I don't think the placard proves anything but where the plane was, or could of been. we don't know if it was at the very bottom, middle, or top, or if Cooper threw it and it went right out with a lucky frisbee toss? Cooper was on the plane at 8:05...the stairs didn't move until 8:10, but could of been on the stairs for a period of time..
the whole area was searched above the Lewis, and below...then you have issues of area's not properly searched due to heavy brush (thickets) even discussion on what side of the airways they were on.
The failure to get an accurate position makes things hard to pinpoint as we can see reading the files and how they changed the search area's after recalculating the path and timing. if you are implying Cooper survived, then it doesn't matter where he jumped. you could say he jumped at 9:47....one document states to look as far as the Columbia, so I guess I could take this and run? it's possible, but not enough proof...
two separate calculations were done, one by NWA, and the other was the Air Force. both were almost exact in plotting the possible jump time.
then we have to big oscillation vs pressure bump debate...
The placard has no memory or a clock with respect to the bump. (any more than the wieners at Aldis Foods did)
The CVR, FDR, and money do. The radar tapes might. Soderlind used what was available. Because:
quote: "Rataczak added that at no time did he have any direct contact with or talk to or observe the hijacker, so could furnish nothing to the physical description.
Anderson added that no member of the crew went back to check on the presence of the hijacker immediately following the ‘oscillations’ the crew encountered. When the subject let hostess Mucklow go to the cockpit she locked the door behind her.
Anderson added, it had not occurred to them at the time to pinpoint their exact location at the time of the oscillation … "
because, apparently while they did think oscillations meant Cooper was playing with the stairs, or on the stairs, none of the crew immediately associated the pressure spike with a jump. (weight off the stairs). None of the crew were experienced sky divers. But, the lights went on in other people's minds immediately upon hearing of this, especially at Minneapolis.
I seriously doubt Solderlind would have wasted his time thinking about the placard even if he had known about it.