# Incident 19951228045239I: Swrngn SA227AC, Bemidji, MN, December 28, 1995 - Type: FAA incident report (Accident/Incident Data System), as reported - Date: December 28, 1995, 17:45 local time - Place: Bemidji, MN - Airport: Bemidji-Beltrami County - Phase of flight: Fcd/Prec Ldg From Cruise - Operating rules: Air taxi and commuter (Part 135) - Operator: MALA - Location: 47.4800° N, 94.8696° W: From the FAA, an estimate near the named town, within about 3 miles - Nearby events: https://openairdocs.org/map.md?lat=47.4800&lon=-94.8696&mi=10 - Aircraft: N159MC, registered now (https://openairdocs.org/aircraft/N159MC) (OpenAirDocs) - Registry model: Fairchild SA227-AC (registry code 3377509, https://openairdocs.org/model/fairchild-sa227-ac) (OpenAirDocs) - Registry engine: AiResearch TPE331 series (registry code 01514, https://openairdocs.org/engine/airesearch-tpe331-series) (OpenAirDocs) - Reported make and model: SWRNGN SA227AC - Reported engine: GARRTT TPE33111U - People aboard: 16 - Fatal injuries: 0 - Pilot flight hours: 5,600 total, 3,400 in this make and model, 116 in the last 90 days - NTSB investigation: [NTSB CHI96IA066](https://openairdocs.org/ntsb/CHI96IA066) (OpenAirDocs) - FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/) - Page: https://openairdocs.org/incident/19951228045239I ## Narrative As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^. NARRATIVE: ON DECEMBER 26, 1995 MESABA RECORDS SHOW EXTENSIVE MAINTENANCE ON FAIRCHILD SA-227 AIRCRAFT N159MC IN THE AREA OF THE ELEVATOR QUADRANT. DURING THE MAINTENANCE, A MECHANIC FOLLOWING MAINTENANCE MANUAL PROCEDURES, REMOVED THE UPPER ELEVATOR BOLT AND RELATED HARDWARE. WITH THE QUADRANT REMOVED AND ON A BENCH, ANOTHER MECHANIC LOOSELY INSTALLED THE HARDWARE BACK ON THE QUADRANT, SO THE HARDWARE WOULD NOT BE LOST. "LOOSELY INSTALLED" AS USED HERE MEANS, THE ELEVATOR BOLT AND RELATED HARDWARE WERE INSTALLED, WITH THE SELF LOCKING NUT TIGHTENED MANUALLY ONLY, IT WAS NOT PROPERLY TORQUED. THE SELF LOCKING FEATURE OF THE NUT WAS DETERIORATED. THE NUT PRESENTED TO FAA BY MESABA, AS THE NUT REMOVED FROM N159MC COULD BE RUN DOWN ON THE BOLT TO THE POINT WHERE ONE THREAD EXTENDED BEYOND THE NUT. THIS POSITION OF THE NUT, WITH THE DETERIORATED LOCKING FEATURE, HAND TIGHTENED ON THE BOLT, I.E. ONE THREAD SHOWING PAST THE NUT, IS CLOSE TO THE APPEARANCE OF A NUT INSTALLED WITH THE PROPER TORQUE. IN CONTRAST, A NEW NUT COULD ONLY BE RUN DOWN A FEW TURNS ON THE BOLT. SUBSEQUENTLY, MECHANICS INSTALLED THE QUADRANT, WITH THE IMPROPERLY INSTALLED STOP BOLT ON THE AIRCRAFT. AN INSPECTOR, PO SSIBLY BECAUSE THE NUT APPEARED TORQUED, DID NOT NOTICE THE IMPROPER INSTALLATION. THE ELEVATOR QUADRANT COULD NOT BE REMOVED IN THE MANNER SPECIFIED BY MAINTENANCE MANUAL PROCEDURES. THE PROCEDURES CALLED FOR THE UPPER ELEVATOR STOP (BOLT, NUT , ECCENTRIC) TO BE REMOVED, WITH THE QUADRANT TO BE ROTATED DOWN THROUGH THE CASTING STOP AND THEN REMOVED FROM THE AIRCRAFT. THICKNESS OF THE QUADRANT MATERIAL AT THE ELEVATOR STOP BOLT HOLES PREVENTED ROTATION OF THE ELEVATOR QUADRANT THROUGH THE NARROWER STOP CASTING. THEREFORE, OPERATOR PERSONNEL REMOVED THE STOP CASTING BEFORE REMOVING THE QUADRANT. IN REMOVING THE QUADRANT BY FIRST REMOVING THE STOP CASTING, ITS NOT NECESSARY TO REMOVE THE UPPER ELEVATOR STOP HARDWARE. SOME OPERATOR PERSONNEL WERE AWARE OF THIS, OTHERS WERE NOT. ON DECEMBER 28, 1995, 16 FLIGHTS AFTER THE ABOVE MAINTENANCE, ON THE APPROACH OF FLIGHT 3237 (MSP) (MINNEAPOLIS)-BJI (BEMIDJI, MN) INTO BJI, THE CREW REPORTED THE AIRCRAFT PITCHED DOWN EXCESSIVELY AND THE ELEVATOR COULD NOT BE MOVED TO FULL UP BY THE CONTROL COLUMN. SUBSEQUENTLY THE CREW INITIATED A GO-AROUND AND USED POWER TO CONTROL PITCH FOR LANDING. EXCESSIVE DESCENT RATE AND AIRSPEED AT LANDING RESULTED INHEAVY LANDING. MAINTENANCE INVESTIGATION FOUND A WORKED OUT UPPER ELEVATOR STOP BOLT IN THE ELEVATOR QUADRANT PREVENTED ELEVATOR MOVEMENT FROM ABOUT NEUTRAL TO FULL UP. THE BOLT WORKED OUT ABOUT 2". UPON MOVEMENT OF THE CONTROL COLUMN FOR UP, THE WORKED OUT BOLT, MOVING UPWARD WITH THE ELEVATOR CONTROL QUADRANT CONTACTED THE UNDERSIDE OF A STRINGER (THE FIRST STRINGER JUST ABOVE THE RELATED ACCESS PANEL ON THE RIGHT SIDE OF THE VERTICAL STABILIZER). THIS CONTACT PREVENTED FURTHER MOVEMENT OF THE ELEVATOR IN THE UP DIRECTION. THE BOLT APPEARS TO BE BENT FROM THIS CONTACT AND FORCE EXERTED BY THE CREW WHEN PULLING THE CONTROL COLUMN BACK. MESABA COMPLETED A FLEET CAMPAIGN TO CHECK UPPER AND LOWER ELEVATOR STOP BOLTS AND TO REPLACE THE SELF LOCKING NUTS.THEY ARE WORKING WITH FAIRCHILD TO CORRECT THE MAINTENANCE MANUAL, AND ARE INITIATING AND/OR EVALUATING OTHER CORRECTIVE ACTIONS. ## The NTSB's investigation of this event (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB CHI96IA066](https://openairdocs.org/ntsb/CHI96IA066), Dec 28, 1995: Fairchild SA227-AC (N159MC), Bemidji, MN, incident, no damage. Probable cause: inadequate maintenance installation and inspection of the elevator flight control system which led to restricted flight control elevator movement due to a loose bolt. ## Other reports on N159MC (5) Matched to the same aircraft by N-number and date. - [Incident 20040303002999I](https://openairdocs.org/incident/20040303002999I), Mar 3, 2004: Swrngn SA227AC (N159MC), Spokane, WA. (-23) Big sky flight 1410, Spokane (geg), Washington, to olympia, Washington, declared emergency and returned to geg with gear warning light. Aircraft landed… - [Incident 19991026030149I](https://openairdocs.org/incident/19991026030149I), Oct 26, 1999: Swrngn SA227AC (N159MC), Billings, MT. (-23) On 10/26/99 at 0719 LCL MDT, a big sky airlines fairchild SA-227-AC, N159MC, experienced a hydraulic failure of the landing gear system. During landing,… - [Incident 19981022033669I](https://openairdocs.org/incident/19981022033669I), Oct 22, 1998: Swrngn SA227AC (N159MC), Billings, MT. On 10/22/98 @ 1900 mlcl aircraft N159MC left engine failed to generate required engine torque during take-off roll. The crew aborted take-off and returned to… - [Incident 19970326008319I](https://openairdocs.org/incident/19970326008319I), Mar 26, 1997: Swrngn SA227AC (N159MC), Omaha, NE. Narrative: N159MC, a SA-227-AC being operated as mesaba airlines flight 3049, departed lincoln, Nebraska, enroute to minneapolis, Minnesota, on March 26, 1997.… - [Accident 19910928063109A](https://openairdocs.org/incident/19910928063109A), Sep 28, 1991: Swrngn SA227AC (N159MC), Atlantic City, NJ, Substantial damage. Right main gear collapsed on touchdown. Right prop wing tip hit runway. Down lock bearing failed. From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.