On November 9, 1965, the largest blackout in history occurred. The northeast power system broke up 4 seconds after the initial disturbance, and 30 million people were without electricity for as long as 13 hours. Later that day, President Lyndon Johnson wrote to the chairman of the Federal Power Commission:
"Today's failure is a dramatic reminder of the importance of the uninterrupted flow of power to the health, safety, and well being of our citizens and the defense of our country.
"This failure should be immediately and carefully investigated in order to prevent a recurrence.
"You are therefore directed to launch a thorough study of the cause of this failure. I am putting at your disposal full resources of the federal government and directing the Federal Bureau of Investigation, the Department of Defense and other agencies to support you in any way possible. You are to call upon the top experts in our nation in conducting the investigation.
"A report is expected at the earliest possible moment as to the causes of the failure and the steps you recommend to be taken to prevent a recurrence."
Signed,
Lyndon B. Johnson
The Event
The Great Northeast Blackout of November 9, 1965 began at 5:16 p.m., near the end of an otherwise typical work day.
The event started at the Ontario - New York border, near Niagara Falls.
A single transmission line from the Niagara generating station tripped (opened).
Within 2.5 seconds, five other transmission lines became overloaded and tripped, isolating 1,800 MW of generation at Niagara Station.
After their isolation, the generators became unstable and tripped off-line.
The northeast power system became unstable and separated into isolated power systems (islands) within 4 seconds.
Outages and islanding occurred throughout New York, Ontario, most of New England, and parts of New Jersey and Pennsylvania.
Most islands went black within 5 minutes, due to imbalances between generation and load (generator overspeed/underspeed tripping).
The massive blackout left 30 million people without electricity for as long as 13 hours.
