Narrative:DC-8 N827AX had received major modifications at Triad International Maintenance Corporation (TIMCO), including a "D" check (major airplane overhaul), modification and standardization of cockpit, avionics and airplane systems, installation of a cargo handling system and engine modifications to achieve Stage III noise level requirements. A partial functional evaluation flight was conducted on December 21, 1996, but was terminated when the airplane developed a hydraulic system anomaly (low fluid quantity indication). Due to maintenance delays the aircraft departed 4 hours and 20 minutes late, at 17:40, the following day. The crew were assigned a block altitude of FL130 to FL150 with an IFR clearance back to Greensboro Airport. The planned flight duration was about 2 hours. The airplane climbed through FL90feet at 17:43 and was level at FL141 at 17:45. At 18:05, after performing several landing gear, hydraulic and engine system checks, the flight engineer told the other flight crew members that the "next thing is our stall series. The evaluation flight profile form required that the flight crew identify and record the speed at which the stick shaker activated and the speed of the stall indication. The crew slowed the aircraft down one knot at a time. At 18:08:09, the sound of rattling was heard on the CVR and, at 18:08:11, the flight engineer said "thats a stall right there... aint no [stick] shaker" (at 145 knots). The crew tried to recover from the stall by selecting maximum power. The nose was brought down to gain speed. Not able to recover from the stall, the aircraft struck mountainous terrain in a 52-degree, left wing low and 26-degree, nose-down attitude about 3,400 feet msl.
Probable Cause:
PROBABLE CAUSE: " The National Transportation Safety Board determines that the probable causes of this accident were the inappropriate control inputs applied by the flying pilot during a stall recovery attempt, the failure of the non-flying pilot-in-command to recognize, address and correct these inappropriate control inputs, and the failure of Airborne Express to establish a formal, functional evaluation flight program that included adequate program guidelines, requirements and pilot training for performance of these flights.
Contributing to the cause of the accident were the inoperative stick shaker stall warning system and Airborne Express DC-8 flight training simulator's inadequate fidelity in reproducing the airplane's stall characteristics."
Accident investigation:
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Investigating agency: | NTSB  |
Status: | Investigation completed |
Duration: | 205 days (7 months) | Accident number: | NTSB/AAR-97-05 | Download report: | Final report
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Classification:
Loss of control
Sources:
»
SKYbrary » Aviation Week & Space Technology 3.3.1997 (41)
» Business & Commercial Aviation Nov. 1997 (98)
» NTSB/AAR-97/05
»
After Intentionally Stalling DC-8, Crew Uses Incorrect Recovery Technique, Resulting in Uncontrolled Descent and Collision with Terrain
Follow-up / safety actions
NTSB issued 7 Safety Recommendations
Issued: 29-JUL-1997 | To: FAA | A-97-46 |
REQUIRED DOUGLAS AIRCRAFT COMPANY TO REVIEW & AMEND THE STALL WARNING TEST PROCEDURES IN THE DC-8 MAINTENANCE PLANNING DOCUMENT TO INCLUDE REGULAR CALIBRATION & FUNCTIONAL CHECKS OF THE COMPLETE STALL WARNING SYSTEM. (Closed - Acceptable Action) |
Issued: 29-JUL-1997 | To: FAA | A-97-47 |
EVALUATE THE DATA AVAILABLE ON THE STALL CHARACTERISTICS OF AIPLANES USED IN AIR CARRIER SERVICE &, IF APPROPRIATE, REQUIRE THE MANUFACTURERS & OPERATORS OF FLIGHT SIMULATORS USED IN AIR CARRIER PILOT TRAINING TO IMPROVE THE FIDELITY OF THESE SIMULATORS IN REPRODUCING THE STALL CHARACTERISTICS OF THE AIRPLANES THEY REPRESENT TO THE MAXIMUM EXTENT THAT IS PRACTICAL; THEN ADD TRAINING IN RECOVERY FROM STALLS WITH PITCH ATTITUDES AT OR BELOW THE HORIZON TO THE SPECIAL EVENTS TRAINING PROGRAMS OF AIR CARRIERS. (Closed - Unacceptable Action) |
Issued: 29-JUL-1997 | To: FAA | A-97-48 |
ENSURE THAT ABX EXPLICITLY INCORPORATES THE REVISED FUNCTIONAL EVALUATION FLIGHT STALL RECOVERY PROCEDURE (THAT WAS AGREED UPON IN 1991 BY ABX & THE FAA), OR AN EQUIVALENT PROCEDURE, IN ITS DC-8 FUNCTIONAL EVALUATION FLIGHT PROGRAM. (Closed - Acceptable Action) |
Issued: 29-JUL-1997 | To: FAA | A-97-49 |
DEVELOP AN ADVISORY CIRCULAR THAT PROVIDES GUIDANCE TO AIR CARRIERS ON THE APPROPRIATE CONDITIONS, LIMITATIONS & TOLERANCES FOR THE PERFORMANCE OF FUNCTIONAL EVALUATION FLIGHTS & THE SPECIFIC MANEUVERS PERFORMED DURING THESE FLIGHTS, INCLUDING APPROACH TO STALLS. (Closed - Acceptable Alternate Action) |
Issued: 29-JUL-1997 | To: FAA | A-97-50 |
IDENTIFY THE SET OF OPERATIONS CONDUCTED BY AIR CARRIERS THAT REQUIRE SPECIAL CONSIDERATION, INCLUDING FUNCTIONAL EVALUATION FLIGHTS & OTHER NONROUTINE OPERATIONS THAT HAVE SIMILAR NEEDS FOR TRAINING & OPERATIONAL GUIDANCE; THEN AMEND AIR CARRIER OPERATIONS SPECIFICATIONS TO INCLUDE APPROPRIATE GUIDELINES & LIMITATIONS FOR THESE NONROUTINE OPERATIONS & AMEND SUBPART N OF TITLE 14 CODE OF FEDERAL REGULATION PART 121 TO REQUIRE AIR CARRIERS TO ESTABLISH APPROPRIATE FLIGHTCREW TRAINING & QUALIFICATION REQUIREMENTS IN THEIR TRAINING MANUALS. (Closed - Acceptable Alternate Action) |
Issued: 29-JUL-1997 | To: FAA | A-97-51 |
UNDERTAKE AN APPROPRIATE LEVEL OF SURVEILLANCE OF THE FUNCTIONAL EVALUATION FLIGHT PROGRAMS OF ALL AIR CARRIERS, FOLLOWING IMPLEMENTATION OF THE BOARD\'S SUGGESTED CHANGES TO FUNCTIONAL EVALUATION FLIGHT & OTHER NONROUTINE OPERATIONS. (Closed - Acceptable Action) |
Issued: 29-JUL-1997 | To: FAA | A-97-52 |
MODIFY THE OPERATING & AIRWORTHINESS REGULATIONS OF TITLE 14 CODE OF FEDERAL REGULATIONS OR ISSUE APPROPRIATE GUIDANCE MATERIAL TO CLARIFY AIRWORTHINESS & OPERATIONAL PROCEDURAL REQUIREMENTS FOR CONDUCTING FUNCTIONAL FLIGHTS IN TRANSPORT-CATEGORY AIRCRAFT. (Closed - Acceptable Action) |
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accident date:
22-12-1996type: McDonnell Douglas DC-8-63F
registration: N929R
Map
This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.