# Incident 19980222003769I: Saab 340B, Lawton, OK, February 22, 1998 - Type: FAA incident report (Accident/Incident Data System), as reported - Date: February 22, 1998, 10:21 local time - Place: Lawton, OK - Airport: Lawton Municipal - Damage: Minor damage - Phase of flight: Level Off Touchdown - Operating rules: Air carrier (Part 121) - Operator: SIMA - Location: 34.5590° N, 98.2901° W: From the FAA, an estimate near the named town, within about 3 miles - Nearby events: https://openairdocs.org/map.md?lat=34.5590&lon=-98.2901&mi=10 - Aircraft: N396AE, a cancelled registration (https://openairdocs.org/deregistered/N396AE-2009-10-19) (OpenAirDocs) - Registry model: Saab-Scania SAAB 340B (registry code 7860101, https://openairdocs.org/model/saab-scania-saab-340b) (OpenAirDocs) - Registry engine: GE CT7-SER series (registry code 30031, https://openairdocs.org/engine/ge-ct7-ser-series) (OpenAirDocs) - Reported make and model: SAAB 340B - Reported engine: GE CT79B - People aboard: 6 - Fatal injuries: 0 - Pilot flight hours: 7,993 total, 2,341 in this make and model, 343 in the last 90 days - NTSB investigation: [NTSB FTW98IA130](https://openairdocs.org/ntsb/FTW98IA130) (OpenAirDocs) - FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/) - Page: https://openairdocs.org/incident/19980222003769I ## Narrative As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^. NARRATIVE: ON FEBRUARY 22, 1998, AT 1021 CENTRAL STANDARD TIME, A SAAB 340B TRANSPORT AIRPLANE, N396AE, OPERATED BY SIMMONS AIRLINES, INC., AS AMERICAN EAGLE FLIGHT 509, EXPERIENCED A COLLAPSED LEFT MAIN LANDING GEAR WHILE LANDING AT THE LAWTON-FORT SILL REGIONAL AIRPORT, NEAR LAWTON, OKLAHOMA. THE FLIGHT WHICH ORIGINATED AT THE DFW INTERNATIONAL AIRPORT AT APPROXIMATELY 0941, WAS BEING OPERATED UNDER TITLE 14 CFR PART 121. THE AIRPLANE SUSTAINED MINOR DAMAGE AND THERE WERE NO INJURIES TO THE 3 PASSENGERS AND 3 CREWMEMBERS ABOARD THE AIRPLANE. VISUAL METEOROLOGICAL CONDITIONS PREVAILED AND AN IFR FLIGHT PLAN WAS FILED FOR THE SCHEDULED FLIGHT. ACCORDING TO PRELIMINARY INFORMATION PROVIDED BY THE OPERATOR, THE FLIGHT CREW REPORTED THAT WHILE EN ROUTE TO LAWTON, THEY SMELLED THE ODOR OF ELECTRICAL HEAT AND DISCOVERED THAT THE GEAR CONTROL CIRCUIT BREAKER HAD POPPED. THE FLIGHT CREW NOTIFIED THEIR COMPANY'S MAINTENANCE OPERATIONS CENTER BY RADIO AND AFTER DISCUSSING ALL THEIR OPTIONS, ELECTED TO CONTINUE ON TO LAWTON, WHICH IS ONE OF THE COMPANY'S MAINTENANCE BASES. AFTER RESETTING THE POPPED CIRCUIT BREAKER, THE LANDING GEAR SELECTOR WAS PLACED IN THE DOWN POSITION AND THE CREW RECEIVED INDICATIONS THAT THE NOSE LANDING GEAR WAS "DOWN AND LOCKED" AND THE TWO MAIN GEARS WERE UNSAFE. THE FLIGHT CREW INITIATED EMERGENCY PROCEDURES TO EXTEND THE HYDRAULICALLY OPERATED LANDING GEAR BY ALTERNATE MEANS. THE CREW ELECTED TO EXECUTE THREE TOWER FLY-BYS TO VERIFY THE POSITION OF THE TWO MAIN LANDING GEARS, WHICH VISUALLY APPEARED TO BE DOWN AND LOCKED FROM THE CABIN; HOWEVER, WERE INDICATING TO BE "UNSAFE" IN THE COCKPIT. AFTER THE THIRD TOWER FLY-BY, THE AIRPLANE WAS CLEARED TO LAND ON RUNWAY 35 WITH EMERGENCY EQUIPMENT STANDING BY. WITNESSES AT THE AIRPORT REPORTED THAT THE LEFT MAIN LANDING GEAR COLLAPSED AS SOON AS WEIGHT WAS PLACED ON THE LANDING GEAR SOON AFTER TOUCHDOWN. THE AIRPLANE SLID OFF THE RUNWAY AND CAME TO REST IN A MUDDY AREA APPROXIMATELY 2,500 FEET FROM THE TOUCH DOWN POINT, ABOUT 75 FEET WEST OF THE RUNWAY. ALL OCCUPANTS EXITED THE AIRPLANE SAFELY THROUGH THE LEFT OVER WING EXIT. NO FIRE WAS REPORTED. EXAMINATION OF THE AIRPLANE BY THE FAA INSPECTOR CONFIRMED DAMAGE TO THE LEFT FLAP, COWLING, LANDING GEAR DOORS AND PROPELLER. (-23)A SAAB 340B (N396AE) EXPERIENCED A GEAR MOTOR MALFUNCATION IN FLIGHT R ESULTING IN AN UNSAFE GEAR INDICATION. AFTER APPRORIATE EMERGENCY PROCEDURES WERE COMPLETED THE AIRCRAFT LANDED AND THE LEFT MAIN GEAR COLLAPSED. THE AIRCRAFT SLID OFF THE RUNWAY APPROXIMATELY 2500 FEET FROM TOUCHDOWN. THE CREW AND PASSENGERS EXITED SAFELY. (.4)DURING CRUISE FLIGHT, THE FLIGHT CREW REPORTED SMELLING AN ODOR SIMILAR TO BURNING/SMOLDERING ELECTRICAL EQUIPMENT AND NOTICED THAT THE LANDING GEAR CONTROL CIRCUIT BREAKER HAD POPPED. THE FLIGHT CREW CONSULTED THE COMPANY'S QUICK REFERENCE HANDBOOK (QRH). THE QRH ADDRESSED HYDRAULIC PROBLEMS AND FAILED TO DISCUSS POSSIBLE ELECTRICAL PROBLEMS RELATED TO THE OPERATION OF THE LANDING GEAR. THE COMPANY'S MAINTENANCE FACILITY WAS APPRAISED OF THE SITUATION; HOWEVER, THE MAINTENANCE PERSON ON DUTY WAS NOT ABLE TO ASSIST THE FLIGHT CREW. THREE TOWER FLY-BYS WERE MADE. THE FLIGHT ATTENDANT AND TOWER PERSONNEL REPORTED THAT THE LANDING GEAR APPEARED TO BE DOWN AND THE GEAR DOORS WERE CLOSED. THE FLIGHT CREW ELECTED TO LAND WITH THE LIGHT ON THE GEAR HANDLE INDICATING AN 'IN-TRANSIT' CONDITION AND THE TWO MAIN LANDING GEAR INDICATORS IN THE 'UNSAFE' CONDITION. THE LEFT MAIN LANDING GEAR ON TH E TWIN-ENGINE TRANSPORT CATEGORY AIRPLANE COLLAPSED DURING THE LANDING ROLL. EXAMINATION REVEALED THAT THE WEIGHT-ON-WHEELS RELAY, WHICH IS LOCATED IN THE AVIONICS BAY DIRECTLY UNDER THE CAPTAIN'S STATION, SHORTED, AND AS A RESULT, THE LANDING GEAR CONTROL CIRCUIT BREAKER POPPED. THE ELECTRICAL SHORT WAS ATTRIBUTED TO THE SPILL OF A SODA CAN ON THE FLIGHT DECK ON A PREVIOUS FLIGHT. THE INVESTIGATION REVEALED THAT THE COCKPIT FLOOR WAS NOT CARPETED OR SEALED TO PREVENT FLUIDS/MOISTURE FROM SEEPING INTO THE ELECTRICAL COMPARTMENT BENEATH THE COCKPIT FLOOR. A REVIEW OF THE EMERGENCY EXTENSION SYSTEM FOR THE AIRPLANE REVEALED THAT THE LANDING GEAR COULD HAVE BEEN EXTENDED IF THE FIGHT CREW HAD PULLED THE EMERGENCY EXTENSION HANDLE. ## 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 FTW98IA130](https://openairdocs.org/ntsb/FTW98IA130), Feb 22, 1998: Saab-Scania 340B (N396AE), Lawton, OK, incident, minor damage. Probable cause: the collapse of the left main landing gear during landing roll as result of a shorted weight-on-wheels relay. Contributing factors were the insufficient information available to the flight crew in… ## Other reports on N396AE (1) Matched to the same aircraft by N-number and date. - [Incident 20000523033449I](https://openairdocs.org/incident/20000523033449I), May 23, 2000: Saab 340B (N396AE), Lafayette, LA, Minor damage. (-23)American eagle flight 393, N396AE, while taxing to parking, struck the right wing of parked N202KD, also operated by American eagle. The right aleron of… 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.