The report was issued Tuesday at the start of a hearing into the emergency response to the terrorist attacks, setting the stage for two days of dramatic testimony at the New School University, about 1½ miles from ground zero.
The hearing began with a stark warning from the commission's staff: "The details we will be presenting may be painful for you to see and hear."
Within 20 minutes, family members of the trade center victims were dabbing their eyes and offering each other support. More than 2,700 people were killed in the attack.
Committee member Sam Casperson, in a minute-by-minute recounting of the second plane's crash into the World Trade Center, detailed how Port Authority workers were advised to wait for assistance on the 64th floor — and many of them died when the tower collapsed.
Communications breakdowns also prevented announcements to evacuate from reaching civilians in the building, Casperson said. One survivor of the attacks recounted calling 911 from the 44th floor of the south tower, only to be placed on hold twice.
Emergency 911 operators had a "lack of awareness" about what was happening at the twin towers, and were overwhelmed by the sheer volume of calls, Casperson said.
There were scores of family members in the audience as the commission showed footage of the first hijacked plane slamming into the tower, and played videotaped testimony from survivors. Videotape of the second plane's impact was shown as well.
Survivor Stanley Pranmath recounted sitting in his 81st-floor office as the second plane veered toward his building, so close that he could clearly make out the letter "U" on the tail of the United Airlines plane.
"I dropped the phone, screamed and jumped under my desk," he said, adding that rubble from the crash landed within 20 feet of his impromptu hiding place.
Revisiting the jarring sights and sounds of the attack and its aftermath was a vivid departure from previous commission hearings. Some of the videotapes showed the confusing, rushed recovery efforts.
One critical issue — early public address announcements in Tower 2 telling workers to remain at their offices — was recounted verbatim by a survivor.
The 26-page staff report reconstructing events through first-person survivor accounts found:
While many of the safety procedures put in place after the 1993 attack on the World Trade Center helped employees escape, others proved ineffective or possibly even dangerous in response to a very different type of attack eight years later.
One survivor, Brian Clark, president of Euro Brokers Relief Fund, said the PA system advised: "Your attention please, ladies and gentlemen, Building 2 is secure. There is no need to evacuate Building 2. If you are in the midst of evacuation, you may use the re-entry doors and the elevators to return to your office. Repeat, Building 2 is secure."
The report offers no concrete explanation for that direction. But it does suggest two possible reasons: a concern for workers being injured by falling debris from the other tower, and the knowledge that in the 1993 bombing, many of the injuries were sustained in the crowded evacuation of the building.
Those testifying at the hearings include current and former officials of the Port Authority of New York and New Jersey, the New York fire, police and emergency management departments, the Homeland Security Department and the Arlington, Va., fire department. Former Mayor Rudolph Giuliani was to testify Wednesday.
In the years since the attacks, a rising chorus of New Yorkers has demanded a tough-minded probe of the city's emergency response, a public airing of shortcomings that would assign responsibility for a series of systemic flaws.
"There are questions that have to be answered," said Bill Doyle, who lost his son in the trade center attack. "We can't bring our loved ones back, but we can have peace of mind that someone's being held accountable."
While the report does find fault in a few instances, it largely sympathizes with officials and rescue personnel forced to improvise in the face of an overwhelming catastrophe.
The commission also scrutinized the long-standing rivalry between the NYPD and the Fire Department, saying that in many instances the two agencies did not communicate effectively or quickly.
On the day of the attacks, neither agency "had demonstrated the readiness to respond to an incident commander" from another department, the report concluded.
Before Tuesday's hearings got underway, commission chairman Thomas Kean told CBS News' The Early Show, "No one could have anticipated in this, the greatest city of the world, we would have the greatest tragedy in the history of the country."
Kean said the panel would look at "what lessons there are, not only for New York City and its future, but for other cities in this country, that's the thing we're trying to get to. Lessons learned. Have we fixed the problem and what should we do in the future."
Last month, commissioners heard from President George Bush and Vice President Dick Cheney, former President Bill Clinton and ex-Vice President Al Gore, as well as national security adviser Condoleezza Rice, CIA Director George Tenet and Attorney General John Ashcroft.