Accident Boeing 737-3T0 N17356, Sunday 12 September 1999
ASN logo

Date:Sunday 12 September 1999
Type:Silhouette image of generic B733 model; specific model in this crash may look slightly different    
Boeing 737-3T0
Owner/operator:Continental Air Lines
Registration: N17356
MSN: 23942/1522
Year of manufacture:1988
Total airframe hrs:34602 hours
Engine model:CFMI CFM56-3B1
Fatalities:Fatalities: 0 / Occupants: 89
Other fatalities:0
Aircraft damage: Substantial, repaired
Location:West Palm Beach International Airport, FL (PBI) -   United States of America
Phase: En route
Nature:Passenger - Scheduled
Departure airport:West Palm Beach International Airport, FL (PBI/KPBI)
Destination airport:Houston-George Bush Intercontinental Airport, TX (IAH/KIAH)
Investigating agency: NTSB
Confidence Rating: Accident investigation report completed and information captured
A Boeing 737-300, operated by Continental Airlines as flight 1933, had a failure of the No. 1 engine shortly after takeoff from West Palm Beach.
The captain stated he was in the right seat and acting as a check airman. The second pilot, who was flying the aircraft from the left seat, was receiving initial operating experience as a captain. Both pilots stated that after takeoff on runway 9 left, as they were climbing through about 1,000 feet, there was the sound of a loud bang, they felt a extremely violent jolt, and felt severe shaking of a short duration. The No. 1 engine gauges went to zero. There was no indication of fire. The second pilot continued to fly the airplane and the captain ensured the No. 2 engine was increased to full power. They entered a left downwind leg for runway 9 left and returned to West Palm Beach International Airport, where they landed without further incident.
Examination of the airplane showed there was damage to the left wing high lift devices, fuselage, vertical and horizontal stabilizers, rudder, and tail cone. The No. 1 engine left thrust reverser had separated. Debris from the No.1 engine was located over an eight block long by three block wide city block area. Examination of the No. 1 engine revealed that it had a 360 degree separation in plane with the high pressure turbine (HPT) rotor and that the HPT shaft and the HPT forward rotating air seal had exited the engine. The HPT rotating air seal was recovered in the debris field.

PROBABLE CAUSE: "The fatigue fracture and separation of the high pressure turbine forward rotating air seal due to a manufacturing defect in a bolt hole that was not detected by the engine manufacturer due to inadequate and ineffective inspection techniques. Contributing to the accident was the engine manufacturers failure to provide adequate hole making requirements at the time the forward rotating air seal was manufactured and the engine manufacturers failure at the time of last inspection to require eddy current inspections for the high pressure turbine forward rotating air seal bolt holes."

Accident investigation:
Investigating agency: NTSB
Report number: MIA99FA252
Status: Investigation completed
Duration: 10 months
Download report: Final report


NTSB id 20001212X19822

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