Embraer EMB-120 RT N221YV
21 July 1992 · Denver, Colorado, United States · No injuries
Summary
On 21 July 1992 at about 23:45 local time, a Embraer EMB-120 RT registered N221YV, operated by Mesa Airlines, Inc., was involved in an incident near Denver, Colorado, United States. 26 people were on board and nobody was injured. The NTSB has published a probable cause for this accident; it is quoted in full below.
The record
- Date
- at 23:45
- Classification
- Incident
- Location
- Denver, Colorado, United States
- Nearest airport
- Stapleton International (DEN)
- Coordinates
- 39.7609, -104.9201
- Aircraft
- Embraer EMB-120 RT
- Registration
- N221YV
- Category
- Airplane
- Engines
- 2
- Operator
- Mesa Airlines, Inc.
- Operating rule
- Part 135: Air Taxi & Commuter
- Purpose of flight
- Unknown
- Phase of flight
- Not recorded
- Route
- Durango → Unknown
- Aircraft damage
- Not recorded
- Weather
- VMC
- Light
- Day
- NTSB number
- DEN92IA074
People
Nobody was injured.
| On board | Died | Serious | Minor | Uninjured |
|---|---|---|---|---|
| 26 | 0 | 0 | 0 | 26 |
Probable cause
OPEN AIR GROUND CIRCUIT BREAKERS THAT ALLOWED THE PROPELLERS TO OVERSPEED. A FACTOR WAS: CLEAR AIR TURBULENCE.
Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.
Read the full NTSB narrative
THE CAPTAIN WAS FLYING THE AIRPLANE WITH HIS RIGHT HAND RESTING ON THE POWER CONTROLS. AS THE AIRPLANE TURNED ONTO FINAL APPROACH, IT ENCOUNTERED TURBULENCE OF SUFFICIENT INTENSITY THAT THE CAPTAIN'S FEET CAME OFF THE RUDDER PEDALS. HE FELT A 'CLICK' IN HIS HAND AND 'THERE WAS AN INSTANTANEOUS PROPELLER OVERSPEED.' THE ENGINE WAS EVENTUALLY SECURED BY CLOSING THE FUEL SHUTOFF VALVE AND AN UNEVENTFUL NO FLAP LANDING WAS MADE. POST INCIDENT EXAMINATION DISCLOSED BOTH AIR GROUND CIRCUIT BREAKERS WERE OPEN. THE LEFT ENGINE WAS FOUND TO BE FUNCTIONALLY DESTROYED. A READOUT OF THE DIGITAL FLIGHT DATA RECORDER DISCLOSED THE MAXIMUM LEFT AND RIGHT PROPELLER RPM VALUES ATTAINED WERE 150.49% AND 120.4%, RESPECTIVELY. VERTICAL ACCELERATION VALUES RANGED FROM .647 TO 1.26 G'S, AND LONGITUDINAL ACCELERATION VALUES RANGED FROM .037 TO .096 G'S. THE RIGHT ENGINE TORQUE PEAKED AT 37%, WHILE THE LEFT ENGINE TORQUE REMAINED AT 0%. RIGHT ENGINE FUEL FLOW WAS 16% TO 19% LOWER THAN LEFT ENGINE FUEL FLOW, AND PROPELLER IMBALANCE VALUES FOR THE LEFT ENGINE WAS APPROXIMATELY 50% HIGHER THAN THOSE RECORDED FOR THE RIGHT ENGINE.
Quoted verbatim from the NTSB record.
Other Embraer EMB-120 accidents
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 29 Apr 1993 | Embraer EMB-120 RT | Pine Bluff, Arkansas, United States | Continental Express | Minor injuries | - |
| 9 Apr 1990 | Embraer EMB-120 | Gadsden, Alabama, United States | Atlantic Southeast | Fatal | 2 |
| 25 Aug 1990 | Embraer EMB-120 | College Station, Texas, United States | - | No injuries | - |
| 18 Jul 1995 | Embraer EMB-120 RT | Los Angeles, California, United States | West Air Commuter Airlines Inc | No injuries | - |
| 14 Jul 1987 | Embraer EMB-120 | Atlanta, Georgia, United States | Atlantic Southeast Airlines | No injuries | - |
| 23 Jan 1987 | Embraer EMB-120 | Springfield, Missouri, United States | - | No injuries | - |
Other accidents in this area
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 12 Apr 1992 | Cessna 310-L | Hugo, Colorado, United States | Bell, Anthony H. | No injuries | - |
| 4 May 1992 | Boeing 757-222 | Denver, Colorado, United States | United Airlines | Fatal | 1 |
| 8 Jul 1992 | Piper PA-34-200T | Lamar, Colorado, United States | Lyddon Flying Service | No injuries | - |
| 4 Jan 1992 | Cessna 152 | Falcon, Colorado, United States | Patrick Clayton | No injuries | - |
| 16 Jan 1992 | Cessna 172P | Englewood, Colorado, United States | P.c. Flyers, Inc. | No injuries | - |
| 27 Jan 1992 | Cessna 172P | Englewood, Colorado, United States | P.c. Flyers, Inc. | No injuries | - |