|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Locale Reference||airport : mdw.airport|
|Altitude||msl single value : 38000|
|Controlling Facilities||artcc : zau.artcc|
|Operator||common carrier : air carrier|
|Make Model Name||B737-700|
|Operating Under FAR Part||Part 121|
|Flight Phase||cruise : level|
|Affiliation||company : air carrier|
|Function||flight crew : first officer|
|Experience||flight time last 90 days : 177|
flight time type : 177
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Experience||flight time last 90 days : 219|
|Anomaly||aircraft equipment problem : less severe|
non adherence : far
non adherence : published procedure
|Independent Detector||other flight crewa|
other flight crewb
|Resolutory Action||none taken : detected after the fact|
|Problem Areas||Flight Crew Human Performance|
|Primary Problem||Flight Crew Human Performance|
We departed normally from mdw. I was the first officer and the PNF. When the PF attempted to engage the autopilot; the a system would only stay engage for 5 seconds and then disengage on its own. The B system would not engage at all. We troubleshot the problem during our en route climb and determined that we could not fix either autopilot. We flew to our destination uneventfully without the autopilot. No altitude deviations occurred and no requests to call ATC were received. We traded aircraft control once during flight to allow the captain to recharge prior to our approach. We landed without incident and had the autopilot fixed. It occurred to me later that day that we should not have flown in rvsm airspace. The fom tab on rvsm and the MEL are quite clear on the subject. Our error was not informing ATC that we needed 2000 ft of separation. We were both attentive to maintaining altitude and neither one of us thought to refer to the MEL or the fom. We did refer to the QRH but did not find any relevant information. I as the PNF probably should have had the situational awareness to check the fom and opc. Given that dual autopilot failures are not a common occurrence; perhaps a QRH page that repeats the rvsm implications would have been helpful.
Original NASA ASRS Text
Title: IT APPEARS THE FLT CREW LOST BOTH AUTOPLTS AND DID NOT NOTIFY ATC OF THE EQUIP LOSS WHILE IN RVSM AIRSPACE.
Narrative: WE DEPARTED NORMALLY FROM MDW. I WAS THE FO AND THE PNF. WHEN THE PF ATTEMPTED TO ENGAGE THE AUTOPILOT; THE A SYSTEM WOULD ONLY STAY ENGAGE FOR 5 SECONDS AND THEN DISENGAGE ON ITS OWN. THE B SYSTEM WOULD NOT ENGAGE AT ALL. WE TROUBLESHOT THE PROBLEM DURING OUR ENRTE CLIMB AND DETERMINED THAT WE COULD NOT FIX EITHER AUTOPILOT. WE FLEW TO OUR DESTINATION UNEVENTFULLY WITHOUT THE AUTOPILOT. NO ALTITUDE DEVIATIONS OCCURRED AND NO REQUESTS TO CALL ATC WERE RECEIVED. WE TRADED AIRCRAFT CONTROL ONCE DURING FLIGHT TO ALLOW THE CAPTAIN TO RECHARGE PRIOR TO OUR APPROACH. WE LANDED WITHOUT INCIDENT AND HAD THE AUTOPILOT FIXED. IT OCCURRED TO ME LATER THAT DAY THAT WE SHOULD NOT HAVE FLOWN IN RVSM AIRSPACE. THE FOM TAB ON RVSM AND THE MEL ARE QUITE CLEAR ON THE SUBJECT. OUR ERROR WAS NOT INFORMING ATC THAT WE NEEDED 2000 FT OF SEPARATION. WE WERE BOTH ATTENTIVE TO MAINTAINING ALTITUDE AND NEITHER ONE OF US THOUGHT TO REFER TO THE MEL OR THE FOM. WE DID REFER TO THE QRH BUT DID NOT FIND ANY RELEVANT INFORMATION. I AS THE PNF PROBABLY SHOULD HAVE HAD THE SITUATIONAL AWARENESS TO CHECK THE FOM AND OPC. GIVEN THAT DUAL AUTOPILOT FAILURES ARE NOT A COMMON OCCURRENCE; PERHAPS A QRH PAGE THAT REPEATS THE RVSM IMPLICATIONS WOULD HAVE BEEN HELPFUL.
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.