II.

Terror from the Sky

The twin towers of the World Trade Center and the Pentagon were constructed to withstand attacks. But the organizers of the September 11 strike devised a plan that had not been anticipated and for which no effective defense had been prepared: to use a large fuel-laden commercial airliner as a highly explosive bomb. No trained airline pilot would willingly fly his or her aircraft into a building full of people, even at gunpoint, but the terrorists had a way around that problem. They would do it themselves, as part of a suicide mission.

After checking passenger lists for each of the hijacked flights and correlating names with passport records and other identity documentation, the Federal Bureau of Investigation (FBI) concluded that 19 men were involved in the hijackings, some as pilots and some as accomplices. Several had taken flight lessons in the United States. They needed only basic training to accomplish their mission: Since they planned to hijack planes already in flight, they did not have to learn takeoff procedures, and since they intended to crash, they did not need to know how to land.

Preparations for the mission seem to have been extensive. Officials later concluded that the tactical leader for the entire September 11 operation was an Egyptian named Mohammed Atta, who was apparently at the controls of one of the planes flown into the World Trade Center towers. He and the others who were to receive flight training arrived in the United States in 1999. In addition to learning to fly, the men are believed to have scouted potential routes and flights and traveled extensively around the country. Investigators later determined that large sums of money were transferred to the hijackers in installments at different points in 2000 and 2001. The accomplices for the operation arrived later. These men, who would be responsible for physically subduing crew members in the first moments of the hijackings, spent much of their time during the months preceding the hijackings working out in gyms.

The hijacking leaders eventually selected transcontinental flights from the East Coast to the West Coast, which meant that the aircraft would be carrying extra fuel. They chose flights on a midweek day that would be less likely to have a full load of passengers, meaning there would be less chance of someone interfering with their plans. Since U.S. airline screening procedures make it virtually impossible to smuggle guns aboard, the hijackers used pocketknives, utility box-cutting knives, and cans of Mace or pepper spray as their weapons.

A.

World Trade Center

The first two planes, American Airlines Flight 11 and United Airlines Flight 175, left Boston within minutes of each other, around 8 am. Both were Boeing 767s bound for Los Angeles, and they carried between them 137 passengers and 20 crew members. The first indication of trouble came at about 8:25 am, when air traffic controllers in Boston heard a strange voice from the Flight 11 cockpit saying, “We have some planes. Just stay quiet, and you will be OK. We are returning to the airport.” A few minutes later the plane turned off course, heading south toward New York City. Flight 11 crashed into the World Trade Center north tower at 8:46 am, hitting the 110-story building between the 93rd and 99th floors. The hijackers of United Flight 175 followed a similar route. Flying much faster, they slammed their airplane into the World Trade Center south tower, also 110 stories tall, between the 77th and 85th floors 16 minutes later, at 9:03 am.

New York firefighters rushed to the scene from stations across the metropolitan area and helped thousands of people evacuate the towers and buildings nearby. Nearly all of the World Trade Center workers caught in offices above the floors where the planes hit had no means of escape. Many, realizing they were doomed, jumped from their office windows rather than waiting to suffocate or burn to death.

The tower structures, built from 1966 to 1973, were designed to withstand the impact of a jetliner crash, and initially remained intact. However, Boeing 767s are much larger than 1960s-era jetliners, and carry much more fuel. In both towers the intense heat from the burning jet fuel eventually melted their interior steel supports. At 9:58:59 am the south tower collapsed: The steel supports gave way in the burning part of the tower, the floors above fell into the lower portion of the building, and the weight of the falling sections swiftly caused the lower floors to pancake. The north tower fell in a similar fashion 29 minutes later, at 10:28 am. More than 400 rescue workers, including more than 300 New York firefighters, were crushed in the ash and rubble. Including the World Trade Center workers who died and the aircraft crews and passengers, the total death toll in the New York attack was about 2,750.

B.

The Pentagon

American Airlines Flight 77, meanwhile, took off from Washington Dulles International Airport outside Washington, D.C., at about 8:20 am with 6 crew members and 58 passengers. Like the Boston flights, the airplane was bound for Los Angeles, and its fuel tanks were full. About 40 minutes later, the hijackers turned the Boeing 757 around and flew it back toward Washington, D.C. Flying low and fast, the airplane hit the Pentagon at 9:37 am. In a bit of good fortune, the plane crashed into the west side of the building, which had recently been reinforced with stronger construction and blast-resistant windows in order to withstand a terrorist attack. Even so, the plane penetrated three of the Pentagon’s five concentric rings, taking a chunk out of the building and incinerating dozens of offices and the people who worked in them. The plane’s burning fuel spilled through the ruins as military and civilian workers groped their way through smoky and burning offices to rescue colleagues. In all, 184 people died at the Pentagon, including everyone aboard the plane.

C.

“Let’s Roll”: Flight 93

The fourth aircraft hijacked on September 11, United Airlines Flight 93, took off from Newark, New Jersey, at about 8:40 am, bound for San Francisco. The Boeing 757 was the last of the four planes to be hijacked, and its passengers heard about the World Trade Center and Pentagon attacks through telephone conversations with family members or friends. Several male passengers, realizing what was happening, decided to rush the cockpit and try to wrest control of the aircraft away from the hijackers, even if it meant crashing. One passenger, Todd Beamer, told a telephone operator of the plan. After asking the operator to pray with him, Beamer set down the phone. The operator heard him say, “Are you ready?” Then, “OK, let’s roll.” It is unknown where the hijackers of Flight 93 intended to crash the plane, but the aircraft was headed toward the Washington, D.C., area when it crashed in a field near Shanksville, Pennsylvania, at about 10:03 am. The phrase “Let’s roll” would become a U.S. rallying cry in the subsequent war on terrorism.