|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1801 To 2400|
|Locale Reference||atc facility : zdc.artcc|
|Altitude||msl single value : 24000|
|Controlling Facilities||artcc : zdc.artcc|
|Operator||common carrier : air carrier|
|Make Model Name||Regional Jet 200 ER&LR|
|Operating Under FAR Part||Part 121|
|Flight Phase||descent : approach|
|Route In Use||arrival star : n/s|
|Affiliation||company : air carrier|
|Function||flight crew : first officer|
|Experience||flight time last 90 days : 240|
flight time total : 4000
flight time type : 2000
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Experience||flight time total : 4500|
|Anomaly||aircraft equipment problem : less severe|
|Independent Detector||aircraft equipment other aircraft equipment : eicas|
other flight crewa
other flight crewb
|Resolutory Action||flight crew : landed as precaution|
flight crew : overcame equipment problem
Flight Crew Human Performance
Ahrs #2 failed. The failure was gradual over approximately 2 mins from notice of first indication of a problem. The first indications were unusual flight director variations and control wheel twitching. The flight director and heading/pitch indications deviated from our view of the actual horizon. At this point I disconnected the autoplt because the autoplt was chasing the bad ahrs data. The captain notified center and ran the QRH. As we continued to clt she contacted dispatch and maintenance as well as the flight attendant. This was a recurring problem in this aircraft. Maintenance in ZZZ; our point of departure; signed off on the repair. We were aware that this problem had occurred before and that maintenance had reported it fixed. I do not believe there were any significant deviations. The last 15 mins or so of the flight were hand flown. Any course; speed or altdevs; if there were any; probably would have occurred during the transition from automation to hand flying. Amber heading and att annunciations displayed on both pfd. Maximum display error was approximately 10 degrees pitch down in level flight. Supplemental information from acn 695582: on descent into clt; the first officer's flight director indicated a 5 degree nose down attitude. We received an EFIS comparator monitor caution message with a 'pit' on both pfd's. The ahrs #2 had been written up as failed on the previous flight; but had been reset by maintenance.
Original NASA ASRS Text
Title: CRJ200 FLT CREW HAS AHRS FAILURE; CONTINUES TO DEST AND LANDS.
Narrative: AHRS #2 FAILED. THE FAILURE WAS GRADUAL OVER APPROX 2 MINS FROM NOTICE OF FIRST INDICATION OF A PROB. THE FIRST INDICATIONS WERE UNUSUAL FLT DIRECTOR VARIATIONS AND CTL WHEEL TWITCHING. THE FLT DIRECTOR AND HDG/PITCH INDICATIONS DEVIATED FROM OUR VIEW OF THE ACTUAL HORIZON. AT THIS POINT I DISCONNECTED THE AUTOPLT BECAUSE THE AUTOPLT WAS CHASING THE BAD AHRS DATA. THE CAPT NOTIFIED CTR AND RAN THE QRH. AS WE CONTINUED TO CLT SHE CONTACTED DISPATCH AND MAINT AS WELL AS THE FLT ATTENDANT. THIS WAS A RECURRING PROB IN THIS ACFT. MAINT IN ZZZ; OUR POINT OF DEP; SIGNED OFF ON THE REPAIR. WE WERE AWARE THAT THIS PROB HAD OCCURRED BEFORE AND THAT MAINT HAD RPTED IT FIXED. I DO NOT BELIEVE THERE WERE ANY SIGNIFICANT DEVS. THE LAST 15 MINS OR SO OF THE FLT WERE HAND FLOWN. ANY COURSE; SPD OR ALTDEVS; IF THERE WERE ANY; PROBABLY WOULD HAVE OCCURRED DURING THE TRANSITION FROM AUTOMATION TO HAND FLYING. AMBER HDG AND ATT ANNUNCIATIONS DISPLAYED ON BOTH PFD. MAX DISPLAY ERROR WAS APPROX 10 DEGS PITCH DOWN IN LEVEL FLT. SUPPLEMENTAL INFO FROM ACN 695582: ON DSCNT INTO CLT; THE FO'S FLT DIRECTOR INDICATED A 5 DEG NOSE DOWN ATTITUDE. WE RECEIVED AN EFIS COMPARATOR MONITOR CAUTION MESSAGE WITH A 'PIT' ON BOTH PFD'S. THE AHRS #2 HAD BEEN WRITTEN UP AS FAILED ON THE PREVIOUS FLT; BUT HAD BEEN RESET BY MAINT.
Data retrieved from NASA's ASRS site as of January 2009 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.