Narrative:

After takeoff into IMC for ILS approach practice, I was vectored onto downwind by center. During my IMC ride at this point I noted only tiny deviations of heading/altitude. I had done extensive simulator practice recently, but this was my first flight in a while in actual IMC. I maintained a vigil for ice accretion on the aircraft, as the temperature was appropriate for icing. Shortly, I did, in fact, note ice (rime-mixed) beginning to accumulate. As the aircraft was not equipped with deicing equipment I elected to make approach to full stop landing rather than continue the IMC approach practice I had scheduled. With the distraction of relatively moderate ice buildup, I noted that my heading control, as well as altitude control, while being vectored for the ILS, was markedly deteriorating. This was my first experience with airframe icing. At times, I noted heading deviations of 20-30 degrees (corrected immediately) and altdevs of plus or minus 150 ft. My final vector to the localizer was a left turn to 300 degrees, an approximately 150 degree left turn. During this turn, my concentration, poor because of ice (now very noticeable), I exceeded standard rate several times. I believe the heading to intercept was 300 degrees, but I can't now be sure. After intercepting the localizer, I was cleared for the approach and I flew an uneventful approach to full stop landing. I do not believe that I deviated in altitude or heading in excess of tolerances, but the possibility exists. I am amazed at the deterioration of my normally precise instrument skills with the pressure/stress that the icing conditions created. Couple this with my first real IMC flight solo (no passenger), and you come up with a recipe for possible problems. It should be recognized that the distraction of icing, with its associated dangers, can be extreme to a pilot not intimately familiar with this phenomenon. I am amazed and distressed by the deterioration of my performance that this moderate icing provided. Several other noncritical errors (mostly in cockpit management) were induced by this phenomenon as well. Please place this warning in your literature. After training in the dangers of icing conditions, and so much warning about its dangers, one danger is not immediately apparent -- the danger that the fear of loss of control due to ice can induce loss of performance and perhaps loss of control. Fly the airplane!

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Original NASA ASRS Text

Title: PLT RPT ON THE HDG TRACK ALTDEVS EXPERIENCED DURING FIRST SOLO FLT IN IMC AND THE OBSERVATION OF ICE FORMATION ON HIS ACFT WITH THE SUBSEQUENT DETERIORATION OF PLT TECHNIQUE FLYING.

Narrative: AFTER TKOF INTO IMC FOR ILS APCH PRACTICE, I WAS VECTORED ONTO DOWNWIND BY CTR. DURING MY IMC RIDE AT THIS POINT I NOTED ONLY TINY DEVS OF HDG/ALT. I HAD DONE EXTENSIVE SIMULATOR PRACTICE RECENTLY, BUT THIS WAS MY FIRST FLT IN A WHILE IN ACTUAL IMC. I MAINTAINED A VIGIL FOR ICE ACCRETION ON THE ACFT, AS THE TEMP WAS APPROPRIATE FOR ICING. SHORTLY, I DID, IN FACT, NOTE ICE (RIME-MIXED) BEGINNING TO ACCUMULATE. AS THE ACFT WAS NOT EQUIPPED WITH DEICING EQUIP I ELECTED TO MAKE APCH TO FULL STOP LNDG RATHER THAN CONTINUE THE IMC APCH PRACTICE I HAD SCHEDULED. WITH THE DISTR OF RELATIVELY MODERATE ICE BUILDUP, I NOTED THAT MY HDG CTL, AS WELL AS ALT CTL, WHILE BEING VECTORED FOR THE ILS, WAS MARKEDLY DETERIORATING. THIS WAS MY FIRST EXPERIENCE WITH AIRFRAME ICING. AT TIMES, I NOTED HDG DEVS OF 20-30 DEGS (CORRECTED IMMEDIATELY) AND ALTDEVS OF PLUS OR MINUS 150 FT. MY FINAL VECTOR TO THE LOC WAS A L TURN TO 300 DEGS, AN APPROX 150 DEG L TURN. DURING THIS TURN, MY CONCENTRATION, POOR BECAUSE OF ICE (NOW VERY NOTICEABLE), I EXCEEDED STANDARD RATE SEVERAL TIMES. I BELIEVE THE HDG TO INTERCEPT WAS 300 DEGS, BUT I CAN'T NOW BE SURE. AFTER INTERCEPTING THE LOC, I WAS CLRED FOR THE APCH AND I FLEW AN UNEVENTFUL APCH TO FULL STOP LNDG. I DO NOT BELIEVE THAT I DEVIATED IN ALT OR HDG IN EXCESS OF TOLERANCES, BUT THE POSSIBILITY EXISTS. I AM AMAZED AT THE DETERIORATION OF MY NORMALLY PRECISE INST SKILLS WITH THE PRESSURE/STRESS THAT THE ICING CONDITIONS CREATED. COUPLE THIS WITH MY FIRST REAL IMC FLT SOLO (NO PAX), AND YOU COME UP WITH A RECIPE FOR POSSIBLE PROBS. IT SHOULD BE RECOGNIZED THAT THE DISTR OF ICING, WITH ITS ASSOCIATED DANGERS, CAN BE EXTREME TO A PLT NOT INTIMATELY FAMILIAR WITH THIS PHENOMENON. I AM AMAZED AND DISTRESSED BY THE DETERIORATION OF MY PERFORMANCE THAT THIS MODERATE ICING PROVIDED. SEVERAL OTHER NONCRITICAL ERRORS (MOSTLY IN COCKPIT MGMNT) WERE INDUCED BY THIS PHENOMENON AS WELL. PLEASE PLACE THIS WARNING IN YOUR LITERATURE. AFTER TRAINING IN THE DANGERS OF ICING CONDITIONS, AND SO MUCH WARNING ABOUT ITS DANGERS, ONE DANGER IS NOT IMMEDIATELY APPARENT -- THE DANGER THAT THE FEAR OF LOSS OF CTL DUE TO ICE CAN INDUCE LOSS OF PERFORMANCE AND PERHAPS LOSS OF CTL. FLY THE AIRPLANE!

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.