Narrative:

Aircraft was on an IFR flight plan from dayton, oh, to caldwell, nj. En route, a plus-minus 100' assigned altitude was consistently held except for one deviation of 400' from assigned altitude which was quickly corrected. During the final phase of flight at 2500' MSL, vectors were given to intercept localizer for runway 22 at cdw. Prior to reaching 'snafu' intersection/OM, autoplt was engaged to maintain heading hold. During scan, a deviation from heading was noticed and a correction was made to override the autoplt. The aircraft responded to correction and seemed to stabilize on course. Shortly thereafter, a serious deviation of heading, attitude and altitude was observed during which the aircraft entered a spiral descent, and losing several hundred feet of altitude. At this point, the situation became stressful in the cockpit, especially in the form of comments from the pilot/passenger on board, and it was several seconds delay before it was realized that the autoplt was malfunctioning. The switch was disengaged, a missed approach was requested and approved. The suddenness of the experience induced temporary disorientation causing difficulty in establishing a proper missed approach. Vectors were requested for another try and the approach was repeated. During this phase, the pilot/passenger misunderstood my comment about use of the autoplt and re-engaged it. Simultaneously, he and I were engaged in argument about the approach procedures depicted on the approach plate. Consequently, a repeat of the initial approach difficulties occurred including entry into spirals and altitude deviations of several hundred ft. The autoplt was once again disengaged, the approach concluded by hand flying with breakout at runway heading and in position for a circling approach to land on runway 4. It is my belief that performance in the cockpit was caused by malfunction of the autoplt, influence of peer on board whose opinion was highly respected but should have been withheld from cockpit discussion until after flight debriefing. It is pertinent to point out that the aircraft was flown immediately after an annual inspection during which a circuit breaker inside the panel was (erroneously) replaced. I personally observed during the annual that in trying to gain access to the breaker, wire bundles were pulled with such force as to cause a terminal from the landing gear indicator light switch to separate. The autoplt switch is in he same bundle of wires and it is assumed that the cause of malfunction will be found in the same area of abuse where there are a number of autoplt connectors. The quality of maintenance requires reinspection by the owner who in many cases is as qualified as the mechanic who performs the inspection. This is especially true in this case where the same airplane has been solely owned, studied and flown for seventeen yrs. Training for IFR flying should emphasize the applicant's need to be forceful as well as tactful in establishing the appropriate rules of flying with passengers of unusual qualification who, although respected, are not the PIC. Lack of such protocol was already evident when it coincided with the brief en route altitude deviation during a spirited cockpit exchange concerning en route procedures.

Related reports:

Google
 

Original NASA ASRS Text

Title: SMA WITH AUTOPLT PROBLEM AND CONTEST OF WILL BETWEEN PLT AND PASSENGER EXPERIENCES LOSS OF ACFT CTL, HEADING AND TRACK DEVIATION, ALT EXCURSIONS.

Narrative: ACFT WAS ON AN IFR FLT PLAN FROM DAYTON, OH, TO CALDWELL, NJ. ENRTE, A PLUS-MINUS 100' ASSIGNED ALT WAS CONSISTENTLY HELD EXCEPT FOR ONE DEV OF 400' FROM ASSIGNED ALT WHICH WAS QUICKLY CORRECTED. DURING THE FINAL PHASE OF FLT AT 2500' MSL, VECTORS WERE GIVEN TO INTERCEPT LOC FOR RWY 22 AT CDW. PRIOR TO REACHING 'SNAFU' INTXN/OM, AUTOPLT WAS ENGAGED TO MAINTAIN HDG HOLD. DURING SCAN, A DEV FROM HDG WAS NOTICED AND A CORRECTION WAS MADE TO OVERRIDE THE AUTOPLT. THE ACFT RESPONDED TO CORRECTION AND SEEMED TO STABILIZE ON COURSE. SHORTLY THEREAFTER, A SERIOUS DEV OF HDG, ATTITUDE AND ALT WAS OBSERVED DURING WHICH THE ACFT ENTERED A SPIRAL DSNT, AND LOSING SEVERAL HUNDRED FEET OF ALT. AT THIS POINT, THE SITUATION BECAME STRESSFUL IN THE COCKPIT, ESPECIALLY IN THE FORM OF COMMENTS FROM THE PLT/PAX ON BOARD, AND IT WAS SEVERAL SECS DELAY BEFORE IT WAS REALIZED THAT THE AUTOPLT WAS MALFUNCTIONING. THE SWITCH WAS DISENGAGED, A MISSED APCH WAS REQUESTED AND APPROVED. THE SUDDENNESS OF THE EXPERIENCE INDUCED TEMPORARY DISORIENTATION CAUSING DIFFICULTY IN ESTABLISHING A PROPER MISSED APCH. VECTORS WERE REQUESTED FOR ANOTHER TRY AND THE APCH WAS REPEATED. DURING THIS PHASE, THE PLT/PAX MISUNDERSTOOD MY COMMENT ABOUT USE OF THE AUTOPLT AND RE-ENGAGED IT. SIMULTANEOUSLY, HE AND I WERE ENGAGED IN ARGUMENT ABOUT THE APCH PROCS DEPICTED ON THE APCH PLATE. CONSEQUENTLY, A REPEAT OF THE INITIAL APCH DIFFICULTIES OCCURRED INCLUDING ENTRY INTO SPIRALS AND ALT DEVS OF SEVERAL HUNDRED FT. THE AUTOPLT WAS ONCE AGAIN DISENGAGED, THE APCH CONCLUDED BY HAND FLYING WITH BREAKOUT AT RWY HDG AND IN POS FOR A CIRCLING APCH TO LAND ON RWY 4. IT IS MY BELIEF THAT PERFORMANCE IN THE COCKPIT WAS CAUSED BY MALFUNCTION OF THE AUTOPLT, INFLUENCE OF PEER ON BOARD WHOSE OPINION WAS HIGHLY RESPECTED BUT SHOULD HAVE BEEN WITHHELD FROM COCKPIT DISCUSSION UNTIL AFTER FLT DEBRIEFING. IT IS PERTINENT TO POINT OUT THAT THE ACFT WAS FLOWN IMMEDIATELY AFTER AN ANNUAL INSPECTION DURING WHICH A CB INSIDE THE PANEL WAS (ERRONEOUSLY) REPLACED. I PERSONALLY OBSERVED DURING THE ANNUAL THAT IN TRYING TO GAIN ACCESS TO THE BREAKER, WIRE BUNDLES WERE PULLED WITH SUCH FORCE AS TO CAUSE A TERMINAL FROM THE LNDG GEAR INDICATOR LIGHT SWITCH TO SEPARATE. THE AUTOPLT SWITCH IS IN HE SAME BUNDLE OF WIRES AND IT IS ASSUMED THAT THE CAUSE OF MALFUNCTION WILL BE FOUND IN THE SAME AREA OF ABUSE WHERE THERE ARE A NUMBER OF AUTOPLT CONNECTORS. THE QUALITY OF MAINT REQUIRES REINSPECTION BY THE OWNER WHO IN MANY CASES IS AS QUALIFIED AS THE MECH WHO PERFORMS THE INSPECTION. THIS IS ESPECIALLY TRUE IN THIS CASE WHERE THE SAME AIRPLANE HAS BEEN SOLELY OWNED, STUDIED AND FLOWN FOR SEVENTEEN YRS. TRNING FOR IFR FLYING SHOULD EMPHASIZE THE APPLICANT'S NEED TO BE FORCEFUL AS WELL AS TACTFUL IN ESTABLISHING THE APPROPRIATE RULES OF FLYING WITH PAXS OF UNUSUAL QUALIFICATION WHO, ALTHOUGH RESPECTED, ARE NOT THE PIC. LACK OF SUCH PROTOCOL WAS ALREADY EVIDENT WHEN IT COINCIDED WITH THE BRIEF ENRTE ALT DEVIATION DURING A SPIRITED COCKPIT EXCHANGE CONCERNING ENRTE PROCS.

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.