Ah, sorry. His premise is that the sled test was flawed, thus the pressure bump may not have meant what the FBI thought it did. Also, he questions whether or not the crew could have felt any pressure changes through a closed cabin door.

The door to the cockpit is not sealed. I think it was the McCoy hijacking they were looking under the door for the hijacker.

The bulkhead door is sealed, the stairwell is not. they knew when the bulkhead door was opened and the stairs lowered. Rataczak explains this in the HBO documentary.

The plane was sealed until the bulkhead door and stairs were opened. you would surely hear and feel anything out of order. the gauges are sensitive and reacted to the changes.

Well then I guess the question would be - If you pull off the hijacking in the metaverse, do you get to keep the money? Does Dr. Zuck have to give it to you?

Well that raises a couple interesting questions...  The crew claimed they felt the pressure bump in their ears. So what was that? That bump was supposedly replicated by the sled test. But I believe I read that the cockpit door was open for that. So a question would be whether the bulkhead doors, especially the cockpit door, was pressure sealed. I could see where it might be, so that if the rest of the cabin lost pressure at altitude, then the cockpit might remain pressurized so that the pilots would stay conscious to fly to a lower altitude. If that's the case, then how would they feel anything pressure related in their ears? Robert99?

Both the cockpit and cabin would be unpressurized when the aft bulkhead door was open even slightly.  So both the cabin and cockpit would be essentially at the ambient 10,000 foot pressure which was about 70 percent of sea-level standard pressure.  I'm not sure exactly what effect the aft stairs slamming back into the fuselage would have on the cockpit pressure or any way to determine it.  But I will take the crew's word for what they experienced and saw on their instrumentation.

377 has previously posted of his experience in jumping from the aft stairs of a DC-9 which had the stairs removed so that the jumper basically took a dive through the opening from slightly up in the fuselage.  If I remember correctly, 377 said that he could tell when a jumper went out by a change in the cabin noise level without looking at the jumper.  Perhaps he can elaborate on this noise and any pressure changes he felt.

Another factor in the flight crew's experience was that they had been told that Cooper would probably blow up the plane when he jumped.  So if they heard a large bang from the rear of the aircraft they might do some jumping themselves to add to what they were already experiencing.

In my personal opinion, the oscillations were made by Cooper as he was throwing things out and needing to get the stairs down slightly to do that.  And that the pressure changes or bumps were caused by the stairs slamming back up into the fuselage.

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Well that raises a couple interesting questions...  The crew claimed they felt the pressure bump in their ears. So what was that? That bump was supposedly replicated by the sled test. But I believe I read that the cockpit door was open for that. So a question would be whether the bulkhead doors, especially the cockpit door, was pressure sealed. I could see where it might be, so that if the rest of the cabin lost pressure at altitude, then the cockpit might remain pressurized so that the pilots would stay conscious to fly to a lower altitude. If that's the case, then how would they feel anything pressure related in their ears? Robert99?

Both the cockpit and cabin would be unpressurized when the aft bulkhead door was open even slightly.  So both the cabin and cockpit would be essentially at the ambient 10,000 foot pressure which was about 70 percent of sea-level standard pressure.  I'm not sure exactly what effect the aft stairs slamming back into the fuselage would have on the cockpit pressure or any way to determine it.  But I will take the crew's word for what they experienced and saw on their instrumentation.

377 has previously posted of his experience in jumping from the aft stairs of a DC-9 which had the stairs removed so that the jumper basically took a dive through the opening from slightly up in the fuselage.  If I remember correctly, 377 said that he could tell when a jumper went out by a change in the cabin noise level without looking at the jumper.  Perhaps he can elaborate on this noise and any pressure changes he felt.

Another factor in the flight crew's experience was that they had been told that Cooper would probably blow up the plane when he jumped.  So if they heard a large bang from the rear of the aircraft they might do some jumping themselves to add to what they were already experiencing.

In my personal opinion, the oscillations were made by Cooper as he was throwing things out and needing to get the stairs down slightly to do that.  And that the pressure changes or bumps were caused by the stairs slamming back up into the fuselage.

Thank you for the answer. I'm familiar with the sound, that happens in pretty much any jump plane, you can hear the wind flow changes as people exit. But since it doesn't come anywhere near 'sealing' the whole of the door, it doesn't really create any noticeable pressure effect. That the cockpit door is not pressure sealed from the rest of the cabin is kind of the operative issue here. The crew reported the 'pressure bump', and that was replicated in the sled tests, so that would pretty much have to be a result of the door rebounding from Coop's jump. The original question was about Edwards' claim that the stairs were locked down, which would prevent them from rebounding. So if that was the case, what else could possibly cause the pressure bump? Not clear if he has an answer for that.

As for your 3rd paragraph - What's that old crude joke ending in " 'So did you jump?'  'A little, at first.' "  hehe

interesting that air density has a wind load effect that's measurable, even for the variation in tall buildings.

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Accurate determination of wind load is of great importance for the wind-resistant design of building structures. Despite the fact that air density varies systematically with altitude, and somewhat less so with barometric pressure, air temperature, and latitude, there is a lack of studies on the dependence of wind load on air density especially for highrise buildings. This article presents a special study on this topic. The dependence of air density on latitude, season and altitude is investigated first, based on meteorological records at several national stations in China. The height-dependence of air density in the inner region of a tropical cyclone (TC) is highlighted, since there is a fast development of highrise buildings in TC-prone areas and TC wind load dominates the design wind loads for such slender wind-sensitive structures. A data-driven model for the height-dependence of TC air density is established. It is shown that the measured TC air density is reduced by 8%–10% compared with the values recommended in the wind load codes. The dependence of wind load and wind-induced structural response on air density for a supertall building is then analyzed through a combined usage of the proposed TC air density model and wind tunnel testing. Results suggest that the wind load and wind-induced response of the building obtained by considering the height-dependence of air density can be decreased by as much as ~12% compared with those without considering such effects. Thus, more economic wind-resistant designs for highrise buildings may be achieved by taking into account the height-dependence of air density.

Mean roof height is always used to determine wind loads..different parts of a building react different. corners are "end zone" conditions where winds can double causing anchor spacing to increase. a window in the center of a building could have attachment spacing of 6" on center. the same window on a corner will call for 3" inch on center.

Most things are over engineered. impact windows will fail with the glass blowing out vs the whole window.

agree with all that
Yet:
People want to argue that a single sled test, is sufficient for determining what happened when Cooper jumped or didn't jump.

The sled test represented something close to what happened with Cooper. But to say there's enough data to say it was the exact same thing? Nope.

Variation exists. Saying you know the extent of variation is silly without tests that cover the variations.

I suggested variation when the plane is turning. Sure you can laugh at that, but it seems like a thing to me.

It's always open to debate. they did have the guy who reported what happened during the hijacking on the plane recreating what happened. he appears to have agreed they recreated the same issues heard and felt that evening. putting them together seems to be the hurdle nobody has gotten over to date.

Might not be a factor of data vs eyewitness account?

Good point.
Yet, people will claim they "know" based on I don't know what.