Narrative:

I was being vectored onto the arrival ILS 9 approach. Chicago approach vectored me across the final approach course from north to south. Since the approach does not have DME and the jot VOR was OTS I was having problems determining my position in relation to the OM wolff. After passing through the final approach course on a heading of 180 degrees I was then told to turn to right to a heading of 070 degrees and descend and maintain 3000 (I had been at 4000). Shortly after I had completed the turn chicago approach told me heading 070 maintain 2800 till established cleared for the arrival ILS 9. At that time I was completely set up for the approach and had reviewed the approach chart but was still unsure of my position in relation to wolff OM since as I had mentioned before jot VOR was OTS. Just as I was intercepting the localizer I thought I faintly heard the OM beacon but could not be sure because rain was pounding on the airplane making it difficult to hear. What had apparently happened was the controller had vectored me to intercept the localizer over wolff OM but with a wind at 3000 coming out of the southwest at 30 KTS and my airspeed of 110 IAS the intercept angle given placed me inside of wolff OM before localizer interception. At this point there were no flags on the ILS indicator and the GS needle should have indicated me high. While pondering this I didn't start timing because I was not sure I had passed wolff. I followed the GS with about a 300-400 FPM rate of descent even though I thought it odd that with such a high ground speed I would need something more like 750-800 FPM rate of descent. In any case, the GS needle stayed centered with no flags till I heard the MM at roughly 1300 MSL when the GS needle flag went red indicating the GS needle was unsafe to use. At this point I was thoroughly confused as to what was happening. I should have performed the missed approach procedure at this time but I believe denial set in saying that this could not be happening to me. At about 1200 MSL we broke out and I stayed at 1140 which is the MDA for the localizer (GS out) procedure while looking for the airport. Atthis time arrival tower called and said that chicago approach showed us east of the airport and had missed approach instructions for us. Being about 1-1 1/2 mi east of the airport (I knew that by my knowledge of the local area) I started to turn back toward the west (and the airport) and told tower to stand by. I felt this was the safest thing to do since if I had to do a missed approach I wanted to be going back toward the landing runway and I needed time to sort things out. Shortly after I turned wbound I caught sight of the airport and elected to land since I did not know if my navigation instruments were reliable and I had no VFR alternates within a safe distance. The landing was uneventful. Tower did ask me to call them and I was told chicago approach was going nuts because if they had had another plane coming down the ILS and had to miss the approach we could have collided by my coming back to the airport instead of flying the missed approach they were trying to give me when I was telling them to stand by. Tower ended the conversation by telling me to let this be a good lesson and not let it happen again. There were a number of mistakes and poor judgement going on here. With jot VOR OTS and being unsure of my position in relation to wolff OM I should have queried chicago approach as to my position. Secondly, when I suspected that the vector the controller gave me put me inside wolff OM before interception of the localizer I should have asked to be revectored since this initially put me high on the approach. Thirdly, I should have been suspicious about the GS needle when it was centered at a 300-400 FPM rate of descent when 700-800 FPM was required. Fourth, I did not put my self in the mindset that I would have to miss the approach which I normally do no matter what the WX. This caused me to debate at the MM as to whether I should continue the approach or not which in hindsight at the first few signs of trouble I should not have continued the approach. Fifth as to whether or not I should have flown back to the airport under the conditions of a ceiling at 1200 MSL and a visibility of 1 1/2-2MI. I believe that I did the correct thing since I knew where I was and I did not relish the thought of losing my navigation instruments with no good VFR alternates within a few hundred mi. I understand the tower's concern over the possibility of a collision with another airplane but with our problems and the navigation instrument problems I believe I took the safest course of action. The WX was rapidly deteriorating in the area and that also led to my decision to go back towards the airport. Finally, as to the question about what happened with the GS needle. Previously (45 mins) I had completed an approach into rfd ILS 36 with no problem with the GS needle. The shop is still investigating the problem with the GS needle. The only other explanation I can think of is there were 2 other airplanes waiting to takeoff from runway 27 and were right up against the ILS hold lines. These lines appear to be very close to the runway compared to ILS hold lines at other airports. Additionally, there was also another airplane on the approach before us and interestingly enough he had to perform a missed approach (for what reason I do not know). Callback conversation with reporter revealed the following information: reporter said he had received ATIS and surface winds were such that he had planned a straight in approach to runway 9. There was traffic following him which may explain why approach controller was hurrying him. He was cleared for a straight in approach.

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Original NASA ASRS Text

Title: SMA SHOOTS ILS APCH, IS ABOVE GS AND BREAKS OUT BEYOND THE ARPT. HE THEN FLIES A CIRCLING APCH THAT HE HAS NOT BEEN CLRED TO DO.

Narrative: I WAS BEING VECTORED ONTO THE ARR ILS 9 APCH. CHICAGO APCH VECTORED ME ACROSS THE FINAL APCH COURSE FROM N TO S. SINCE THE APCH DOES NOT HAVE DME AND THE JOT VOR WAS OTS I WAS HAVING PROBLEMS DETERMINING MY POS IN RELATION TO THE OM WOLFF. AFTER PASSING THROUGH THE FINAL APCH COURSE ON A HDG OF 180 DEGS I WAS THEN TOLD TO TURN TO R TO A HDG OF 070 DEGS AND DSND AND MAINTAIN 3000 (I HAD BEEN AT 4000). SHORTLY AFTER I HAD COMPLETED THE TURN CHICAGO APCH TOLD ME HDG 070 MAINTAIN 2800 TILL ESTABLISHED CLRED FOR THE ARR ILS 9. AT THAT TIME I WAS COMPLETELY SET UP FOR THE APCH AND HAD REVIEWED THE APCH CHART BUT WAS STILL UNSURE OF MY POS IN RELATION TO WOLFF OM SINCE AS I HAD MENTIONED BEFORE JOT VOR WAS OTS. JUST AS I WAS INTERCEPTING THE LOC I THOUGHT I FAINTLY HEARD THE OM BEACON BUT COULD NOT BE SURE BECAUSE RAIN WAS POUNDING ON THE AIRPLANE MAKING IT DIFFICULT TO HEAR. WHAT HAD APPARENTLY HAPPENED WAS THE CTLR HAD VECTORED ME TO INTERCEPT THE LOC OVER WOLFF OM BUT WITH A WIND AT 3000 COMING OUT OF THE SW AT 30 KTS AND MY AIRSPD OF 110 IAS THE INTERCEPT ANGLE GIVEN PLACED ME INSIDE OF WOLFF OM BEFORE LOC INTERCEPTION. AT THIS POINT THERE WERE NO FLAGS ON THE ILS INDICATOR AND THE GS NEEDLE SHOULD HAVE INDICATED ME HIGH. WHILE PONDERING THIS I DIDN'T START TIMING BECAUSE I WAS NOT SURE I HAD PASSED WOLFF. I FOLLOWED THE GS WITH ABOUT A 300-400 FPM RATE OF DSCNT EVEN THOUGH I THOUGHT IT ODD THAT WITH SUCH A HIGH GND SPD I WOULD NEED SOMETHING MORE LIKE 750-800 FPM RATE OF DSCNT. IN ANY CASE, THE GS NEEDLE STAYED CENTERED WITH NO FLAGS TILL I HEARD THE MM AT ROUGHLY 1300 MSL WHEN THE GS NEEDLE FLAG WENT RED INDICATING THE GS NEEDLE WAS UNSAFE TO USE. AT THIS POINT I WAS THOROUGHLY CONFUSED AS TO WHAT WAS HAPPENING. I SHOULD HAVE PERFORMED THE MISSED APCH PROC AT THIS TIME BUT I BELIEVE DENIAL SET IN SAYING THAT THIS COULD NOT BE HAPPENING TO ME. AT ABOUT 1200 MSL WE BROKE OUT AND I STAYED AT 1140 WHICH IS THE MDA FOR THE LOC (GS OUT) PROC WHILE LOOKING FOR THE ARPT. ATTHIS TIME ARR TWR CALLED AND SAID THAT CHICAGO APCH SHOWED US E OF THE ARPT AND HAD MISSED APCH INSTRUCTIONS FOR US. BEING ABOUT 1-1 1/2 MI E OF THE ARPT (I KNEW THAT BY MY KNOWLEDGE OF THE LCL AREA) I STARTED TO TURN BACK TOWARD THE W (AND THE ARPT) AND TOLD TWR TO STAND BY. I FELT THIS WAS THE SAFEST THING TO DO SINCE IF I HAD TO DO A MISSED APCH I WANTED TO BE GOING BACK TOWARD THE LNDG RWY AND I NEEDED TIME TO SORT THINGS OUT. SHORTLY AFTER I TURNED WBOUND I CAUGHT SIGHT OF THE ARPT AND ELECTED TO LAND SINCE I DID NOT KNOW IF MY NAV INSTS WERE RELIABLE AND I HAD NO VFR ALTERNATES WITHIN A SAFE DISTANCE. THE LNDG WAS UNEVENTFUL. TWR DID ASK ME TO CALL THEM AND I WAS TOLD CHICAGO APCH WAS GOING NUTS BECAUSE IF THEY HAD HAD ANOTHER PLANE COMING DOWN THE ILS AND HAD TO MISS THE APCH WE COULD HAVE COLLIDED BY MY COMING BACK TO THE ARPT INSTEAD OF FLYING THE MISSED APCH THEY WERE TRYING TO GIVE ME WHEN I WAS TELLING THEM TO STAND BY. TWR ENDED THE CONVERSATION BY TELLING ME TO LET THIS BE A GOOD LESSON AND NOT LET IT HAPPEN AGAIN. THERE WERE A NUMBER OF MISTAKES AND POOR JUDGEMENT GOING ON HERE. WITH JOT VOR OTS AND BEING UNSURE OF MY POS IN RELATION TO WOLFF OM I SHOULD HAVE QUERIED CHICAGO APCH AS TO MY POS. SECONDLY, WHEN I SUSPECTED THAT THE VECTOR THE CTLR GAVE ME PUT ME INSIDE WOLFF OM BEFORE INTERCEPTION OF THE LOC I SHOULD HAVE ASKED TO BE REVECTORED SINCE THIS INITIALLY PUT ME HIGH ON THE APCH. THIRDLY, I SHOULD HAVE BEEN SUSPICIOUS ABOUT THE GS NEEDLE WHEN IT WAS CENTERED AT A 300-400 FPM RATE OF DSCNT WHEN 700-800 FPM WAS REQUIRED. FOURTH, I DID NOT PUT MY SELF IN THE MINDSET THAT I WOULD HAVE TO MISS THE APCH WHICH I NORMALLY DO NO MATTER WHAT THE WX. THIS CAUSED ME TO DEBATE AT THE MM AS TO WHETHER I SHOULD CONTINUE THE APCH OR NOT WHICH IN HINDSIGHT AT THE FIRST FEW SIGNS OF TROUBLE I SHOULD NOT HAVE CONTINUED THE APCH. FIFTH AS TO WHETHER OR NOT I SHOULD HAVE FLOWN BACK TO THE ARPT UNDER THE CONDITIONS OF A CEILING AT 1200 MSL AND A VISIBILITY OF 1 1/2-2MI. I BELIEVE THAT I DID THE CORRECT THING SINCE I KNEW WHERE I WAS AND I DID NOT RELISH THE THOUGHT OF LOSING MY NAV INSTS WITH NO GOOD VFR ALTERNATES WITHIN A FEW HUNDRED MI. I UNDERSTAND THE TWR'S CONCERN OVER THE POSSIBILITY OF A COLLISION WITH ANOTHER AIRPLANE BUT WITH OUR PROBLEMS AND THE NAV INST PROBLEMS I BELIEVE I TOOK THE SAFEST COURSE OF ACTION. THE WX WAS RAPIDLY DETERIORATING IN THE AREA AND THAT ALSO LED TO MY DECISION TO GO BACK TOWARDS THE ARPT. FINALLY, AS TO THE QUESTION ABOUT WHAT HAPPENED WITH THE GS NEEDLE. PREVIOUSLY (45 MINS) I HAD COMPLETED AN APCH INTO RFD ILS 36 WITH NO PROBLEM WITH THE GS NEEDLE. THE SHOP IS STILL INVESTIGATING THE PROBLEM WITH THE GS NEEDLE. THE ONLY OTHER EXPLANATION I CAN THINK OF IS THERE WERE 2 OTHER AIRPLANES WAITING TO TKOF FROM RWY 27 AND WERE RIGHT UP AGAINST THE ILS HOLD LINES. THESE LINES APPEAR TO BE VERY CLOSE TO THE RWY COMPARED TO ILS HOLD LINES AT OTHER ARPTS. ADDITIONALLY, THERE WAS ALSO ANOTHER AIRPLANE ON THE APCH BEFORE US AND INTERESTINGLY ENOUGH HE HAD TO PERFORM A MISSED APCH (FOR WHAT REASON I DO NOT KNOW). CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR SAID HE HAD RECEIVED ATIS AND SURFACE WINDS WERE SUCH THAT HE HAD PLANNED A STRAIGHT IN APCH TO RWY 9. THERE WAS TFC FOLLOWING HIM WHICH MAY EXPLAIN WHY APCH CTLR WAS HURRYING HIM. HE WAS CLRED FOR A STRAIGHT IN 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.