 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Flight crew encountered static discharges that caused failure of flight instruments. Erratic indications from EFIS including right engine partial fire warning (no master warning) secured engine but did not blow fire bottles. EFIS (electrical flight instrument system).
| Attributes | |
| ACN | 198727 |
| Time | |
| Date | 199201 |
| Day | Wed |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : gij airport : fwa |
| State Reference | IN |
| Altitude | msl bound lower : 11000 msl bound upper : 11000 |
| Environment | |
| Flight Conditions | IMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : ptu |
| Operator | common carrier : air carrier |
| Make Model Name | Medium Transport, Low Wing, 2 Turboprop Eng |
| Flight Phase | cruise other descent : approach landing other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp pilot : cfi pilot : commercial pilot : instrument |
| Experience | flight time last 90 days : 180 flight time total : 10000 flight time type : 180 |
| ASRS Report | 198727 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : commercial pilot : atp pilot : instrument |
| Experience | flight time last 90 days : 240 flight time total : 13800 flight time type : 500 |
| ASRS Report | 198543 |
| Events | |
| Anomaly | aircraft equipment problem : critical inflight encounter : weather other anomaly other |
| Independent Detector | other flight crewa |
| Resolutory Action | flight crew : overcame equipment problem flight crew : declared emergency other |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Aircraft |
| Air Traffic Incident | other |
Narrative:
While level at 11000 ft MSL in IMC conditions with an OAT of plus 5 degree C several static discharges occurred on the windscreen. Within a couple of mins after the first discharge both captain's and first officer's primary flight displays and navigation displays went blank (EFIS). There were no indications on the central warning panel or master warning. After this occurrence aircraft attitude, altitude, airspeed and navigation were conducted by reference from the stand-by instruments located on the captain's control panel. The emergency checklist was complied with. Prior to departure destination airport WX was reported VFR and the radar was OTS. Lower altitudes to VFR were requested. Several mins after the EFIS failure the #2 communications radio beamed inoperative, due to static. At approximately 35 DME from destination airport at 5000 ft VFR conditions were maintained and the #2 communications radio was once again usable. At approximately 18 DME the right engine fire warning illuminated. We did not however receive a master warning or any central warning panel captions. All engine indicators and instruments were normal. The engine visually appeared not to be in any distress. The workload at this point was very heavy, due to the engine fire emergency, approach and landing checklists needed to be performed, while requesting the emergency equipment and advising the cabin crew. The emergency checklist was completed except for the discharge of fire bottles and clean up items. Due to the workload and the suspicion of a possible false fire warning. Landing was without any further incident. There was no aircraft damage or injury to passengers. Both flight crew members had knowledge of past false fire warnings due to faulty fire loops. The aircraft also has past history of torque fluctuations, power roll backs, automatic feathers and EFIS failures. The suspect cause was improper aircraft bonding, which has been resolved by proper maintenance.
Original NASA ASRS Text
Title: FLC ENCOUNTERED STATIC DISCHARGES THAT CAUSED FAILURE OF FLT INSTS. ERRATIC INDICATIONS FROM EFIS INCLUDING R ENG PARTIAL FIRE WARNING (NO MASTER WARNING) SECURED ENG BUT DID NOT BLOW FIRE BOTTLES. EFIS (ELECTRICAL FLT INST SYS).
Narrative: WHILE LEVEL AT 11000 FT MSL IN IMC CONDITIONS WITH AN OAT OF PLUS 5 DEG C SEVERAL STATIC DISCHARGES OCCURRED ON THE WINDSCREEN. WITHIN A COUPLE OF MINS AFTER THE FIRST DISCHARGE BOTH CAPT'S AND FO'S PRIMARY FLT DISPLAYS AND NAV DISPLAYS WENT BLANK (EFIS). THERE WERE NO INDICATIONS ON THE CENTRAL WARNING PANEL OR MASTER WARNING. AFTER THIS OCCURRENCE ACFT ATTITUDE, ALT, AIRSPD AND NAV WERE CONDUCTED BY REF FROM THE STAND-BY INSTS LOCATED ON THE CAPT'S CTL PANEL. THE EMER CHKLIST WAS COMPLIED WITH. PRIOR TO DEP DEST ARPT WX WAS RPTED VFR AND THE RADAR WAS OTS. LOWER ALTS TO VFR WERE REQUESTED. SEVERAL MINS AFTER THE EFIS FAILURE THE #2 COMS RADIO BEAMED INOP, DUE TO STATIC. AT APPROX 35 DME FROM DEST ARPT AT 5000 FT VFR CONDITIONS WERE MAINTAINED AND THE #2 COMS RADIO WAS ONCE AGAIN USABLE. AT APPROX 18 DME THE R ENG FIRE WARNING ILLUMINATED. WE DID NOT HOWEVER RECEIVE A MASTER WARNING OR ANY CENTRAL WARNING PANEL CAPTIONS. ALL ENG INDICATORS AND INSTS WERE NORMAL. THE ENG VISUALLY APPEARED NOT TO BE IN ANY DISTRESS. THE WORKLOAD AT THIS POINT WAS VERY HVY, DUE TO THE ENG FIRE EMER, APCH AND LNDG CHKLISTS NEEDED TO BE PERFORMED, WHILE REQUESTING THE EMER EQUIP AND ADVISING THE CABIN CREW. THE EMER CHKLIST WAS COMPLETED EXCEPT FOR THE DISCHARGE OF FIRE BOTTLES AND CLEAN UP ITEMS. DUE TO THE WORKLOAD AND THE SUSPICION OF A POSSIBLE FALSE FIRE WARNING. LNDG WAS WITHOUT ANY FURTHER INCIDENT. THERE WAS NO ACFT DAMAGE OR INJURY TO PAXS. BOTH FLC MEMBERS HAD KNOWLEDGE OF PAST FALSE FIRE WARNINGS DUE TO FAULTY FIRE LOOPS. THE ACFT ALSO HAS PAST HISTORY OF TORQUE FLUCTUATIONS, PWR ROLL BACKS, AUTO FEATHERS AND EFIS FAILURES. THE SUSPECT CAUSE WAS IMPROPER ACFT BONDING, WHICH HAS BEEN RESOLVED BY PROPER MAINT.
Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.