C182 pilot lost aircraft control when sct cleared him from 4000 ft to 5000 ft.

Attributes
ACN	543563
Time
Date	200204
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : sct.tracon
State Reference	CA
Altitude	msl bound lower : 3400 msl bound upper : 5000
Environment
Flight Conditions	IMC
Weather Elements	Turbulence
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sct.tracon
Operator	general aviation : personal
Make Model Name	Skylane 182/RG Turbo Skylane/RG
Operating Under FAR Part	Part 91
Flight Phase	climbout : intermediate altitude
Route In Use	enroute airway : v8.airway
Flight Plan	IFR
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 15 flight time total : 600 flight time type : 270
ASRS Report	543563
Person 2
Affiliation	government : faa
Function	controller : approach
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : weather inflight encounter : turbulence inflight encounter other non adherence : published procedure non adherence : far other anomaly other anomaly other other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued alert flight crew : regained aircraft control none taken : detected after the fact
Supplementary
Problem Areas	Weather Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While conducting an IFR flight in solid instrument conditions, I was instructed to leave my assigned altitude of 4000 ft and climb to 5000 ft. After acknowledging the instructions, I reached over to disconnect the altitude hold on the autoplt to continue the climb. Within a few seconds I found that the airplane had entered a fairly steep bank to the right and was losing altitude rapidly. The aircraft lost approximately 600 ft before I was able to return the aircraft to a wings level position and pull out of the resulting dive. I was questioned by ATC if I understood that I was to climb to 5000 ft. I replied that I understood and that I was having problems with the autoplt. I then resumed the climb to 5000 ft and leveled off at that altitude. After analyzing this event I have come to the conclusion that while reaching for the altitude on/off button, I inadvertently pushed on the heading hold knob which is located directly below the altitude hold button and may have possibly turned it right at the same time. Once the heading hold was disconnected, the plane responded by turning right sharply. There was a moderate amount of turbulence at the time which could explain why I may have hit the heading knob without realizing it. My first impression was that the autoplt had failed and after regaining my assigned altitude I spent several mins checking the system to make sure that it would function properly. The steep turn and dive apparently caused the directional gyro to precess and my attention was so focused on the autoplt that I neglected to check the directional gyro against the compass resulting in a turn at the approach course that was incorrect. The controller asked me where I was going and it was then that I realized that the directional gyro was not matching the compass. After asking for a vector I regained the proper approach course and completed the flight with no further incident by hand flying the final segment of the flight. This incident has taught me that it is better to use the yoke mounted altitude disconnect switch rather than trying to lean over and disconnect the altitude hold on the instrument itself which may lead to disorientation in turbulent solid IMC. A lesson I will not likely forgot.

Original NASA ASRS Text

Title: C182 PLT LOST ACFT CTL WHEN SCT CLRED HIM FROM 4000 FT TO 5000 FT.

Narrative: WHILE CONDUCTING AN IFR FLT IN SOLID INST CONDITIONS, I WAS INSTRUCTED TO LEAVE MY ASSIGNED ALT OF 4000 FT AND CLB TO 5000 FT. AFTER ACKNOWLEDGING THE INSTRUCTIONS, I REACHED OVER TO DISCONNECT THE ALT HOLD ON THE AUTOPLT TO CONTINUE THE CLB. WITHIN A FEW SECONDS I FOUND THAT THE AIRPLANE HAD ENTERED A FAIRLY STEEP BANK TO THE R AND WAS LOSING ALT RAPIDLY. THE ACFT LOST APPROX 600 FT BEFORE I WAS ABLE TO RETURN THE ACFT TO A WINGS LEVEL POS AND PULL OUT OF THE RESULTING DIVE. I WAS QUESTIONED BY ATC IF I UNDERSTOOD THAT I WAS TO CLB TO 5000 FT. I REPLIED THAT I UNDERSTOOD AND THAT I WAS HAVING PROBS WITH THE AUTOPLT. I THEN RESUMED THE CLB TO 5000 FT AND LEVELED OFF AT THAT ALT. AFTER ANALYZING THIS EVENT I HAVE COME TO THE CONCLUSION THAT WHILE REACHING FOR THE ALT ON/OFF BUTTON, I INADVERTENTLY PUSHED ON THE HDG HOLD KNOB WHICH IS LOCATED DIRECTLY BELOW THE ALT HOLD BUTTON AND MAY HAVE POSSIBLY TURNED IT R AT THE SAME TIME. ONCE THE HDG HOLD WAS DISCONNECTED, THE PLANE RESPONDED BY TURNING R SHARPLY. THERE WAS A MODERATE AMOUNT OF TURB AT THE TIME WHICH COULD EXPLAIN WHY I MAY HAVE HIT THE HDG KNOB WITHOUT REALIZING IT. MY FIRST IMPRESSION WAS THAT THE AUTOPLT HAD FAILED AND AFTER REGAINING MY ASSIGNED ALT I SPENT SEVERAL MINS CHKING THE SYS TO MAKE SURE THAT IT WOULD FUNCTION PROPERLY. THE STEEP TURN AND DIVE APPARENTLY CAUSED THE DIRECTIONAL GYRO TO PRECESS AND MY ATTN WAS SO FOCUSED ON THE AUTOPLT THAT I NEGLECTED TO CHK THE DIRECTIONAL GYRO AGAINST THE COMPASS RESULTING IN A TURN AT THE APCH COURSE THAT WAS INCORRECT. THE CTLR ASKED ME WHERE I WAS GOING AND IT WAS THEN THAT I REALIZED THAT THE DIRECTIONAL GYRO WAS NOT MATCHING THE COMPASS. AFTER ASKING FOR A VECTOR I REGAINED THE PROPER APCH COURSE AND COMPLETED THE FLT WITH NO FURTHER INCIDENT BY HAND FLYING THE FINAL SEGMENT OF THE FLT. THIS INCIDENT HAS TAUGHT ME THAT IT IS BETTER TO USE THE YOKE MOUNTED ALT DISCONNECT SWITCH RATHER THAN TRYING TO LEAN OVER AND DISCONNECT THE ALT HOLD ON THE INST ITSELF WHICH MAY LEAD TO DISORIENTATION IN TURBULENT SOLID IMC. A LESSON I WILL NOT LIKELY FORGOT.

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.