On October 14, 2004, about 2215:06 central daylight time, Pinnacle Airlines flight 3701 (doing business as Northwest Airlink), a Bombardier CL-600-2B19, N8396A, crashed into a residential area about 2.5 miles south of Jefferson City Memorial Airport, Jefferson City, Missouri. The airplane was on a repositioning flight from Little Rock National Airport, Little Rock, Arkansas, to Minneapolis-St. Paul International Airport, Minneapolis, Minnesota. During the flight, both engines flamed out after a pilot-induced aerodynamic stall and were unable to be restarted. The captain and the first officer were killed, and the airplane was destroyed. No one on the ground was injured. The flight was operating under the provisions of 14 Code of Federal Regulations Part 91 on an instrument flight rules flight plan. Visual meteorological conditions prevailed at the time of the accident.
The National Transportation Safety Board determines that the probable causes of this accident were (1) the pilots' unprofessional behavior, deviation from standard operating procedures, and poor airmanship, which resulted in an in-flight emergency from which they were unable to recover, in part because of the pilots' inadequate training; (2) the pilots' failure to prepare for an emergency landing in a timely manner, including communicating with air traffic controllers immediately after the emergency about the loss of both engines and the availability of landing sites; and (3) the pilots' improper management of the double engine failure checklist, which allowed the engine cores to stop rotating and resulted in the core lock engine condition. Contributing to this accident were (1) the core lock engine condition, which prevented at least one engine from being restarted, and (2) the airplane flight manuals that did not communicate to pilots the importance of maintaining a minimum airspeed to keep the engine cores rotating.
The safety issues discussed in this report focus on flight crew training in the areas of high altitude climbs, stall recognition and recovery, and double engine failures; flight crew professionalism; and the quality of some parameters recorded by flight data recorders on regional jet airplanes. Safety recommendations concerning these issues are addressed to the Federal Aviation Administration.
As a result of the investigation of this accident, the National Transportation Safety Board makes the following recommendations to the Federal Aviation Administration:
Work with members of the aviation industry to enhance the training syllabuses for pilots conducting high altitude operations in regional jet airplanes. The syllabuses should include methods to ensure that these pilots possess a thorough understanding of the airplanes' performance capabilities, limitations, and high altitude aerodynamics. (A-07-1)
Determine whether the changes to be made to the high altitude training syllabuses for regional jet airplanes, as requested in Safety Recommendation A-07-1, would also enhance the high altitude training syllabuses for all other transport-category jet airplanes and, if so, require that these changes be incorporated into the syllabuses for those airplanes. (A-07-2)
Require that air carriers provide their pilots with opportunities to practice high altitude stall recovery techniques in the simulator during which time the pilots demonstrate their ability to identify and execute the appropriate recovery technique. (A-07-3)
Convene a multidisciplinary panel of operational, training, and human factors specialists to study and submit a report on methods to improve flight crew familiarity with and response to stickpusher systems and, if warranted, establish training requirements for stickpusher-equipped airplanes based on the findings of this panel. (A-07-4)
Verify that all Canadair regional jet operators incorporate guidance in their double engine failure checklist that clearly states the airspeeds required during the procedure and require the operators to provide pilots with simulator training on executing this checklist. (A-07-5)
Require regional air carriers operating under 14 Code of Federal Regulations Part 121 to provide specific guidance on expectations for professional conduct to pilots who operate nonrevenue flights. (A-07-6)
For those regional air carriers operating under 14 Code of Federal Regulations Part 121 that have the capability to review flight data recorder (FDR) data, require that the air carriers review FDR data from nonrevenue flights to verify that the flights are being conducted according to standard operating procedures. (A-07-7)
Work with pilot associations to develop a specific program of education for air carrier pilots that addresses professional standards and their role in ensuring safety of flight. The program should include associated guidance information and references to recent accidents involving pilots acting unprofessionally or not following standard operating procedures. (A-07-8)
Require that all 14 Code of Federal Regulations Part 121 operators incorporate into their oversight programs periodic Line Operations Safety Audit observations and methods to address and correct findings resulting from these observations. (A-07-9)
Require that all 14 Code of Federal Regulations Part 121 operators establish Safety Management System programs. (A-07-10)
Strongly encourage and assist all regional air carriers operating under 14 Code of Federal Regulations Part 121 to implement an approved Aviation Safety Action Program and an approved Flight Operational Quality Assurance program. (A-07-11)
Previously Issued Recommendation Reiterated and Classified in This Report
The Safety Board reiterates the following recommendation to the Federal Aviation Administration:
Require that all Embraer 145, Embraer 135, Canadair CL-600 RJ, Canadair Challenger CL-600, and Fairchild Dornier 328-300 airplanes be modified with a digital flight data recorder system that meets the sampling rate, range, and accuracy requirements specified in 14 Code of Federal Regulations Part 121.344, Appendix M. (A-03-15)
Further, Safety Recommendation A-03-15 (previously classified "Open-Acceptable Response") is classified "Open-Unacceptable Response" in section 2.5 of this report.
For information about this recommendation, see sections 126.96.36.199 and 2.5 of this report.
Previously Issued Recommendations Resulting From This Accident Investigation
As a result of the investigation into this accident, the Safety Board issued the following recommendations to the Federal Aviation Administration on November 20, 2006:
For airplanes equipped with CF34-1 or CF34-3 engines, require manufacturers to perform high power, high altitude sudden engine shutdowns; determine the minimum airspeed required to maintain sufficient core rotation; and demonstrate that all methods of in-flight restart can be accomplished when this airspeed is maintained. (A-06-70)
Ensure that airplane flight manuals of airplanes equipped with CF34-1 or CF34-3 engines clearly state the minimum airspeed required for engine core rotation and that, if this airspeed is not maintained after a high power, high altitude sudden engine shutdown, a loss of in-flight restart capability as a result of core lock may occur. (A-06-71)
Require that operators of CRJ-100, -200, and -440 airplanes include in airplane flight manuals the significant performance penalties, such as loss of glide distance and increased descent rate, that can be incurred from maintaining the minimum airspeed required for core rotation and windmill restart attempts. (A-06-72)
Review the design of turbine-powered engines (other than the CF34-1 and CF34-3, which are addressed in Safety Recommendation A-06-70) to determine whether they are susceptible to core lock and, for those engines so identified, require manufacturers of airplanes equipped with these engines to perform high power, high altitude sudden engine shutdowns and determine the minimum airspeed to maintain sufficient core rotation so that all methods of in-flight restart can be accomplished. (A-06-73)
For those airplanes with engines that are found to be susceptible to core lock (other than the CF34-1 and CF34-3, which are addressed in Safety Recommendation A-06-71), require airplane manufacturers to incorporate information into airplane flight manuals that clearly states the potential for core lock; the procedures, including the minimum airspeed required, to prevent this condition from occurring after a sudden engine shutdown; and the resulting loss of in-flight restart capability if this condition were to occur. (A-06-74)
Require manufacturers to determine, as part of 14 Code of Federal Regulations Part 25 certification tests, if restart capability exists from a core rotation speed of 0 indicated rpm after high power, high altitude sudden engine shutdowns. For those airplanes determined to be susceptible to core lock, mitigate the hazard by providing design or operational means to ensure restart capability. (A-06-75)
Establish certification requirements that would place upper limits on the value of the minimum airspeed required and the amount of altitude loss permitted for windmill restarts. (A-06-76)
For additional information about these recommendations, see section 188.8.131.52 of this report.