Part 78, page 26
DB Cooper-33821Serials MP 164-73, SE 164-81
FBI 164-81, Vault Part 78 p. 26 (DB Cooper-33821), Memo — cooper.theunsolved.net/parts/Cooper-Part-78/pages/26
Transcript
The scan is the source; the transcript is machine-generated from it.
TO: SEATTLE (164-81) FROM: MINNEAPOLIS (164-73) UNSUB: aka NWAL' Flt #[redacted] 11/24/71 CAA - HIJACKING 00156
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1. Line G-I-K-M represents the airplane's flight path as it approached the Portland (PDX) VOR.
2. The cabin pressure "bump" occurred at 0410 GMT, the time being recorded by the NWA Flight Operations Office (NWAFO) in Minneapolis. It is a virtual certainty that the pressure "bump" marks the time that the high-jacker (HJ) left the airplane. The airplane was at Point A at that time, thus the HJ's body would land at Point A if his 'chutes did not open (unlikely).
3. If it is assumed that the HJ was a highly expert parachutist, and would thus free-fall as far as practicable to insure the best accuracy of his touchdown point, he would land slightly to the NE of Point A due to his drifting with the wind from the point of 'chute opening.
4. If the HJ opened his 'chute as soon as he left the airplane, he would drift along the line A-B and would touch down at B. All lines parallel to A-B are lines along which the HJ would drift if he opened his 'chute relatively early.
5. The parallelogram indicated by C-D-F-E represents the boundaries of the probable touchdown area adjusted for possible time errors and for the above described wind drift. It is probably the most fruitful search area.
6. The earliest the HJ could have jumped is 0406, and this point is represented by Point G.
7. The crew believes the pressure "bump" occurred at 0410, but in any even are certain it occurred before o415. If the HJ jumped at 0406 (unlikely) he would land on or near line G-H. If he jumped at 0415 he would land on or near line MN.
8. Based on the above explanation of Figure 1, and on all the assumptions based in its preparation, the following are pertinent:
a. The most likely landing point for the HJ is at, or slightly NE of Point A.
b. His landing point is more likely to be in area C-D-F-E than any other.
c. It is possible his landing point could be anywhere within the area shown (G-H-N-M), but the probability goes down as the ends of this area are approached.
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Figure 1, and this explanation, were prepared by [redacted] of NQA. For further information, call him at [redacted] (office) or [redacted].
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Received. [illegible], DCA FBI Seattle 12/4/71
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DB Cooper-33821
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