Portal:Civil Aeronautics Board

“ In this experiment, as the miss vector (distance between aircraft either vertically or horizontally) decreased, the frequency increased in which a decision was made that a collision course existed.
The evaluation of a target may depend on the observed angular velocity (sight line rate) [11] and the observed rate of change in angular subtense (range-rate) [12] rate of the target. If the sight-line rate of a target is well above the motion threshold the pilot can be fairly certain the target is on a non-collision course. ”

“ The average rate of turn of four degrees per second requires an average 35-degree bank angle, which is within five degrees of the 30-degree bank angle normally considered maximum for passenger confort in DC-7 aircraft. The radius of turn resulting from a four-degree rate of turn is approximately 4,100 feet. Using these data a flightpath was projected on a heading reciprocal to 170 degrees, beginning at the previously determined point of passage, for 23 seconds at a groundspeed of 206 knots. Application of wind drift then produced a track of 165 degrees. ”

“ At this point Eastern 663 and Pan American 212's targets merged but I could still distinguish them as two targets "
As to the kind of separation being provided the RR-7 controller said that with the departure handoff controller's statement of "not quite a thousand feet" departure control was going for vertical separation. However, at a later point in his testimony he said "It was radar separation prior to Eastern starting to turn. Once (the aircraft) . . . proceeded southbound, once he was on a southerly heading-the radar separation was lost on my scope." ”

“ Autokinetic illusion results from the continual observance of an isolated light in the dark where no other visual references are available. The observed light, although in a fixed position, gives the impression that it is moving. ”

“ The first officer, on the other hand, could probably have kept PAA 212 in sight throughout the entire time from initial detection until passage of the airplanes.
Spatial Disorientation Study
The term "spatial disorientation" in its broad sense means the inability determine one's position relative to one's environment. This inability results in mental bewilderment and confusion. The aircraft pilot is susceptible to many types of illusions which result in spatial disorientation, such as vertigo, ocular gyral illusion, autokinetic illusion, and inadequate stimuli. ”

“ With the aforementioned data the paths of the two airplanes were reconstructed to determine the angle of elevation of the target airplane and the captain's visual altitude limitations from his alert position at the various ranges of the target aircraft. Table I indicates the bearing, range, and angle of elevation of PAA 212 from Flight 663 in five-second increments. The right 35-degree bank is started at time X and rollout on a 170-degree heading at time X+:18 seconds. Art average altitude differential of 700 feet was utilized throughout the development of these elevation angles. ”

“ Even when they are not severe they will reduce the visual stimulus levels to a point where orientation to the earth or other objects becomes faulty. This is particularly hazardous when flying over snow, water, or other areas barren of clearly defined landmarks. It results primarily im marked decrease in depth and distance perception."
In the Sperry Gyroscope Company Study [10] one experiment was conducted to determine the effect of pilot warning indicators on the ability of the pilot to discriminate between aircraft on collision and noncollision courses. ”

“ Pan American Flight 212 (PAA 212) was on a Instrument Flight Rules (IFR) flight plan from San Juan, Puerto Rico, to JFK Airport At 1818:38 the New York Air Route Traffic Control Center initiated a handoff to the Kennedy Approach Control Arrival Radar Handoff (ARHO) controller and advised that PAA 212 was then three miles north of the Dutch Intersection. ARHO accepted radar identity of the target and instructed the New York Center to have the traffic turn (from 330 degrees) to a 350-degree heading. ”

“ The initial coordination between the AR-3 and DR-l controllers took place at approximately 1823, or shortly after the DR-1 controller turned EAL 663 to a 100-degree heading. Both controllers testified that at approximately 1823:24 further coordination and an exchange of altitude information was effected. However, a review of the transcription of recorded communication at the DR-l position revealed that this controller was engaged in almost continuous communication with EAL 663 and other aircraft during this time period. ”

“ A frequently experienced example of this miscue is an indication of motion when, in fact, you are standing still. In a stationary train the movement of an adjacent train often gives the impression that your train is in motion. ”

“ The wreckage of EAL 663 was located by Sonar Soundings on the ocean floor at a water depth of 70-80 feet. The location of the crash site was 13 nautical miler southeast of the JFK Airport. (See Attachment #2.) Wreckage distribution was confined generally to an area 125 yards wide and 400 yards long.
Over 60 percent of the aircraft was recovered, including portions of all major components. The investigation revealed no evidence which would indicate failure or malfunction of the aircraft's powerplants, systems, or structural components prior to impact. ”

“ Neither sufficient time nor adequate information was available to the EAL captain for him to assess properly the relative attitudes of the two aircraft.
12. The EAL captain had the illusion that a potential collision course existed. As a result of this illusion a descent was initiated.
13. During this descent, PAA 212 executed an evasive maneuver that would appear to negate the action taken by the EAL captain. The only course of action available to EAL 663 at this time was a rapid roll to the right, and/or a pullup. ”

“ Thereafter, the aircraft would have to turn to a heading of approximately 236 degrees and travel the seven miles to the crash site at an average groundspeed of 365 knots. That an aircraft would proceed on a track 50 degrees displaced from the assigned heading without causing some concern and query on the part of the controller is difficult to accept. ”

“ Cross the 157-degree radial of JFK VORTAC at 4,000 feet or higher and; remain on/or north of the JFK 141-degree radial until 3.5 miles east of the Deer Park 228-degree radial. ↑ The minimum distance between aircraft required for radar, lateral or horizontal separation is three miles. The required distance between aircraft for vertical or nonradar separation is 1,000 feet. ↑ EAL policy requires that captains of four engine equipment occupy the left seat during all flight operations. ↑ A study of requirements for a Pilot Warning Instrument for Visual Airborne Collision Avoidance. ”

“ The turn was described by the PAA 212 crew as faster than normal but not abrupt. Based on these observations and the testimony of RR-7 controller we calculated that the turn took 20 seconds, since on the next sweep the target was southbound, and was observed for two additional sweeps. ”

“ In this circumstance the DC-7 was placed in an unusual attitude, resulting in spatial disorientation of the crew.
↑ All times herein are eastern standard based on the 24-hour clock. ↑ Dutch 7 Departure - After takeoff from runway 31L/R, climb on a 290-degree heading to 1,000 feet m.s.l., turn left heading 160 degrees for two minutes. Kennedy VORTAC 224-degree radial at 2,500 feet m.s.l., then via vector to V139; V139 to Dutch Intersection. Cross Riverhead VORTAC 237-degree radial or below 4,000 feet. ”