Unlawful Interference Boeing 767-222 N612UA, Tuesday 11 September 2001
ASN logo

Date:Tuesday 11 September 2001
Type:Silhouette image of generic B762 model; specific model in this crash may look slightly different    
Boeing 767-222
Owner/operator:United Airlines
Registration: N612UA
MSN: 21873/41
Year of manufacture:1983
Total airframe hrs:66647 hours
Cycles:17569 flights
Engine model:Pratt & Whitney JT9D-7R4D
Fatalities:Fatalities: 65 / Occupants: 65
Other fatalities:900
Aircraft damage: Destroyed, written off
Category:Unlawful Interference
Location:New York, NY -   United States of America
Phase: En route
Nature:Passenger - Scheduled
Departure airport:Boston-Logan International Airport, MA (BOS/KBOS)
Destination airport:Los Angeles International Airport, CA (LAX/KLAX)
Investigating agency: NTSB
Confidence Rating:
In a massive coordinated terrorist attack 19 men hijacked 4 jetliners on the morning of September 11. The hijackers were on a suicide mission and had received orders to take over control of the aircraft and to fly the planes into specified targets.
United Airlines Flight 175 departed Boston-Logan for Los Angeles at 08:14. The aircraft was hijacked by five terrorists. The hijackers took over control, reportedly switched off the transponder and changed course to New York. At 09:03 the aircraft was flown into the Southeast side of the 110-story New York WTC South tower in a sharp left wing low attitude, crashed and exploded into the 78th through 84th floors. According to an FAA study, N612UA struck the WTC at a speed of 586 mph; an MIT study however determined the plane was probably traveling at 537 mph.
The massive fire weakened the tower structure on these floors and the tower collapsed at 09:59. Most of the office workers below the 78th floor were able to evacuate the tower on time before the collapse. Seventeen minutes before Flight 175 crashed into the South Tower, the WTC North Tower had been hit by an American Airlines Boeing 767, N334AA.
A total of 2,606 people were killed in the World Trade Center buildings, including about 292 on the ground. A precise breakdown of the number casualties relating to Flight 11 (North Tower) and Flight 175 (South Tower) is impossible.
It has been estimated that about 1600 people were killed on the North Tower, and about 900 on the South Tower.

Accident investigation:
Investigating agency: NTSB
Report number: DCA01MA063
Status: Investigation completed
Duration: 4 years and 5 months
Download report: Final report


USA Today
ATC transcript United Airlines Flight 175 / NTSB
Final Report of the National Commission on Terrorist Attacks Upon the United States
Flight Path Study United Airlines Flight 175 / NTSB


  • 2nd worst accident in 2001
  • 2nd worst accident of this aircraft type
  • worst accident of this aircraft type at the time



photo (c) FEMA; New York, NY; 11 September 2001

photo (c) James Covington; Los Angeles International Airport, CA (LAX); August 2001

Revision history:


The Aviation Safety Network is an exclusive service provided by:
Quick Links:

CONNECT WITH US: FSF on social media FSF Facebook FSF Twitter FSF Youtube FSF LinkedIn FSF Instagram

©2024 Flight Safety Foundation

1920 Ballenger Av, 4th Fl.
Alexandria, Virginia 22314