Boeing 747SP N148UA
29 April 1991 · Churchville, New York, United States · No injuries
Summary
On 29 April 1991 at about 16:00 local time, a Boeing 747SP registered N148UA, operated by United Airlines, was involved in an incident near Churchville, New York, United States. 102 people were on board and nobody was injured. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.
The record
- Date
- at 16:00
- Classification
- Incident
- Location
- Churchville, New York, United States
- Coordinates
- 43.1005, -77.8796
- Aircraft
- Boeing 747SP
- Registration
- N148UA
- Category
- Airplane
- Engines
- 4
- Operator
- United Airlines
- Operating rule
- Part 121: Air Carrier
- Purpose of flight
- Unknown
- Phase of flight
- Not recorded
- Route
- Newark → Tokyo, Japan
- Aircraft damage
- Minor
- Weather
- VMC
- Light
- Day
- NTSB number
- NYC91IA133
People
Nobody was injured.
| On board | Died | Serious | Minor | Uninjured |
|---|---|---|---|---|
| 102 | 0 | 0 | 0 | 102 |
Probable cause
A FAILURE OF THE SIXTH ROTATING AIRSEAL WHICH LED TO AN UNCONTAINED ENGINE FAILURE.
Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.
Read the full NTSB narrative
THE BOEING 747SP HAD JUST LEVELED OFF AT FL350 AND WAS ACCELERATING FROM M.81 TO M.85. DURING THE ACCELERATION, A VIBRATION WAS FELT IN THE COCKPIT AND CABIN. NO ABNORMAL ENGINE READINGS WERE OBSERVED. THE VIBRATION LASTED FOR ABOUT 2 MINUTES AND WAS FOLLOWED BY A LOUD BANG HEARD IN THE COCKPIT. THE NUMBER TWO ENGINE REVEALED A FAILED SIXTH ROTATING AIRSEAL. METALLURGICAL EXAMINATION OF FAILED AIRSEAL SHOWED FEATURES TYPICAL OF OVERSTRESS WITH NO INDICATION OF PREEXISTING CRACKS.
Quoted verbatim from the NTSB record.
Other Boeing 747 accidents
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 16 Jun 1991 | Boeing 747-400 | Philadelphia, Pennsylvania, United States | KLM Royal Dutch Airline | Serious injuries | - |
| 29 Dec 1991 | Boeing 747-200F | Taipei, Taiwan | China Airlines | Unknown | - |
| 22 Aug 1991 | Boeing 747-151 | Seattle, Washington, United States | Northwest Airlines, Inc | Minor injuries | - |
| 17 Oct 1991 | Boeing 747-300 | Houston, Texas, United States | KLM Royal Dutch Airline | No injuries | - |
| 13 Aug 1991 | Boeing 747-200 | Los Angeles, California, United States | Air New Zealand | No injuries | - |
| 24 Oct 1991 | Boeing 747-122 | Denver, Colorado, United States | United Airlines | No injuries | - |
Other accidents in this area
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 1 Jul 1991 | Maule M6-235 | Arcade, New York, United States | Haley, Lawrence E. | No injuries | - |
| 2 Jul 1991 | Cessna C-172 | Clarence Center, New York, United States | Augusta Aviation, Inc. | Minor injuries | - |
| 2 Jul 1991 | Piper PA-32R-300 | Rhinebeck, New York, United States | Catskill Transportation | No injuries | - |
| 14 Jul 1991 | Robinson R-22B | White Plains, New York, United States | Engle Helicopter, Inc. | No injuries | - |
| 17 Jul 1991 | Cessna 152 | Springwater, New York, United States | State Aerial Farm Statistics | No injuries | - |
| 12 Aug 1991 | Cessna 152 | Bear Mountain, New York, United States | Control Arrow, Inc. | Minor injuries | - |