Narrative:

Small transport was cleared for an IFR departure, runway heading 19L at iad on file to ilg. The tower handed us over to departure. Departure told me to turn right to a specific heading. I did, and after about 15 seconds on that heading, departure came on and said 'small transport I told you to be on a heading of XXX.' I then realized that the directional gyroscope was on the fritz (it appeared as if the magnetic slaving unit was not dong its job). I told departure of my situation and he gave me another heading. Timing the turn (or trying to, it was continuous chop and I was still climbing), I turned to this new heading. Again, the controller came on and said 'small transport I want you on this heading.' I told him again that I was having problems and by this time my altitude was now 500 ft about what I was assigned. I was correcting the altitude problem as the controller came back on and advised me of my altitude variation. Again, he gave me a new heading. Then he asked if I was having gyroscope problems. At this moment I snapped back and said 'yes, for the 3RD time, yes, I am having a problem with my gyroscope.' (I am now at 7000 ft and in and out of IMC building cumulu nimbus.) after this, things started to slow down as he gave me 'no gyroscope turns' then I tried to resolve the situation in straight and level flight, but I was unable to do so. I returned back to iad because approach control would not allow no gyroscopes to ilg. I landed iad and looked for an avionics technician (with no luck). Because the WX was definitely improving, I decided to go VFR to ilg where repairs would be attempted. My final destination was 3b2. I departed iad VFR. Clearance was advised of the situation and told me he would work out handoffs for this flight ('the whole way'). Well, their intentions were good, but my mistake was to rely on this. Departure control's workload got too heavy and they were unable to work out a handoff. So, they told me to remain clear of the TCA, radar service terminated, and resumed own navigation. (However, just before he was about to terminate radar service, I noticed that the nose gear was still down but the mains were up -- what a day!) I paused and repeated what he said, but he then (30 seconds) came back on and told me I was in the TCA and approach wanted to talk to me. I contacted approach, told them of my intentions, destination and requested 9500 ft. Without hesitation they cleared me to 9500 ft. After I leveled off the controller asked me to copy a phone number and his name and to contact him when I landed. At XA30Z I phoned him and we worked things out over the phone. When he realized that I actually knew what I was doing he told me that everything is ok and not to worry about a violation. In summary: I feel that I could have avoided the situation had I made it clear to the controller that I was in need of continued flight following due to an unreliable directional gyroscope and not to allow him to terminate radar service, which was requested to iad clearance delivery.

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Original NASA ASRS Text

Title: SMT HAS GYROSCOPE FAILURE ON IFR FLT PLAN IN MIXED CONDITIONS. RETURN LAND.

Narrative: SMT WAS CLRED FOR AN IFR DEP, RWY HDG 19L AT IAD ON FILE TO ILG. THE TWR HANDED US OVER TO DEP. DEP TOLD ME TO TURN R TO A SPECIFIC HDG. I DID, AND AFTER ABOUT 15 SECONDS ON THAT HDG, DEP CAME ON AND SAID 'SMT I TOLD YOU TO BE ON A HDG OF XXX.' I THEN REALIZED THAT THE DIRECTIONAL GYROSCOPE WAS ON THE FRITZ (IT APPEARED AS IF THE MAGNETIC SLAVING UNIT WAS NOT DONG ITS JOB). I TOLD DEP OF MY SIT AND HE GAVE ME ANOTHER HDG. TIMING THE TURN (OR TRYING TO, IT WAS CONTINUOUS CHOP AND I WAS STILL CLBING), I TURNED TO THIS NEW HDG. AGAIN, THE CTLR CAME ON AND SAID 'SMT I WANT YOU ON THIS HDG.' I TOLD HIM AGAIN THAT I WAS HAVING PROBS AND BY THIS TIME MY ALT WAS NOW 500 FT ABOUT WHAT I WAS ASSIGNED. I WAS CORRECTING THE ALT PROB AS THE CTLR CAME BACK ON AND ADVISED ME OF MY ALT VARIATION. AGAIN, HE GAVE ME A NEW HDG. THEN HE ASKED IF I WAS HAVING GYROSCOPE PROBS. AT THIS MOMENT I SNAPPED BACK AND SAID 'YES, FOR THE 3RD TIME, YES, I AM HAVING A PROB WITH MY GYROSCOPE.' (I AM NOW AT 7000 FT AND IN AND OUT OF IMC BUILDING CUMULU NIMBUS.) AFTER THIS, THINGS STARTED TO SLOW DOWN AS HE GAVE ME 'NO GYROSCOPE TURNS' THEN I TRIED TO RESOLVE THE SIT IN STRAIGHT AND LEVEL FLT, BUT I WAS UNABLE TO DO SO. I RETURNED BACK TO IAD BECAUSE APCH CTL WOULD NOT ALLOW NO GYROSCOPES TO ILG. I LANDED IAD AND LOOKED FOR AN AVIONICS TECHNICIAN (WITH NO LUCK). BECAUSE THE WX WAS DEFINITELY IMPROVING, I DECIDED TO GO VFR TO ILG WHERE REPAIRS WOULD BE ATTEMPTED. MY FINAL DEST WAS 3B2. I DEPARTED IAD VFR. CLRNC WAS ADVISED OF THE SIT AND TOLD ME HE WOULD WORK OUT HDOFS FOR THIS FLT ('THE WHOLE WAY'). WELL, THEIR INTENTIONS WERE GOOD, BUT MY MISTAKE WAS TO RELY ON THIS. DEP CTL'S WORKLOAD GOT TOO HVY AND THEY WERE UNABLE TO WORK OUT A HDOF. SO, THEY TOLD ME TO REMAIN CLR OF THE TCA, RADAR SVC TERMINATED, AND RESUMED OWN NAV. (HOWEVER, JUST BEFORE HE WAS ABOUT TO TERMINATE RADAR SVC, I NOTICED THAT THE NOSE GEAR WAS STILL DOWN BUT THE MAINS WERE UP -- WHAT A DAY!) I PAUSED AND REPEATED WHAT HE SAID, BUT HE THEN (30 SECONDS) CAME BACK ON AND TOLD ME I WAS IN THE TCA AND APCH WANTED TO TALK TO ME. I CONTACTED APCH, TOLD THEM OF MY INTENTIONS, DEST AND REQUESTED 9500 FT. WITHOUT HESITATION THEY CLRED ME TO 9500 FT. AFTER I LEVELED OFF THE CTLR ASKED ME TO COPY A PHONE NUMBER AND HIS NAME AND TO CONTACT HIM WHEN I LANDED. AT XA30Z I PHONED HIM AND WE WORKED THINGS OUT OVER THE PHONE. WHEN HE REALIZED THAT I ACTUALLY KNEW WHAT I WAS DOING HE TOLD ME THAT EVERYTHING IS OK AND NOT TO WORRY ABOUT A VIOLATION. IN SUMMARY: I FEEL THAT I COULD HAVE AVOIDED THE SIT HAD I MADE IT CLR TO THE CTLR THAT I WAS IN NEED OF CONTINUED FLT FOLLOWING DUE TO AN UNRELIABLE DIRECTIONAL GYROSCOPE AND NOT TO ALLOW HIM TO TERMINATE RADAR SVC, WHICH WAS REQUESTED TO IAD CLRNC DELIVERY.

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.