touchdown areas and adversely affected Flight 587. It was determined that the 404 was headed north and that its runup had been completed several minutes before Flight 587 made its approach.
Analysis
The investigation disclosed no structural or mechanical failures present in N 44993, prior to the crash, which could have contributed to this accident. All maintenance and inspections had been performed as required and there were no uncorrected or carry-over items. In addition, all witnesses said the aircraft‘s approach up to the time of touchdown appeared normal. Further, both pilots testified that the aircraft had operated normally throughout the flight. For these reasons the Board believes that no discrepancy, either structural or mechanical, existed in N 44993, and that it was being operated normally until just before the first contact with the runway.
Despite the descriptions by the crew that this was a normal skip-type landing, the Board believes that it was hard and that the airplane bounced. First, the tower Operators saw the landing lights appear to tilt upward abruptly. Even though this observation was restricted and cursory, it is evident that the movement of the lights was unusual enough to create the impression of a bounce.
Second, the passengers' statements describe a hard touchdown, a bounce, then a second contact with the runway.
The consensus of the passengers was that the aircraft appeared to roll straight with the runway for a short distance after the second contact with the runway, then swerve to the left. The copilot, in his written statement, corroborates this sequence of events. The only conflicting evidence to this order of happenings was the testimony of the captain and stewardess, who stated that the airplane touched down, skipped, and then swerved to the left immediately and before the second contact with the runway. The preponderance of evidence therefore is that the airplane did not begin to veer off the runway until after the second contact.
Both pilots stated that the weather was substantially better than had been reported. The visibility was good, there was no turbulence, and no noticeable wind effect on the final approach. It is therefore evident that weather was not a contributing factor in this accident.
Another factor considered and dismissed as a contributing cause to this accident was the possibility of propeller wash from the Martin 404 causing the DC—3 to veer off the runway. The Martin pilot had parked his aircraft with the tail (and therefore the propeller wash) pointing away from the landing runway. In addition, the pilot had completed his engine runup and was waiting for the
