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accomplished, and the collision evidence of both aircraft was studied and documented. This study revealed that initial contact of the two aircraft was between TW 42's left outer wing and the right hand outboard vertical fin and stabilizer tip assembly of EA 853. The relative motion was such that the wing passed, leading edge first, through the horizontal stabilizer from the outboard leading edge to the inboard trailing edge. The average angle of this relative motion was measured at 40 degrees downward relative to EA 853's longitudinal axis, and at a 78-degree angle to the right of EA 853's longitudinal axis.
The captain's and first officer's static system selector valves were found in their respective No. 1 static source positions on EA 853. The Eastern Air Lines L-1049C flight manual provides a No. 1 (normal) static source correction factor of minus 43 feet to be applied to the altimeter indicated reading at an indicated altitude of 10,000 feet, 210 KIAS, gear and flaps up. This correction factor would give a corrected indicated altitude of 9,957 feet when the aircraft's altimeter indicates 10,000 feet.
A review of the maintenance records of the Eastern Air Lines Constellation fleet reflects static system leakage rates of up to 1,000 feet per minute. The rate of the leakage was found using test equipment and was not noted on cockpit instruments. These rates of leakage are not directly related to altimeter accuracy in respect to finite numbers. Eastern Air Lines flight tests reflected a maximum 44 feet altimeter error under the most adverse static system leakage rate noted in the tests.
Taking into account all of the possible tolerances and errors, including the EAL flight test data, the maximum error would have ranged from minus 123 feet to plus 81 feet.
1.13 Fire
Nearly all parts of EA 853 were exposed to some degree of ground fire. The right wing was not extensively fire damaged and the right outboard wing fuel tank still contained fuel.
1.14 Survival Aspects
During the time prior to collision, the seat belt sign aboard EA 853 had been on. At collision, passengers reported a jolt and change of attitude followed by an altitude loss and varying degrees of recovery. The captain advised passengers that there had been a collision, that he was unable to control the aircraft and that they should prepare for a crash landing. Passengers were advised by a stewardess to remain seated, fasten their seat belts, and read the emergency instruction cards in the seat back pockets. The captain was again heard over the cabin address system and stated the aircraft was definitely out of control and that a crash landing would be made. He advised everyone to remove sharp objects from their pockets and to fasten their seat belts tightly. Just prior to impact, the captain announced: "Brace yourselves!"
At impact, there was a continuous upslope yaw to the left. The fuselage aft of the trailing edge of the wing broke open on the right side, "hinging" on the left side. All passengers with the exception of one who believed he had been
