I believe the oscillations were occurring the moment the stairs dropped early in the flight. they might not have been major but you have an airtight plane and any disruption will be noticed. they should increase as the stairs lower and pressure will be pushed inside when they retract. you should get negative and positive loads.

The plane was in a climb while Cooper was trying to open the stairs. this put more wind load on the bottom of the stairs. the plane was not in level flight. they leveled and slowed the plane down where Cooper could get the stairs to react.

The conversation between the crew and Cooper is really needed other than him saying, twice he couldn't get the stairs down. the crew was aware when the bulkhead door was opened. odds are they will know when the stairs opened partially.

The test was done to determine when Cooper left the plane. not when the stairs were unlocked, or when he was on the stairs. it was to try and recreate when he left the stairs. the sounds should act similar to speaking into a tube. it will travel up and through the cabin into the cockpit. I would guess while the pilot was on the stairs in testing the guys near the stairs inside must of heard the noise going on outside much more than the pilots. it will dampen the sound to an extent. as mentioned before, they knew when the bulkhead door was opened. Ratazcak was very dramatic about this.

Once the stairs went back up it pushed air into the plane. it doesn't need a slamming affect. It sounds like Cooper just went for it by going down the stairs and jumping. it doesn't really show any gaps between going down and jumping. waves of pressure will come into the plane similar to slightly opening one window in a car pushing air in and out of the car. that would be positive and negative loads.

I see nothing in Anderson's interview that proves FJ's contentions. We have no record from any source including the Boeing test group that verifies any timeline was followed, especially the timeline of events as they occurred during the hijacking with respect to the order of specific events. All Anderson says is 'oscillations followed by a bump occurred in that order resembling what he experienced during the hijacking. What Andy does not tell us is 'when' and 'under what conditions' with respect to the sled drop.

The hijacking order is: At 19:45 'we have aft stair light'. At 20:12 we have "Flt 305 advises they are getting some oscillations in the cabin, Cooper must be doing something with the stairs."  No 'bump' is ever reported to Flt Ops. This 27 minute gap was not duplicated in the Boeing test, if time matters.

Anderson DOES NOT SAY: "The sled test showed that the oscillations/fluctuations INCREASED AFTER the weight left the stairs NOT BEFORE." which is Fly Jack's scenario!

Stair lite goes on at 19:45. Oscillations not reported until 20:12. Why the 27 minute passage of time and no report of oscillations ? Did the Boeing test duplicate this 27 minute passage of time with the stairs unlocked (but not down-extended ?) ... when exactly and in what context did oscillations and bump occur during the test as it occurred during the actual hijacking? We dont know. We arent told if anyone knows.  This uncertainty opens the door to FJ's scenario: 'The sled test showed that the oscillations/fluctuations INCREASED AFTER the weight left the stairs NOT BEFORE.' 

So, the order and timing of events during the hijacking was not strictly followed or duplicated by the Boeing test! Moreover we are not given any timeline and condition of the stairs during the whole Boeing test!

All we have are three still photos (frames from a video) taken by a chase plane monitoring the test. If we assume these three photos are consecutive frames then from the time of the first frame to the last showing the sled dropped and falling, that time period is fractions of a second! The sled is dropped and the stairs instantly snapped back up .......... is that when Anderson felt his oscillations and bump during the Boeing test? After the sled had been dropped? When weight was now off the stairs which is FJ's theory? Neither Anderson or any other source document makes this apparent. 

Nobody has ever told us when and under what conditions during the Boeing test 'oscillations/bump' occurred!            

Flyjack could be right! According to FJ oscillations and bump were experienced after frame #2 in the photo below!  Is that what Anderson said but didn;t clarify and make specific?  Anderson simply never states when and under what conditions he felt the same oscillations and a bump! Especially with respect to the three photos posted of the Boeing drop...

As mentioned earlier, oscillation would be similar to cracking a window allowing pressure or wind to enter. the bump would be forcing air into the cabin and cockpit. there is a difference and Anderson explains this calling the retracting of the stairs the largest bump by far. testing the stairs would disrupt less, especially if he was slow going down the stairs. two copycat hijackers made claims of going down the stairs slowly. this would be shown slowly on the gauge and differ from pushing pressure into the plane. noticeable sounds would follow.

According to what Anderson is claiming is similar to what I've explained. they all agreed when Cooper was on the stairs but it was physically noticed when he left.

The gauges indicated disruption of airflow. that would be oscillations. the gauges would also register when the steps went back upward adding physical evidence of retraction (leaving the plane) felt through the ears (pop)

One document in quotations tell a story of both occurring closely. if that is true, then we are not missing any dialog of an exit after the time reported in the transcripts.

Oscillations not reported until 20:12. Bump ends the period of oscillations ?  Time of jump ~ 20:12. Place of plane ?

Time of jump ~ 20:12. Place of plane ?

Well, if you go by what the simulator told me. it's about where they first believe Cooper bailed if you wish to accept the map they produced. all I noticed was the extra time between the Lewis and the Columbia and the heavy turn around 8:16, if not mistaken.

One piece of simple housekeeping! The idiot bot at DZ saz: " My conclusion is simple,, the FBI got the LZ right and Cooper jumped about 8:11. That is well short of the Columbia R. So, Georger needs to prove the FBI's LZ is wrong. He can't. "

HUH!?  Georger has never claimed any lz! The FLY JACK gamer bot at DZ needs to revise its brainless disinformation hate program! Duhhhhhhhhhhhh.      

FLYBOT is now joined by some new Trojan horse at DZ. para-DZ. Apparently Blevins has spawn a clone with superior genes at DZ.   

more from the Anderson interviews .... with para-DZ's, FLY BOT, and Greg the Tecky Guy's permission of course.

"Q10:  Did the flight crew report the pressure pulse immediately after it happened?  If so, over what comm circuit?
A:  That’s a good question because we may have reported the oscillations/pressure changes once, but we were busy and didn’t report it multiple times. We weren’t sure what was going on. When the final bump happened, which we detected with our ears, we were surprised, and we didn’t report it right away.  Rataczak finally reported the bump via radio.

Q11:  Why do you think a frequency was set up for use after the "company" frequency? [I've been unable to get a manual for the NWA 727s of the period, but have info from 3 other airlines.  From this it seems that the procedure that was provided by Boeing to the flight crew for allowing the hijacker out via the aft airstair would have included disabling the hydraulic power to the airstair (probably by pulling the circuit breaker in the cockpit) so that the hijacker wouldn't be able to power the stair to the full-down position (and lock it there).
 A:  I don’t recall the specifics of this. Our cockpit was in communication with NWA and ATC.   Not FBI.

Q12:  Did the procedure include disabling the airstair hydraulic power?
A:    We didn't want to disable the airstairs by defusing electrical power to hydraulic actuators.  We wanted the bastard to get off our ship ASAP.

Q13:  Did Paul Soderlind sit in the copilot seat during the test flight?
A:   Yes, I believe that's correct.

Q14:  Who was the NWA instrumentation man who stood behind the rest of the group in the pic?
A:   Do not recall.

Q15:  Who was the FBI agent standing beside you in the test group photo?   (holding the manila envelope and apparently a jacket in addition to the raincoat he was wearing)
 A: Do not recall. 

Q16:  Who was the heavier agent kneeling down in front of you two, in dark clothes?
 A:  To long ago, can't recall.

Q17:  Who was on the test flight other than the 12 people in the group pic?
A:   Don't specifically recall.  Maybe some other Air Force.  Yes, a couple I think.

Q18:  Is there anything else you consider significant to the question of where the hijacker jumped?
A:  It was very dark, with virtually no ground reference except when we got in the Portland area.  We bounced around the clouds, with occasional breaks. The 727’s  slipstream initially overcame the aft stairs hydraulic system.  The stairs weren’t opening like Cooper needed. Cooper called me on the interphone while Tina was riding up front with us. Cooper had let Tina come to the front.  He yelled,  "slow it down!."  I stated back to Cooper, "OK."  And we did;  we slowed the plane. The oscillations continued, as I remember, but were smoother and we hadn’t heard anything from Cooper.  Bill called back to him and he finally answered.  He said everything was “OK”. More time passed. And then suddenly came that “bump”. After the final "bump" which we felt with our ears, we all discussed it for awhile, waiting for another bump.  It never occurred, so we assumed that was his exit.  But we discussed this among ourselves before notifying NWA.  The truth is, we just didn't know for sure.  I just don't recall how much time lapsed between feeling the final "bump" and reporting it to NWA via radio.  That’s where the uncertainty has come from. 
But later we all thought that final bump was his exit.  "


Good night Stella. 

Quote

Cooper had let Tina come to the front.  He yelled,  "slow it down!."  I stated back to Cooper, "OK."  And we did;  we slowed the plane. The oscillations continued.

This confirms what I've been saying about oscillation occurring once the stairs were lowered early in the flight. the cabin rate climb indicator will pick up any difference in pressure to the cabin. dropping the stairs would cause disruption of airflow. anytime the stairs moved should of registered on the gauges which according to the crew they did. anything noticed after the stairs were released would give a constant reading with possible disruptions in flight prior to getting on the stairs and would change the reading once this occurred. then Cooper jumps and air in pushed into the plane causing discomfort to the ears and probably a spike in the gauge.

Carr's point was that there was a difference between 'oscillations' once the stairs were lowered, vs the 'pressure spike' after which oscillations stopped. Cooper has jumped, his weight no longer on the stairs. But during the remainder of the trip to Reno no oscillations are reported even though the stairs are dragging as they land at Reno. The bump is an artifact of Cooper leaving the stairs. I agree with FJ on that. (We all agree!) Where on the flight path was that .

FJ's scenario from his own words:

(A) The Boeing test fluctuations/oscillations increased AFTER the test sled/weight left the stairs. (B) This indicates that Cooper left right before the crew reported increased oscillations at 8:11/10.

By “increased oscillations” FJ means the large pressure spike, socalled “bump’.

FJ seems to be saying Cooper jumped PRIOR TO the bump?

“The sled test showed that the oscillations/fluctuations INCREASED AFTER the weight left the stairs NOT BEFORE.”

Proof:  “As the load left the stairway it retracted to within eight Inches of closing, then dropped back down. The result was a marked fluctuation In the cabin air pressure which caused the crews ears to pop and registered a rapid change In the rate of on instruments In the cockpit.”  FBI p# 23113

The only test report is FBI doc p# 23113.  TAG team issued no public test report.

It’s important to note that the pressure bump occurred AFTER the oscillations, but we don’t know the precise time of the bump. Any attempt to pinpoint a bump/jump time is guesswork.