Seismic Proof?
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The story...

Seismic stations around New York recorded events prior to impacts of Flight 11 and 175.  Is this documented proof of the basement explosions described by William Rodriguez and others?

Our take...

The claim appears in a Journal of 9/11 Studies paper:

On September 11, 2001, the seismic stations grouped around New York City recorded seismic events from the WTC site, two of which occurred immediately prior to the aircraft impacts upon the Twin Towers. Because these seismic events preceded the collisions, it is clear they were not associated with the impacts and must therefore be associated with some other occurrence. None of the authorities charged with the responsibility for the investigation of the events of 9/11 have proposed a source for these seismic events, nor have they given a valid reason for the difference in times between the seismic events and the aircraft impacts. Only by consideration of the evidence of basement explosions before the aircraft impacts, as experienced by William Rodriquez and 36 others, can an explanation be found for the fact that the seismic stations recorded seismic events originating from the WTC sites prior to the aircraft impacts. It seems unlikely that Middle Eastern terrorists could have overcome the WTC security and managed this kind of high-level, technological coordination. Do the facts presented here, simple and few, raise the possibility of inside involvement in 9/11/01, both before and after the attack?
Seismic Proof - 9/11 Was An Inside Job (Updated Version II)

It's based around the following anomaly. 

The Lamont-Doherty Earth Observatory (LDEO) timed the impacts of Flight 11 and 175 at 8:46:26 and 9:02:54, respectively, while the 9/11 Commission reports the impacts at 8:46:40 (14 seconds later) and 9:03:11 (17 seconds later). So if both times are accurate then what caused the mini earthquake recorded by LDEO?

The accuracy of the data is, of course, the first point to consider. The "Seismic Proof" paper points us to this statement from LDEO:

In case of the WTC attack, the impacts of the two planes could be determined with an accuracy of about [plus or minus] 2 seconds.

Nonetheless, as the paper also points out, the seismic data was reanalysed later and the times did change:

...These [seismic] signals have subsequently been reanalysed by LDEO, working under a contract for the NIST WTC Investigation (Kim, 2005). A reinterpretation of the types of seismic signals received resulted in slightly revised times for the major events. The results of this recent analysis are also included in Table 3-1...

[The new times were three seconds later than the old: 8:46:29 and 9:02:57]

Three seconds is a little closer, but not nearly enough to resolve the problem.

Meanwhile the Commission’s methods are explained here:

The Commission’s times are based upon:

"We have determined that the impact time was 9:03:11 based on our analysis of FAA radar data and air traffic control software logic." [9/11 Commission Report, pg 460, Note 130]...

It is known that the FAA followed the aircraft using the four northeast ARTCCs (Air Route Traffic Control Centers) of Boston, New York, Washington DC, and Cleveland; there was also Air Traffic Control for the local air space of New York City. All of this radar and accompanying Air Traffic Control data was recorded to UTC timestamping. These stations utilized primary radar return tracking with all times to the second. Also, an Air Traffic Controller replied to this investigation stating that a time-check is done daily by all stations to make sure that all radar tracking is precisely coordinated to UTC. Radar is based upon microwaves that travel at the speed of light, so error variance is not stated. The Commission Report has the impact times. Their data set is based upon actual flight data that ended when the Towers were struck. There is no question: AA Flight 11 died at 8:46:40 and UA Flight 175 at 9:03:11 [UTC – 4 hrs].
Seismic Proof - 9/11 Was An Inside Job (Updated Version II)

These appear to be solid claims, yet they raise immediate questions, and perhaps not the ones the authors intended. Take a look at the LDEO seismic chart, for instance:


Note that LDEO are reporting a single seismic event for each impact, not two. Are we to believe that a pre-impact explosion registered at LDEO, even more significantly than the impacts themselves?

Further, if there was an explosion of this power, then wouldn't you expect it be reported by rather more people? Here are just two relevant accounts:

When the first plane hit the North Tower on about the 90th floor it was nowhere near as dramatic as you would think on the 65th floor, just 25 floors down. There was a definite explosion but it did not sound that bad.
There was a big flash of light. The really scary part was how much the building moved, and kept moving, for a long time before re-stabilizing.
Bruce Stephen
WTC Survivor

...I heard a loud explosion, which was immediately followed by tremendous building sways and vibrations. As I was thrown out of my chair, I immediately thought that this was an earthquake, but still thinking rationally, I thought that it was abnormal since there are no earth-quakes in NYC, especially of this magnitude. I remember thinking that the building felt like it was going to collapse from this initial explosion.
Cary Sheih
WTC Survivor

If these accounts are describing the plane impacts, then what we're being asked to believe is that they didn't register seismically to any significant degree, despite causing effects comparable to an earthquake. And if they're describing a pre-collapse explosion, then we have to believe that they missed the plane hitting ten or more seconds later. This makes no sense to us. Of course there’s no reason our inexpert and unqualified guessing should carry any weight with you, but perhaps a closer examination of the data will reveal a more convincing explanation of what’s going on.

We could start by looking at the NTSB Flight Path study for Flight 11. That uses the 8:46:40 time, but describes it as "approximate". The Flight 175 document uses the same qualifier. As both studies relate to flight paths it's no great surprise that they wouldn't focus on impact time accuracy, however it would be useful to know how "approximate" they really are. Another NTSB document may offer some clues:

ASR radar normally records data approximately every 4 seconds, but ARSR data is only recorded every 12 seconds...

The accuracy of the radar returns decreases with increasing distance from the radar sites. Since the relative distances of all the radar sites are different, there is a differing amount of error in the position of the aircraft determined from each radar source. An effort was made to account for the error in each radar data set, such that the best alignment of all radar data sets was achieved...

Occasionally, the clock time of day recorded at the individual radar sites may not be consistent... The time of day at the airport ASR facilities is set at each facility, such that each ASR facility's radar data could have a slightly different time of day.

The 84th RADES found that the clock for the North East Air Defense Sector (NEADS) lagged the clocks for the other sectors by 25.3 seconds... The other sectors were all in agreement with the Global Positioning Satellite (GPS) time...

Comparison of the altitude data from the various NTAP centers and RADES showed no offset in time required for the FAA data from Washington, Cleveland, and Boston centers. An offset of 8 seconds was corrected in the NTAP radar data from New York to align with the time of day from the RADES and other center NTAP radar data sets...

Although "Seismic Proof" earlier portrayed the radar times as accurate "to the second", the NTSB paint a very different picture. The radars didn't all use synchronised times, for instance, and in this case there were large offsets to be considered. An "effort" had to be made to account for the "error" in each radar set. And as they point out, ASR radar doesn't provide continuous data anyway: records are made "approximately every 4 seconds". 

The NTSB nonetheless did devise a system to correlate all these times. Here’s what they had to say:

A time correlation was made between the RADES radar data, NTAP radar data, ASR radar data sets, FDR data (when available), and Air Traffic Control (ATC) radio transmission transcript data. Times indicated with the USAF RADES radar data were used as the reference time, and the FDR and ATC clocks were adjusted accordingly. Times given in this report are in 24-hour format, in the form HH:MM:SS Eastern Standard Time (EST). The FDR records information relative to an elapsed time in seconds, and are assigned a time of day using the technique outlined below.

A comparison of the radar altitude versus local time for the several radar data sets with the FDR data (UAL83 [sic] and AA77) provided the basis for correlating the respective FDR data to the time of day. FDR altitude versus elapsed time were was transposed to the radar data time of day using a single anchor point, i.e. a a specified number of elapsed seconds on the FDR = 00:00:00 EDT. This anchor point is different for each FDR, and is further verified using radio callouts on the ATC transcript and microphone keying on the FDR.

As discussed in a previous section, transponder altitude data was recorded from several radar facilities. All of the radar systems from the USAF RADES utilized the same time of day clock, and this time of day was also consistent with the adjusted NTAP and ASR radar time of day. After the correlation was applied to the FDR data, the ATC transcript provided an additional check of the correlation for the radio transmissions. All the FDR and radar data in this report are given in the correlated local time (EDT). Refer to the FDR Factual Report for FDR data extracted for UA flight 93 and AA Flight 77.

This is an impressive-sounding process, however any uncertainty in the resulting times is not spelled out. The NTSB didn’t have flight data recorder (FDR) data for Flight 11 and 175, either, so their calculations would not have this additional extra check. Presumably that would increase any resulting uncertainty in times for those flights, but to what? We don’t know. And this matters, so if you’ve not done so already, go read the entire document above to make sure you’re getting the whole picture.

Our view is that the correlation process they’re describing does have plenty of scope here for errors of considerably more than a second. Views here really don’t matter at all, of course, but without a clear statement on uncertainty of the accuracy time from the NTSB, and with no access to the raw data, it's hard to see how we (or anyone else) can assess the accuracy of this calculation.

Fortunately there are other ways to at least determine the time of the second impact. This was captured on many news broadcasts, the footage of which included a clock. NIST used this to determine the impact time, and reported the results here:

Many of the news broadcasts on September 11, 2001, had the current time imprinted on the screen. These imprints are known in the industry as "bugs". As these broadcasts were timed, it became apparent that there were small differences between times for the second aircraft impact based on these bugs and the time used as the basis for the database. Checks with several broadcasters indicated that the bugs should be quite close to the actual time because the clocks used as sources for the bugs are regularly updated from highly accurate sources, such as geopositioning satellites or the precise atomic-clock-based timing signals provided by NIST as a public service. Careful checks showed small time differences between different video recordings, but these were generally less than 1 s. These small discrepancies were likely due to variations in transmission times resulting from the different pathways that the video signals took to the sites where they were recorded. Based on four independent video recordings, the actual time of the second aircraft impact was determined to be 9:02:59 a.m., or 5 s later than the time assigned in developing the database. The estimated uncertainty is 1 s.

This puts the impact five seconds after the original LDEO time, but only two seconds away from the revised time, within the combined margin of error. No support here for an impact as late as the Commission time of 9:03:11. Some may object to this analysis, especially as it’s come from NIST. If you don’t trust their report, then why believe them on this? 

One answer is to locate videos of the second impact, and check the time shown. This poses some problems of its own, because there’s no way to tell whether videos you download from a 9/11 site (including this one) are genuine and unaltered in every aspect, and you need a better chain of custody than that. However, as we write (December 2006) the station NY1 has a link where you can watch footage from their 9/11 coverage, including a clip that shows the explosion from the second impact.


See the station’s footage here (Real format)
View our snipped clip here (AVI with XViD codec)

Their clock had changed over to 9:03 around half a second before the explosion began to be visible. When you consider that the explosion didn’t occur immediately on impact, and there could be a delay in broadcast anyway (the time it takes a video frame to be processed, leave the camera, and be sent to the studio before the time stamp is added), NIST’s 9:02:59, with a one second uncertainty, seems very close. 

There are those who suggest the broadcast footage has been faked, too, so perhaps this isn’t convincing enough. But that’s not a problem: we have still other sources available.

In August 2006, for example, a large number of 911 and other emergency calls from September 11th were released to the public. Each call was given a start time. The second call in the audio file for “Bronx Master Channel #3, Voice Alarm Telephone” is said to start at 09:02:54, and approximately 4.5 seconds into the call you hear shouting in the background, and the caller says there’s been a “major explosion in the second building”. (The list of all available files is here, the MP3 file we’re referring to is here, our snipped version of the second transmission only is here.)

Plainly we have an accuracy issue here: how much can we trust these times? Presumably emergency transmissions are more likely than most to be used in legal cases, and so would have to be timed very precisely, but that’s just a guess on our part, and they don’t say how accurate the times are. 

Further, while this time looks potentially very close to NISTs 9:02:59, other calls are a little further out. The one in this file appears to show reaction from behind the caller at around 9:03:04 to 05, for instance. Of course the speed of reaction from the viewers will depend on the coverage they’re watching: the above NY1 image, for instance, isn’t obviously a plane and it may have taken a moment for viewers to react, but if others watched a live shot where Flight 175 was visible then the story may have been different.  In any event, neither call appears to support the Commission’s 9:03:11 time.

This remains an “official” source, though. If you distrust NIST, and the TV networks, then maybe you’ll think these tapes might be faked, too. So it’s just as well there’s an independent source we can use by way of comparison.

On 9/11 Pavel Hlava was riding through New York, videotaping the WTC, when he briefly caught the first impact. After passing through the Brooklyn Battery Tunnel he continued filming the burning tower, and caught the second impact, too. But most important of all, there's a timestamp running throughout the footage. Here's what it shows.

Flight 11 has just penetrated the WTC here: Hlava has the time at 8:46:28 (actualy impact could be a second earlier). Download the video from this site, or grab our hosted copy here.


The second video has the precise point of impact concealed, but these two images should give you an idea.



Here the impact is around 9:02:57, within half a second or so. Confirm this for yourself by downloading a copy of the video from another site, or take a look at our copy here. (There’s more background in a New York Times Flash applet, which we’ve also archived here.)

For Flight 11, then, LDEO originally estimated an impact time of 8:46:26; revised it to 8:46:29; Havel gives us 8:46:28.

And for Flight 175, LDEO give us 9:02:54, and revised it to 9:02:57, while Havel gives us 9:02:57, the Bronx Channel #3 call gives us something before 9:02:58.5, and the NY1 clip says something before 9:02:59.5; NISTs “TV time” is 09:02:59.

The Havel timings have a fair degree of uncertainty, so please check the videos for yourself, but they do seem to match up with the LDEO very well. The way Havel’s shot of the second impact agrees with TV recordings and emergency call time further tells us that his camera clock wasn’t far from the real time. 

Combining these factors makes a strong case for the seismic events corresponding to the impact times, just as LDEO reported. We are left with a mystery in the apparent inaccuracy of the “FAA radar data and air traffic control software logic” calculation method used by the 9/11 Commission, however it seems its derived time cannot be used to prove pre-impact explosions at the WTC.

The only remaining fight is over the Havel footage. Because even though it appeared in 2003, before the 9/11 Commission Report was released, so could not have been faked to resolve a timing discrepancy that hadn’t occurred yet, there are still those looking to falsify it. Not least because independent footage of both impacts would make those who claim that no planes hit the WTC at all, look, well, completely wrong. And so there is a claim that something is “wrong” with the footage, as this page illustrates:


Apparently we’re supposed to believe the red and white “object” in the rear window of the highlighted car is a reflection of the vehicle that Havel is in; it’s not a black SUV, therefore we cannot trust his story. (Go visit the page to see this in motion, though it makes little difference to us.) 

One immediate and obvious problem with this is there’s no reason at all to believe it’s a reflection of Havel’s vehicle. In fact, from the position of the sun (see the shadows of the cars), this seems most unlikely. But more serious problems were revealed in a post on the physorg forum.

First, he identified the car model as a 1999 BMW Z3, with this picture.


(cropped from here)

Next, he pointed out the third red brake light visible at the top of the rear window, and suggested this is a likely cause of the red reflection.

And finally, he points to the steep angle of the rear window as a sign that any reflection would not be of an object directly behind it.


(original here)

Looks like a thorough rebuttal to us, though please visit the Webfairy page, view the Havel video, and make your own mind up.

Update: The PhysOrg forum has another post attempting to make the reflection idea stand up here. Keep reading from that post for the response.

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