Sources
Overview
- National Transportation safety Board
- Federal Aviation Administration
- Air Line Pilots Association
www.ntsb.gov/doclib/reports/2007/AA0701.pdf
www.faa.gov
www.alpa.org
- Flight History
- Causes of the Accident
- Human Factors
- Aerodynamic Factors
- Recommendations
- Conclusion
Pinnacle Airlines
Flight 3701
by: Travis Nelson
Andrew Porter
Recommendations
Flight History
- Improved high-altitude training in regional jet aircraft
- Require air carriers to provide high alt. operations training and stall recovery techniques in the simulator
- Verify that all Canadair regional jet operators incorporate guidance in their double engine failure checklist that clearly states the airspeeds required during the procedure
- Encourage engine manufacturers to perform research to find engines susceptible to core lock
and update flight manuals of the importance of a
minimum safe airspeed during restart
- Aircraft was on a re-location flight.
- Part 121 Operated on an IFR flight plan with cruise at 33,000 ft MSL
- Company provided flight plan
- The crew climbed to 41,000 ft MSL (maximum aircraft operating altitude)
- Both engines flamed out, were never re-started and the aircraft eventually impacted
the ground
High Altitude Stall
Human Factor:
Flight Crew Conduct
Engine Core Lock
Compressor stall/Flame-out
- Deviations from flight plan
- Climbing to FL410
- Deviations from standard operating procedures
- Company altitude restrictions above FL370
- Hazardous actions and attitudes
- Aggressive/abrupt control inputs
- Aircraft was operating at their maximum operating altitude. 41,000 feet. Entering the 410 club for a short time.
- They were at a full power setting, and nearing their stall speed.
- Region of reverse command.
- Once the engines lost power they quickly lost airspeed causing a stall, much like MCA.
- They were able to recover from this situation.
- Engines are made up of different metals, they have a specific heat value.
- They heat up and cool down at different rates.
- As we know, objects expand when heated and retract when cooled.
- The turbine binds up in the hot section, preventing it from spinning.
- The engine no longer has the airflow to compress the air. Because the aircraft was at such a high pitch angle, the engines did not have the required airflow to continue running.
- As a result, the engine stalls, or loses power.
- In this case, the aircraft had a dual engine flame-out, potentially caused by a compressor stall at high altitude.
- As we go higher in altitude, the air becomes less dense, making it more difficult to take in enough air to compress into the engine.
- High angles of attack meant that the engine airflow was interrupted, losing the pressure required for proper compression.
Accident Causes
- Misconduct of the flight crew
- Inadequate Airline Procedures
- Aircraft and Engine Manufacturers and certificating agencies