Page:CAB Accident Report, 1965 Carmel mid-air collision.pdf/15

- 14 - conclusion is based on the surviving crewmembers' testimony, passenger statements and testimony as to cloud conditions being experienced just prior to the accident, and the flight engineer's log of EA 853 made some 20 minutes prior to the accident.

Both aircraft were being operated on IFR flight plans and were under the control of the New York ARTCC. Altitude separation between these aircraft was being provided in accordance With existing procedures. Neither aircraft was given (nor is there a requirement to give) an advisory as to the presence of the other aircraft even though the controllers testified they observed the converging tracks. Both aircraft had reported to ATC at their assigned altitudes and all evidence indicates they were flying at these altitudes shortly before the collision occurred.

There was a solid overcast in the vicinity of the Carmel VORTAC. New York Weather radar showed tops 12,000 to 16,000 feet to the north and 8,000 to 12,000 feet to the south. Pilot reports, passenger reports, and crew testimony establish that in the near Vicinity of Carmel, the tops were generally at 10,000 feet with small buildups or puffs in evidence.

The testimony of the first officer of the EA 853 indicates that he first observed a jet at about his 2 o'clock position and that the jet appeared to be at their altitude. At the time of sighting, EA 853 had Just emerged from a cloud and as he (first officer) observed the other aircraft, he shouted a warning to the captain who was flying the aircraft. Both he and the captain pulled straight back on the yoke in an effort to evade the other aircraft. He further testified that after EA 853 was in its climb, he observed the Jet bank to the right. Actual tests of a Lockheed L-1049C in the weight and configuration similar to EA 853 indicate the aircraft could have climbed 1,000 feet in altitude in approximately 9 to 14 seconds

The first officer of EA 853 testified that the crew departed from their assigned altitude when they sighted the TWA aircraft. This departure occurred because the first officer, and apparently the captain, believed the aircraft he saw was on a collision course, at or very near the altitude of EA 853. The Board believes this impression was caused by an optical illusion. A review of the weather information obtained during this investigation shows that the cloud tops were relatively smooth with some "cauliflower" type buildups protruding several hundred feet above the general cloud tops. The evidence also indicates the tops of the clouds were generally higher to the north and northwest of Carmel. The first officer, knowing his aircraft was passing through or very near the tops of the clouds, observed another aircraft on a converging track. With higher clouds behind TW 42, the first officer would receive an impression of an aircraft on or very near the apparent horizon. In the small amount of time that he had to judge the separation of the two aircraft he had no visual aid to assist him in determining the true horizon and the buildup of clouds toward the north would present a false horizon on which to base his analysis of separation.

The most logical explanation of the reaction pullup is again based on the small amount of time the crew had to evaluate the relative position and course of the other aircraft. They would not have been able to determine whether the other aircraft was in level flight in or just above the tops of the clouds or in the process of letting down and just entering the clouds. Had EA 853 pushed over, the aircraft would have gone into the solid overcast and the crew would have had no way to observe and evade the converging traffic if it were also entering the clouds.