Post by POA on Apr 13, 2004 0:40:25 GMT -5
This is one of the unmentioned questions of the dominant story of 9/11. All airplanes that have IFF systems installed also have the capability of having a signal sent out from their transponders set to a universal code displayed on radar monitors elsewhere that reads as 7500 and always signifies that a plane has been hijacked. Presumably, all of the pilots of the respective planes that were hijacked on 9/11 were also experienced enough to know how to switch to their IFF to 7500 rapidly if they ever were hijacked.
Yet, there are several anomalies in terms of IFF as far as 9/11 are concerned:
Anomaly 1: Out of all of the planes hijacked, only one out of the four had either pilot or copilot that reacted in time to turn on the 7500-universal hijacking code. You’ll note in timelines presented for 9/11 that present any IFF information they record that IFF was turned off-not that a 7500 was ever sent.
Anomaly 2: None of the black boxes possessed by any of the planes survived. One of the pieces of electronic data that all black boxes record is their IFF data.
An IFF primer:
According to here(1):
THE BLACK BOXES
And even if we forget the steel, there's the curious incident of the planes' black boxes - not ONE of the EIGHT black boxes - two per plane - survived! Not just those of the planes that crashed into the Twin Towers, but also of the other two planes! Not even of the one that crashed into the ground in Pennsylvania.
Do you know the kind of crash these black boxes are designed to withstand? The National Transportation Safety Board (NTSB) web site gives valuable information regarding these devices.
Regarding the Cockpit Voice Recorder it says:
"The CVR records the flight crew's voices, as well as other sounds inside the cockpit. The recorder's "cockpit area microphone" is usually located on the overhead instrument panel between the two pilots. Sounds of interest to an investigator could be engine noise, stall warnings, landing gear extension and retraction, and other clicks and pops. From these sounds, parameters such as engine rpm, system failures, speed, and the time at which certain events occur can often be determined. Communications with Air Traffic Control, automated radio weather briefings, and conversation between the pilots and ground or cabin crew are also recorded." [NTSB web site]
Regarding the Flight Data Recorder it says:
"The FDR onboard the aircraft records many different operating conditions of the flight. By regulation, newly manufactured aircraft must monitor at least twenty eight important parameters such as time, altitude, airspeed, heading, and aircraft attitude. In addition, some FDRs can record the status of more than 300 other in-flight characteristics that can aid in the investigation. The items monitored can be anything from flap position to auto-pilot mode or even smoke alarms." [NTSB web site]
Thus as we see each plane is equipped with two separate "Black Box" devices which relay different yet complimentary information.
It goes on to say:
"Both the Flight Data Recorder and the Cockpit Voice Recorder have proven to be valuable tools in the accident investigation process. They can provide information that may be difficult to obtain by other means." [NTSB web site]
They are meant to be the hardy and sure way to get information regarding the last minutes before the plane went down.
Here are the specifications of these devices including what they can withstand:
FLIGHT DATA RECORDER
Time recorded: 25 hour continuous
Number of parameters: 5 - 300+
Impact tolerance: 3400Gs /6.5ms
Fire resistance: 1100 degC/30 min
Water pressure resistance: submerged 20,000 ft
Underwater locator beacon: 37.5 KHz
Battery: 6yr shelf life 30 day operation
COCKPIT VOICE RECORDER
Time recorded: 30 min continuous, 2 hours for solid state digital units
Number of channels: 4
Impact tolerance: 3400 Gs /6.5ms
Fire resistance: 1100 deg C /30 min
Water pressure resistance: submerged 20,000 ft
Underwater locator beacon: 37.5 KHz
Battery: 6yr shelf life 30 day operation
These specifications indicate equipment which can survive just about any conditions and any crash. Indeed, Black Boxes have been recovered from crashes in swamps, mountains, and oceans.
ABC News reports:
"Although investigators look for an entire black box, sometimes the only parts of the device that survive are the recorder's crash-survivable memory units (CSMU). the csmu is almost indestructible. It is housed within a stainless-steel shell that contains titanium or aluminum and a high-temperature insulation of dry silica material." "It is designed to withstand heat of up to 2,000 degrees fahrenheit for one hour, salt water for at least 30 days, immersion in a variety of liquids such as jet fuel and lubricants, and an impact of 3,400 G's. By comparison, astronauts are typically exposed to up to six Gs during a shuttle takeoff." [ABCNews]
So the Black Box is designed to withstand an impact of 3,400 G's. So what about the Pennsylvania crash site?
"The voice recorder was said to be heavily damaged, and the manufacturer was being asked to help with further analysis. The plane that crashed in Pennsylvania was reported to have hit the ground in excess of 500 miles per hour." [ABCNews]
The plane hit the ground at 500 mph. Taking the weight of the plane, its speed of descent, the G's end up much, much lower than 3,400.
Since each plane has two separate Black Boxes which are designed to be indestructible in the event of a tragedy, that makes a total of eight black boxes. We are to believe that all the Black Boxes were damaged beyond use, while a measly paper passport survived!
So, with all of that being said, here’s what I think happened:
The hijackers had been followed well in advance of 9/11. Between them, it had also been worked out exactly who would go on which plane, and the agents/persons that had been following them also knew this information. So, someone in the federal government who knew the response times of the fighters and that they would be scrambled in the event of a hijacking decided to give them a little help.
This occured through the substitution of the IFF transponders in the planes. This act would have been hidden as normal maintenance on them. These altered IFF transponders were designed to transmit (‘squawk’) a standard code when 7500 was entered by the pilots, but would provide no indication, upon inspection by the pilots, that there was anything wrong with them whatsoever.
9/11 started. The pilots did exactly what they were taught to do-that is, they entered a 7500 on their transponders, but a normal code is sent out. This also would go a long way in explaining the discrepancies in the response time to the hijackings. The planes appeared to be perfectly normal until either the IFF was turned off, or until the hijackers themselves called in.
(A similar explanation is that no black boxes were ever found because there were no ‘black boxes’ even on the planes involved in the hijackings.)
Additional unasked questions:
1) When were the IFF transponders in the hijacked planes last exchanged or maintained?
2) Who was responsible for the maintainance on the IFF transponders?
3) Is there any video footage of the individuals who last did maintainance of the IFF transponders, or any record of their status with the airline company?
(Also curiously along these lines, a corporation associated with Marvin Bush, another presidential brother, did security work for United Airlines.)
4) Where are the black boxes? Where was the purported wreckage of the planes where no 7500 signal was transmitted laid out, and in any of the photographs or object records, is there any evidence that the black boxes ever existed in them?
(1) www.themedianews.com/DAGGER/Front%20Page/9-11_black_boxes_.htm
