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Incidents related to Issue 5 incidents related to this issue.

Issue: inadvertent autopilot disengagement may be too easy (Issue #123)
Description: It may be too easy for the pilot to inadvertently disengage the autopilot. When this happens, control may be lost.

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  2. Accession Number: 362571
    Synopsis: PIC OF AN MLG SETS COCKPIT UP FOR A CAT III APCH. SELECTS #2 AUTOPLT PRIOR TO ARMING THE APCH MODE. AUTOPLTS DISCONNECT AND ACFT GOES THROUGH LOC, CREATING A POTENTIAL CONFLICT LTSS WITH ACFT Y.
    Narrative: FOR CERTIFICATION PURPOSES IT WAS DECIDED THAT THE CAPT (PF) WOULD EXECUTE THE CAT III AUTOLAND TO RWY 36L AT CVG. CONDITIONS WERE DAYTIME AND VFR, APCH AGREED TO OUR REQUEST. AFTER BEING GIVEN A HEADING TO INTERCEPT THE FINAL APCH COURSE THE CAPT SELECTED THE SECOND AUTOPLT BEFORE ARMING THE 'APCH MODE.' THIS WAS INCORRECT AND CAUSED BOTH AUTOPLTS TO DISENGAGE. THIS THEN LED TO SOME CONFUSION IN THE COCKPIT AS WE ATTEMPTED TO CORRECT THE PROB. DURING THIS TIME WE WERE STILL ON OUR ASSIGNED INTERCEPT HEADING AND ULTIMATELY OVERSHOT THE FINAL APCH COURSE. THERE WAS PARALLEL TFC INBOUND TO RWY 36R WHICH WE CAME WITHIN 1 MI OF AND LED TO A TA FROM TCASII. AT THIS TIME WE ABANDONED THE AUTOLAND APCH, CORRECTED BACK TO THE FINAL APCH COURSE AND CONTINUED A MANUAL APCH. NO EVASIVE ACTION WAS NEEDED. THE DISENGAGEMENT OF THE BOTH AUTOPLTS WAS A DISTR FOR BOTH OF US WHICH LED TO REDUCED SITUATIONAL AWARENESS. SUPPLEMENTAL INFO FROM ACN 362570: I DECIDED TO FLY AN AUTOLAND APCH IN ORDER TO FINISH MY CERTIFICATION FOR CAT III OPS.

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  4. Accession Number: 368799
    Synopsis: DC10 DSNDING TO 6000 FT. FO, PF, INADVERTENTLY GOT INTO VERT SPD MODE ON THE AUTOPLT RESULTING IN OVERSHOOTING ALT 300 FT.
    Narrative: ALTDEV OF ABOUT 350 FT. WE HAD BEEN CLRED FROM 8000 FT TO 6000 FT. FO FLYING, AUTOPLT ENGAGED. WE ALL OBSERVED ALT CAPTURE ON FMA AT ABOUT 6400 FT, HOWEVER, A FEW SECONDS LATER THE ALT WAS OBSERVED AT 5700 FT WITH ACFT STILL IN A SHALLOW DSCNT AND AUTOPLT IN VERT SPD MODE. AN IMMEDIATE CLB WAS INITIATED BACK TO 6000 FT. WE DON'T KNOW WHETHER FO ACCIDENTALLY BUMPED VERT SPD KNOB AFTER ALT CAPTURE, OR IF AUTOPLT LOST CAPTURE DUE TO TURB. REVIEWED PROPER AUTOPLT TECHNIQUE WITH FO AND CAUTIONED HIM TO KEEP HAND AWAY FROM VERT SPD KNOB AFTER ALT CAPTURE. SUPPLEMENTAL INFO FROM ACN 368990: WE WERE IN MODERATE TURB DUE TO ASSOCIATED BUILDUPS OF TSTMS AT THE TIME.

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  6. Accession Number: 398228
    Synopsis: CL6013A ACFT IN CLB TO 10000 FT ENCOUNTERED CLR AIR TURB JUST PRIOR TO LEVELOFF. AUTOPLT KICKED OFF AND ACFT WENT ABOVE ASSIGNED ALT INTERFERING WITH ANOTHER ACFT CREATING A LOSS OF SEPARATION.
    Narrative: I WAS A PNF IN THE L SEAT OF A CANADAIR CHALLENGER 601/3A THAT HAD AN ALT OVERSHOOT AT 10000 FT MSL ON DEP OUT OF DTW. THE FOLLOWING SERIES OF EVENTS OCCURRED: 1) WE WERE LEVEL AT 7000 FT MSL IN MOSTLY LIGHT TURB FROM THE START OF THE FLT. 2) DTW DEP CLRED US TO 10000 FT MSL. ON THE READBACK I SAID 12000 FT MSL AND WAS CORRECTED BY ATC. I ACKNOWLEDGED THE 10000 FT MSL AND SET 10000 FT MSL IN THE ALT PRESELECT. 3) THE PF IN THE R SEAT HAD THE ACFT ON AUTOPLT AND INITIATED A CLB ON THE AUTOPLT TO 10000 FT MSL. 4) WE WERE JUST PRIOR TO OUR LEVELOUT AT 10000 FT MSL WHEN WE EXPERIENCED A MODERATE JOLT ON THE CTL YOKE FROM CLR AIR TURB. THE AUTOPLT DISENGAGED AS WE WERE IN A PITCH UP CLB. 5) THE PF TOOK OVER FLYING MANUALLY AND MADE A SMOOTH RECOVERY. AT THE SAME TIME, A BRIEF SLOW RESOLUTION DSCNT CALLOUT OCCURRED LASTING NO MORE THAN A FEW SECONDS. WE OBSERVED THE ALTIMETER PASSING THROUGH 10300 FT MSL ON THE RECOVERY AND FEEL WE COULD HAVE GOTTEN AS HIGH AS 10500 FT, BUT WE ARE NOT POSITIVE OF THIS. THE RA WE OBSERVED ON THE TCASII FROM WHAT WE COULD DETERMINE WAS FROM AN ACFT OUTSIDE OF OUR 3 MI CIRCLE, AT OUR 2-3 O'CLOCK POS, AT 11000 FT MSL. THE TFC WAS EITHER FLYING PARALLEL TO US OR AWAY FROM US. THERE WAS NO TIME DURING THIS PERIOD THAT WE OBSERVED ANY TFC WITHIN OUR TCASII 3 MI CIRCLE. WE WERE VMC AT THIS TIME AND DIDN'T OBSERVE ANY TFC OUTSIDE VISUALLY. 6) I ACKNOWLEDGED TO ATC THAT WE WERE GETTING OUR PLANE UNDER CTL AND LEVELING AT 10000 FT MSL. THE CTLR ACKNOWLEDGED US LEVELING AT 10000 FT MSL. HE IMMEDIATELY GAVE US A CLB TO A HIGHER ALT WITH A FREQ CHANGE AND SAID GOOD DAY. 7) DTW MEANWHILE HAD GOTTEN A TCASII RA FEEDBACK FROM A SAAB COMMUTER ACFT THAT WAS ON ANOTHER FREQ. I BELIEVE THEY CORRELATED THIS TO BE THE ACFT THAT WE OBSERVED AT OUR 2- 3 O'CLOCK POS AT GREATER THAN 3 MI TO US, AT 11000 FT MSL. DTW FORWARDED A MESSAGE TO US THROUGH ZOB TO CALL. 8) DTW DEP ADVISED ME OF THE SAAB COMMUTER RESOLUTION ALERT RPT. I TOLD THE DTW SUPVR OF OUR INTENTION TO LEVEL AT 10000 FT MSL, UNTIL THE ACFT WAS DISTURBED FROM ITS FLT BY TURB. HE DIDN'T INDICATE THAT ANYTHING SERIOUS HAD HAPPENED, OTHER THAN HE INTENDED TO FILE A RPT WITH THE ENFORCEMENT AUTHS. I ADVISED HIM THAT I WOULD FILE A NASA RPT. 9) THE HUMAN FACTORS INVOLVED AT THE TIME WERE NORMAL COCKPIT DUTIES. WE CAN'T PINPOINT IF IT WAS TURB OR THE YOKE MOVEMENT THAT CAUSED AUTOPLT DISCONNECT. 10) I AM PERSONALLY GLAD THAT THERE WAS NO MORE DEV FROM OUR FLT PATH THAN OCCURRED. I THANK YOU FOR YOUR TIME IN HANDLING THIS RPT.

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  8. Accession Number: 411470
    Synopsis: FK10 CREW PENETRATED RESTR AIRSPACE (R-2601).
    Narrative: R-2601 PENETRATION. DSNDING INTO COS, FO FLYING RECEIVED HEADING TO INTERCEPT BRK 168 DEG RADIAL INBOUND. SAW FO CORRECTLY SET UP FMS AND RAW DATA AND NAV ENGAGED. I LEFT COCKPIT BRIEFLY. ON RETURN WAS BRIEFED ON ALT CHANGE. FO HAD SOME DIFFICULTY STOWING OXYGEN MASK. WHILE BRIEFING WX, TERRAIN, AND APCH RECEIVED TFC CALL FROM ZDV LOW SECTOR AND FLEW THROUGH RADIAL, WHILE SEARCHING FOR TFC, AND BRIEFING TERRAIN AHEAD. AFTER AN INQUIRY ABOUT THE RADIAL CTR ISSUED A R TURN. TURN STARTED ON AUTOPLT GAVE LESS THAN 20 DEG BANK. TURN RATE INCREASED WHEN NEXT CALL SOUNDED MORE URGENT. WAS SOME CONFUSION ABOUT IF ANOTHER HEADING HAD BEEN GIVEN AFTER INTERCEPT. WE WERE BOTH AWARE OF THE RESTR AREA BUT NOT OF ITS STATUS (HOT OR NOT). AT THE TIME THE TFC AND TERRAIN WERE THE HIGHER PRIORITIES. WE HAD ENTERED R-2601 APPROX 1.8 NM. I BELIEVE THAT THE FAILURE TO INTERCEPT WAS A COMBINATION OF UNCERTAINTY OF THE CLRNC AND AN UNDESIRED LOSS OF NAV MODE ENGAGEMENT. MOST LIKELY DURING AN ALT CHANGE, THE HEADING KNOB WAS BUMPED. WHAT TO DO DIFFERENTLY NEXT TIME: MAKE SURE OF A COMPLETE BRIEFING UPON RETURNING TO THE COCKPIT EVEN IF INTERRUPTED. RECHK FMA INDICATIONS MORE FREQUENTLY EVEN IF NO CHANGE, BE MORE ASSERTIVE AS THE PNF/CAPT AND QUICKER TO TAKE OVER CTLS WHEN MORE AGGRESSIVE MANEUVER IS NEEDED.

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  10. Accession Number: 411791
    Synopsis: A B737, LOST 800 FT IN THE HOLDING PATTERN AT FL410 WHEN THE CAPT SELECTED LNAV FOR THE TURN BACK INBOUND TO THE VOR. THE AUTOPLT HAD DISENGAGED DURING THE ENSUING 30 DEG BANK.
    Narrative: AFTER PASSING GLOVR AND WHILE ON THE OUTBOUND HOLDING LEG, THE LNAV WAS ENGAGED AND ACFT TURNED INTO A 30 DEG ANGLE OF BANK TO GET ON THE INBOUND LEG. SUDDENLY, THE AUTOPLT DISENGAGED, THE NOSE DROPPED AND ACFT LOST 800 FT IN SECONDS. I DISENGAGED THE AUTOTHROTTLE CLBED UP TO 41000 FT AND RESUMED HOLDING.
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