Narrative:

I was approximately 10 mi southeast of eug airport, VFR between layers. My destination was hio airport and reporting 3000 ft overcast and 20 mi visibility. I requested an IFR clearance to hio and eug approach said they would work on it and to stand by and remain VFR. The visibility deteriorated and I was IMC. I asked eug approach how my clearance was coming and that I could no longer maintain VFR. Approach gave me a squawk and made radar contact and cleared me to 6000 ft MSL. During that transmission I made corrections to maintain control of the airplane based on information I was seeing on my attitude indicator. I soon discovered that I was receiving erroneous information from my airspeed indicator and I was in an unusual attitude and had no suction, therefore rendering my airspeed indicator and directional gyroscope inoperative. The vacuum pump was working from pretkof until that point. I quickly informed approach I had no gyroscopes and requested no gyroscope and requested turns to vectors to hio. During the next 15-20 mins I had difficulty keeping the aircraft on a specific heading and holding altitude. I attribute this to distrs from tuning in the LORAN to hio and giving me tracking information while maintaining control of the airplane under partial panel circumstances. The rest of the remaining 40 mins to hio in IMC was without a problem due to no further cockpit distrs and additional navigation information from the properly set LORAN. I may add that the professionalism of the eug controller was excellent and that he did an outstanding job on the no gyroscope turns instructions. This was a good example of how a routine flight can become very challenging, very quickly, and how all the practice and skills a pilot possesses is put to the test. The vacuum pump has been replaced, and all system and instruments have been recertified for IFR.

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Original NASA ASRS Text

Title: GYROSCOPES FAILED IN IMC.

Narrative: I WAS APPROX 10 MI SE OF EUG ARPT, VFR BTWN LAYERS. MY DEST WAS HIO ARPT AND RPTING 3000 FT OVCST AND 20 MI VISIBILITY. I REQUESTED AN IFR CLRNC TO HIO AND EUG APCH SAID THEY WOULD WORK ON IT AND TO STAND BY AND REMAIN VFR. THE VISIBILITY DETERIORATED AND I WAS IMC. I ASKED EUG APCH HOW MY CLRNC WAS COMING AND THAT I COULD NO LONGER MAINTAIN VFR. APCH GAVE ME A SQUAWK AND MADE RADAR CONTACT AND CLRED ME TO 6000 FT MSL. DURING THAT XMISSION I MADE CORRECTIONS TO MAINTAIN CTL OF THE AIRPLANE BASED ON INFO I WAS SEEING ON MY ATTITUDE INDICATOR. I SOON DISCOVERED THAT I WAS RECEIVING ERRONEOUS INFO FROM MY AIRSPD INDICATOR AND I WAS IN AN UNUSUAL ATTITUDE AND HAD NO SUCTION, THEREFORE RENDERING MY AIRSPD INDICATOR AND DIRECTIONAL GYROSCOPE INOP. THE VACUUM PUMP WAS WORKING FROM PRETKOF UNTIL THAT POINT. I QUICKLY INFORMED APCH I HAD NO GYROSCOPES AND REQUESTED NO GYROSCOPE AND REQUESTED TURNS TO VECTORS TO HIO. DURING THE NEXT 15-20 MINS I HAD DIFFICULTY KEEPING THE ACFT ON A SPECIFIC HDG AND HOLDING ALT. I ATTRIBUTE THIS TO DISTRS FROM TUNING IN THE LORAN TO HIO AND GIVING ME TRACKING INFO WHILE MAINTAINING CTL OF THE AIRPLANE UNDER PARTIAL PANEL CIRCUMSTANCES. THE REST OF THE REMAINING 40 MINS TO HIO IN IMC WAS WITHOUT A PROB DUE TO NO FURTHER COCKPIT DISTRS AND ADDITIONAL NAV INFO FROM THE PROPERLY SET LORAN. I MAY ADD THAT THE PROFESSIONALISM OF THE EUG CTLR WAS EXCELLENT AND THAT HE DID AN OUTSTANDING JOB ON THE NO GYROSCOPE TURNS INSTRUCTIONS. THIS WAS A GOOD EXAMPLE OF HOW A ROUTINE FLT CAN BECOME VERY CHALLENGING, VERY QUICKLY, AND HOW ALL THE PRACTICE AND SKILLS A PLT POSSESSES IS PUT TO THE TEST. THE VACUUM PUMP HAS BEEN REPLACED, AND ALL SYS AND INSTS HAVE BEEN RECERTIFIED FOR IFR.

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.