A C172 pilot experienced vertigo due to vacuum failure, after entering IMC while talking to phl.

Attributes
ACN	586662
Time
Date	200307
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : ard.vor
State Reference	PA
Altitude	msl single value : 3000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : phl.tracon tracon : tpa.tracon
Operator	Other
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Route In Use	enroute airway : v276.airway
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : multi engine pilot : cfi pilot : commercial pilot : instrument
Experience	flight time last 90 days : 40 flight time total : 2118 flight time type : 600
ASRS Report	586662
Person 2
Affiliation	government : faa
Function	controller : approach
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper documentation maintenance problem : improper maintenance non adherence : clearance other anomaly other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued alert flight crew : regained aircraft control flight crew : overcame equipment problem flight crew : became reoriented
Consequence	other other
Supplementary
Problem Areas	Flight Crew Human Performance Weather Aircraft
Primary Problem	Flight Crew Human Performance

Narrative:

I had just entered IMC, the attitude indicator and heading indicator badly processed. Approach asked if everything was ok, because my aircraft appeared to be doing s-turns. The attitude indicator showed me in a 30 degree turn. The call from approach was a wake-up call. Prior to the call, I was feeling an oncoming vertigo and a queasiness in my stomach. ATC got my attention, and I started a full instrument scan. I put much emphasis on the turn coordinator and altimeter, and airspeed indicator. After that, I settled down. I think part of my problem was that I have gotten too used to the avionics in my flying club's mooney M20J (kfc iso and garmin +30), and cirrus SR20 (HSI garmin +30), and subsequently got behind the airplane when flying a 'no frills' very basic airplane. I later learned from another pilot that spins had been done in this airplane, and that other pilots didn't trust the instruments due to attitude indicator and heading indicator precession. I got back on the horse the next day, and hand-flew the SR20 in haze bad enough to be IMC. I had no trouble using them on approach.

Original NASA ASRS Text

Title: A C172 PLT EXPERIENCED VERTIGO DUE TO VACUUM FAILURE, AFTER ENTERING IMC WHILE TALKING TO PHL.

Narrative: I HAD JUST ENTERED IMC, THE ATTITUDE INDICATOR AND HDG INDICATOR BADLY PROCESSED. APCH ASKED IF EVERYTHING WAS OK, BECAUSE MY ACFT APPEARED TO BE DOING S-TURNS. THE ATTITUDE INDICATOR SHOWED ME IN A 30 DEG TURN. THE CALL FROM APCH WAS A WAKE-UP CALL. PRIOR TO THE CALL, I WAS FEELING AN ONCOMING VERTIGO AND A QUEASINESS IN MY STOMACH. ATC GOT MY ATTN, AND I STARTED A FULL INST SCAN. I PUT MUCH EMPHASIS ON THE TURN COORDINATOR AND ALTIMETER, AND AIRSPD INDICATOR. AFTER THAT, I SETTLED DOWN. I THINK PART OF MY PROB WAS THAT I HAVE GOTTEN TOO USED TO THE AVIONICS IN MY FLYING CLUB'S MOONEY M20J (KFC ISO AND GARMIN +30), AND CIRRUS SR20 (HSI GARMIN +30), AND SUBSEQUENTLY GOT BEHIND THE AIRPLANE WHEN FLYING A 'NO FRILLS' VERY BASIC AIRPLANE. I LATER LEARNED FROM ANOTHER PLT THAT SPINS HAD BEEN DONE IN THIS AIRPLANE, AND THAT OTHER PLTS DIDN'T TRUST THE INSTS DUE TO ATTITUDE INDICATOR AND HDG INDICATOR PRECESSION. I GOT BACK ON THE HORSE THE NEXT DAY, AND HAND-FLEW THE SR20 IN HAZE BAD ENOUGH TO BE IMC. I HAD NO TROUBLE USING THEM ON APCH.

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.