C182 pilot on IFR flight plan in VMC experienced attitude indicator failure and elected to continue ...

Narrative:

My attitude indicator failed in-flight; in IMC; approximately 70 miles southwest of my destination. Weather was reported in the area as 2900 broken and 4000 ovc with 7 mi visibility which should have allowed for a visual approach. After determining weather from 2 stations which confirmed each other; I elected to continue since it should have been a brief descent through IMC which did not strike me as unsafe with partial panel situation; provided the approach was to be conducted in VMC. However; weather conditions deteriorated significantly in the next 30 minutes and I was still IMC 3 mi from the airport at the lowest altitude that approach could give me; 2300 MSL. Rain and light turbulence were making partial panel IFR challenging and my headings and altitude were deviating. I notified ATC of the malfunctioning ai; but elected not to declare an emergency. I requested vectors for the VOR/GPS approach to try and get a controlled descent to VMC; since this seemed a faster route to visual conditions than returning to the south with indeterminate weather. The approach was successfully executed and I broke out at 1300 MSL (800 AGL) and was able to land. However; again due to partial panel indications compounded by light to moderate turbulence; my headings and altitude were deviating from ATC clearance; heading up to 25 degrees and altitude up to 200 ft. The chain of instrument failure; unexpectedly low ceilings and my own lack of very recent partial panel experience all led to imprecise IFR flight and likely reduced safety margins. To prevent a recurrence; additional focus on partial-panel proficiency and a more conservative view of weather in the event of a near-emergency to keep the situation from deteriorating would have been advisable; and at the initial indication of ai failure; I should probably have requested vectors to the nearest airport reporting VMC.

Original NASA ASRS Text

Title: C182 pilot on IFR flight plan in VMC experienced attitude indicator failure and elected to continue to destination. Weather at destination was worse than forecast requiring a partial panel VOR/GPS approach with significant altitude and heading deviations to get below the ceiling at 800 FT AGL.

Narrative: My attitude indicator failed in-flight; in IMC; approximately 70 miles SW of my destination. Weather was reported in the area as 2900 BKN and 4000 OVC with 7 MI visibility which should have allowed for a visual approach. After determining weather from 2 stations which confirmed each other; I elected to continue since it should have been a brief descent through IMC which did not strike me as unsafe with partial panel situation; provided the approach was to be conducted in VMC. However; weather conditions deteriorated significantly in the next 30 minutes and I was still IMC 3 MI from the airport at the lowest altitude that approach could give me; 2300 MSL. Rain and light turbulence were making partial panel IFR challenging and my headings and altitude were deviating. I notified ATC of the malfunctioning AI; but elected not to declare an emergency. I requested vectors for the VOR/GPS approach to try and get a controlled descent to VMC; since this seemed a faster route to visual conditions than returning to the south with indeterminate weather. The approach was successfully executed and I broke out at 1300 MSL (800 AGL) and was able to land. However; again due to partial panel indications compounded by light to moderate turbulence; my headings and altitude were deviating from ATC clearance; heading up to 25 degrees and altitude up to 200 FT. The chain of instrument failure; unexpectedly low ceilings and my own lack of very recent partial panel experience all led to imprecise IFR flight and likely reduced safety margins. To prevent a recurrence; additional focus on partial-panel proficiency and a more conservative view of weather in the event of a near-emergency to keep the situation from deteriorating would have been advisable; and at the initial indication of AI failure; I should probably have requested vectors to the nearest airport reporting VMC.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	857535
Time
Date	200910
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Make Model Name	Skylane 182/RG Turbo Skylane/RG
Operating Under FAR Part	Part 91
Flight Phase	Final Approach Initial Approach Descent
Route In Use	Direct
Flight Plan	IFR
Component
Aircraft Component	Attitude Indicator(Gyro/Horizon/ADI)
Person 1
Function	Single Pilot Pilot Flying
Qualification	Flight Crew Commercial Flight Crew Flight Instructor Flight Crew Instrument
Experience	Flight Crew Last 90 Days 79 Flight Crew Total 755 Flight Crew Type 270
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance Deviation - Track / Heading All Types

C182 pilot on IFR flight plan in VMC experienced attitude indicator failure and elected to continue to destination. Weather at destination was worse than forecast requiring a partial panel VOR/GPS approach with significant altitude and heading deviations to get below the ceiling at 800 ft AGL.