Dr. Martenson,

Thank you for your invaluable work on the audio analysis on the attempted assassination of President Trump in Butler.

I’d love to get your take on a couple of videos that seem to capture possible explosions during the collapse of World Trade Center Building 7. I’ve attached two of the cleanest audio versions for you to check out.

The first video is very popular and shows WTC 7 collapsing in what strongly resembles a controlled demolition. You can hear a distinct boom within the first few seconds, right before the penthouse starts to collapse. However, it’s quite subtle and more noticeable when using earbuds or headphones. (https://911warroom.com/wtc7/explosions/WTC7.NIST.Camera.3.mp4).

The second video is of Ashleigh Banfield interviewing someone on the street. During this interview, several people’s heads turn sharply, likely in response to an explosive sound, though it is very faint. (https://911warroom.com/wtc7/explosions/WTC7.Ashleigh%20Banfield.explosions.mp4).

David Chandler has conducted some audio analysis on these events, which I believe you’ll find intriguing. I’d love to hear your expert thoughts on his findings. (https://911warroom.com/wtc7/explosions/WTC7.Sound.Evidence.for.Explosions.mp4).

Additionally, the International Center for 9/11 Justice’s paper on WTC 7 from last year carefully documents the timing of these explosion sounds. David Chandler’s analysis is mentioned in Section 5.1 (Seismic, Audio, and Eyewitness Evidence), specifically in "Table 2: Times of Apparent Explosions in Relation to Collapse Events." I’ve attached that section below and linked the entire paper for your convenience: (https://ic911.org/journal/articles/the-instantaneous-free-fall-of-world-trade-center-building-7-and-nists-attempt-to-hide-it/).

Your expertise would really help in making sense of these critical moments. Thanks so much for your time, I would really appreciate it if you would consider looking into this!

Kind regards,  
Gene
gene@laratonda.com
724.826.1001

5.1 Seismic, Audio, and Eyewitness Evidence

The detonation of demolition devices over a period of about eight seconds is supported by seismic, audio, and eyewitness evidence as well as by the “severe erosion” found in “several beams” from WTC 7 (FEMA, 2002, Appendix C), indicating the use of thermite-based devices.

In Appendix B of NCSTAR 1-9, NIST documents two seismic events recorded at the Lamont-Doherty Earth Observatory 34 kilometers away from Lower Manhattan: one at 5:20:42 PM, corresponding roughly to the collapse of the east penthouse, and one eight seconds later at 5:20:50 PM, corresponding roughly to the initiation of global collapse. An abridged version of Table B-4 from Appendix B is presented below, showing NIST’s listing of these seismic events.

29. nist ncstar 1 9 table b 4

NIST attributes the first seismic signal to “interior debris falling to the lower floors of WTC 7 on the east side, which transmitted loads to the foundation,” and the second seismic signal to “the fire-damaged and buckled floors [moving] downward as a single unit, transmitting impact loads to the foundation.” These explanations strain credulity.

As geophysicist Andre Rousseau testified for the 2020 request for correction, the notion that sinterior debris falling to the lower floors inside one corner of the building could generate seismic activity sufficient to propagate 34 kilometers is simply impossible. It also contradicts NIST’s own claims about the seismic activity generated during the collapse of WTC 1 and 2, where NIST asserts that the collapsing structures — much greater in mass and force — generated no seismic activity until the debris started hitting the ground (NCSTAR 1-5A, pp. 22-24). (In reality, neither of NIST’s explanations for the recorded seismic activity — in the case of WTC 1 and 2, debris impacting the ground, or in the case of WTC 7, debris impacting the lower floors of the building — have been found to be sound (MacQueen, 2009; Rousseau 2012).)

Indeed, NIST is unable to explain why scattered falling debris, whether inside or outside the building, would generate sudden, powerful spikes of seismic activity when it involves a gradual, diffuse percussive force. NIST itself points to the oddity of the second signal being generated specifically at the onset of global collapse and not after, stating:

“One would have expected seismic signals from this second phase of collapse to be generated over this entire episode (which lasted approximately 14 s) since debris was continuously impacting the ground either unobserved within the core or externally as seen from the videos of the perimeter walls. However, because the total energy dissipated by the impact was distributed over a long period of time, the strength of the signal at any given time was small and difficult to interpret” (NCSTAR 1-9, p. 675).

In fact, in the case of the second seismic signal, its timing of 5:20:50 PM actually precedes NIST’s best estimate, based on television broadcasts, of when WTC 7’s downward motion began, which was at 5:20:52 PM (NCSTAR 1-9, p. 90). Why would a seismic signal be generated prior to the initiation of global collapse when the majority of the collapsing structure impacting the ground after global collapse initiation would be expected to generate much more seismic activity? A seismic event immediately preceding WTC 7’s downward motion is far more consistent with the synchronized detonation of demolition devices. A seismic event corresponding to the collapse of the east penthouse eight seconds earlier is also far more consistent with the detonation of demolition devices than with debris falling to the lower floors of the building (Architects & Engineers for 9/11 Truth, 2020, Section F and Exhibit B).

The seismic evidence is corroborated by various eyewitness and audio evidence of explosions at the onset of and during WTC 7’s collapse. Two examples of eyewitness reports that were given on the day of 9/11, immediately after the event, are provided below. The first report is notable because the witness explicitly identified the event as an explosion and she confirmed her account to one of the authors of this paper (Walter) in 2021. The second report is notable because it is consistent with the approximately eight-second demolition process indicated by the video and seismic evidence.

  1. NY1 reporter Gigi Stone Woods, who at the time of WTC 7’s collapse at 5:20 PM was stationed at the intersection of West Broadway and Reade Street, approximately 360 meters north of WTC 7, reported at 6:30 PM:

“…possibility that the fire was going to get worse. All of a sudden, a loud, incredibly loud explosion. And we have the video to show you” (NY1, 2001).

Ms. Woods confirmed her account in an email to Walter in January 2021, stating:

“Yes I am the reporter in that video. All I remember is that we were reporting near building 7 [sic] heard a loud explosion and people yelling to run and we all did. Except for a very brave cameraman Basche who stayed put and videotaped the building going down.”

  1. NYU medical student Darrell, who was interviewed twice on 1010 WINS Radio shortly after the event, stated:

“Yeah, so I was just standing there. We were watching the building actually because it was on fire. The bottom floors of the building were on fire. And, you know, we heard this sound that sounded like a clap of thunder. Turned around. We were shocked to see that the building was — well, it looked like there was a shockwave ripping through the building, and the windows all busted out. It was horrifying. Then, you know, about a second later the bottom floor caved out. And the building followed after. We saw the building crash down all the way to the ground.”

“We were just standing there. All of a sudden, out of nowhere, you hear this clap, sounds like thunder. The building had shockwaves going through it. You could see a shockwave go up the — the windows blast out. You know, I thought I was watching a movie. I mean, I can’t believe this is happening. It’s really ridiculous. But, you know, it came down floor by floor. The structure stayed intact until it all hit the ground” (1010 WINS, 2001).

The most notable piece of eyewitness and audio evidence for the purpose of corroborating our hypothesized timing of the column failure sequence is contained in a video recording of MSNBC’s Ashleigh Banfield witnessing the collapse (MNSBC, 2001). According to NIST, which examined this clip in its report, this footage was filmed at the corner of West Broadway and Leonard Street, approximately 650 meters north of WTC 7 (NCSTAR 1-9, p. 280).

30. banfield wtc 7
Figure 15: Ashleigh Banfield and a woman being interviewed turn toward WTC 7 roughly 650 meters to the south.

In the video, Banfield and others around her hear a loud sound — from more than seven football fields away — that causes them to quickly and involuntarily turn toward WTC 7. She then exclaims, “Oh my god. Look behind us. Please pan in this way. Be careful of your baby. This is it!” A man in the background then says, “That’s the building coming down,” just as the crowd noise quickly crescendos, which can be interpreted as the approximate time that WTC 7 begins to descend. Analysis of the video’s audio track performed by Chandler in 2010 revealed what appear to be nine separate explosions — first two initial explosions, relatively spaced out, and then seven more explosions regularly spaced over a span of 2.5 seconds (Chandler, 2010).

The roof of WTC 7 cannot be seen in the distance in the Banfield video, but by correlating the Banfield video with the video that NIST labels “Camera 4” — which was filmed at the same intersection and shows the global collapse but does not show the collapse of the east penthouse — we were able align the crescendo in the crowd noise heard in both videos. From there, we were able to deduce the exact time in the Banfield video that WTC 7 begins to descend, which then allowed us to identify the times that each explosion and Banfield’s reaction were recorded in relation to the start of the descent. Then, to determine an origin time of the sounds, we added 1.92 seconds to account for the time the sound took to travel 650 meters. (NIST performed this same analysis but reached a different time for Banfield’s reaction in relation to the start of the east penthouse collapse, approximately two seconds earlier than our time. We suspect this is because NIST assumed a 6.9-second interval between the start of the east penthouse collapse and the start of the roofline’s downward motion — as opposed to the correct 8.2-second interval — and because NIST may have failed to account for the one-second lag between the start of downward motion and the crescendo in the crowd noise. Although NIST studied this video, it did not identify the series of nine explosions identified by Chandler in his 2010 analysis.)

From the above analysis, we determined that the first explosion picked up on the Banfield video, accounting for the travel time of the sound, occurred 0.52 seconds prior to the start of the east penthouse collapse (corresponding to our estimated failure time for Columns 79 and 80); the second explosion occurred 0.22 seconds prior to the start of the east penthouse collapse; and the series of seven evenly space explosions occurred from 0.84 to 2.68 seconds after the start of the east penthouse collapse. Meanwhile, Banfield began to turn toward WTC 7 at 3.37 seconds after the start of the east penthouse collapse (not at 1.3 seconds, as claimed by NIST). Accounting for 1.92 seconds of sound travel, Banfield and the people around her must have been responding to the explosions that occurred in the range from 0.52 seconds before to 1.45 seconds after the start of the east penthouse collapse.

NIST’s Camera 3 video also picked up an apparent explosion that preceded the east penthouse collapse. Approximately one second prior to the start of the east penthouse collapse, a low but concussive boom, with a sudden acoustic onset, can be heard on the audio track. Accounting for a sound travel time of approximately 1.88 seconds, this apparent explosion occurred about 2.91 seconds prior to the start of the east penthouse collapse. We do not know why this apparent explosion was picked up by NIST’s Camera 3 but apparently not by the Banfield camera (we did examine the Banfield video for signs of earlier booms), nor do we know why the series of explosions picked up by the Banfield camera was not picked up by Camera 3. We find it entirely reasonable that different explosions would be picked up by different cameras, and we note that there may have been explosions that were not picked up at all.

Table 2 below presents the origin times of the apparent explosions captured in both videos in relation to the start of the east penthouse collapse, the north screen wall and west penthouse collapse, and the global collapse.

Table 2: Times of Apparent Explosions in Relation to Collapse Events
Event Start Time
Camera 3 Explosion -2.91 s
First Banfield Video Explosion -0.52 s
Second Banfield Video Explosion -0.22 s
Start of East Penthouse Collapse 0.0 s
Start of Seven-Explosion Sequence in Banfield Video 0.84 s
End of Seven-Explosion Sequence in Banfield Video 2.68 s
Start of Ashleigh Banfield’s Turn Toward WTC 7 3.37 s
Start of North Screen Wall and West Penthouse Downward Motion 7.4 s
Start of WTC 7 Downward Motion (Free Fall) 8.1 s*
Start of Crescendo in Crowd Noise 9.27 s
*8.1 s is the start of downward motion derived from the Camera 3 footage, which we then applied to the Camera 4/Banfield camera analysis.

Overall, the interval between the origin time of the first detected explosion in the Banfield video and WTC 7’s downward motion was approximately 8.6 seconds, while the interval between the origin time of the explosion in the Camera 3 video and WTC 7’s downward motion was approximately 11 seconds. Accounting for the likelihood that the final explosions occurred just prior to global collapse, this means the series of explosions lasted up to 10 seconds. Keeping in mind the margin of error inherent in all of the various measurements and the fact that an explosion does not necessarily produce seismic activity or observable structural behavior, the apparent series of explosions lasting up to 10 seconds is substantially consistent with the video observation of the east penthouse and the roofline beginning to descend 8.2 seconds apart and with two seismic signals being generated approximately eight seconds apart.

References

Author Information

  • David Chandler: B.S., Physics, Harvey Mudd College, Claremont, CA. M.A., Education, Claremont Graduate University, Claremont, CA. M.S., Mathematics, California Polytechnic University, Pomona, CA. Board member of the International Center for 9/11 Justice, which is affiliated with the Journal of 9/11 Studies.
  • Ted Walter: Master of Public Policy, University of California, Berkeley, CA. Executive director of the International Center for 9/11 Justice, which is affiliated with the Journal of 9/11 Studies.