1 World Trade Center
The September 11th Attack
WTC 1, or the North Tower, was the first of the Twin Towers to be completed, the first to be hit by one of the trans-continentially fuelled flights on September 11th, and the last to be destroyed.
|This frame is from the famous Naudet brothers' video.|
At 8:46 AM, Flight 11 slammed into the northeast face of the tower, creating an impact hole that extended from the 92nd to 98th floors. Upon impact, fireballs and smoke emerged from the building. The impact rocked the tower, causing a horizontal deflection of perhaps 10 feet on the upper floors, according to reports of some occupants. Flight 11 was carrying an estimated 10,000 gallons of fuel at the time of impact. There is only one known video, and no known photographs, capturing the moment of impact and subsequent fireball development. It shows orange fireballs and torrents of smoke possibly obscuring fireballs emerging from the punctured north wall and the east wall. The centered impact had embedded most of the plane in the tower's stout core, and fireballs fed by office air with atomized jet fuel spilled out of the punctured north wall and adjacent east wall. It is widely believed that most of the fuel remained inside the building and burned there. Unlike the South Tower impact, the only piece of plane documented to exit the North Tower was a small piece of landing gear (and supposedly a hijacker's passport).
For a few minutes after the impact fires could be seen on several floors, including most of the perimeter of one floor. By the time the South Tower was hit, less fire was visible from the Building's north side, and the smoke had turned darker, apparently due to the exhaustion of the jet fuel. As time progressed, the fires spread to new areas while burning out in others. Photographs show significant expanses of fires near the windows on several floors prior to the tower's destruction. A span about 40 feet wide at the 104th floor of the northwest face showed large emergent flames starting about the time that the South Tower fell.
Evacuation and Rescue
The evacuation of the North Tower proceeded efficiently from the time it was hit, via the three stairways. The elevators were all knocked out. The 102 minutes between the impact and collapse allowed the vast majority of its occupants below the crash zone to escape to safety.
No one on the 91st floor or above is believed to have survived. The New York Times estimated that 1,344 of the people in this zone perished. It is not clear how many remained alive until the collapse, but many parts of the upper floors filled with toxic smoke long before. In many cases people broke windows for fresh air. In one of the most horrifying spectacles of the attack, at least 37 and perhaps twice that number of people jumped to their deaths, apparently to escape agonizing deaths from smoke inhalation. 1
The light northerly wind kept the north corner of the roof clear of smoke, and helicopter rescue should have been possible. However the Port Authority had all the doors to the roof of the tower locked shut, despite the fact that helicopter pilots rescued 28 people from the tower's roof during the 1993 bombing. 2
At 10:07 a police helicopter radioed a warning for firefighters to evacuate the North Tower because the South Tower had just collapsed. Unfortunately most of the firefighters' radios did not work inside the towers, and few heard that or other orders to evacuate. 121 FDNY firefighters were killed when the North Tower collapsed. 3
The North Tower began its precipitous collapse at 10:28 AM. The collapse began in an instant, as the entire overhanging section of the tower began its telescoping plunge into the intact section. Although no flames had been visible in the crash zone for some time, a second after the collapse began, large orange flames bellowed out from the collapse zone. Within about two seconds, the exploding clouds of dust swallowed up the tower's top.
The sequences of destruction in WTC 1 and 2 looked very similar once the tops disappeared. The nature of those events is described in more detail in the features section of the collapse analysis, based on the surviving evidence.4 5
2. Could Helicopters Have Saved People From the Top of the Trade Center?, Wall Street Journal, 10/24/01 [cached]
3. Some Firefighters Could Have Been Saved, Emergency Medical Services, [cached]
4. FDNY Distress Call!, evesmag.com, [cached]
5. Terrorist Attack At New York World Trade Center, firehouse.com, 9/9/02 [cached]