Narrative:

I took off from ugn on a routine (much traveled) trip to dkb. The course was southwest and dictates that you must fly under the TCA (below 3600' MSL) until you are beyond 25 NM from ugn. My intentions were to climb to 3400' MSL (arrive) at or beyond the 25 NM range. I departed the ugn air traffic area at 2000' MSL trimmed to a climb rate of about 80 FPM and settled in. Approximately 16 NM from ugn (at 3500' MSL) I began to experience invalid ADF readings. I began to check the instrument and also utilize the VOR for reference. In the process I was unable to maintain ground reference due to a layer of haze. When I next checked my altimeter, I was at 4300' MSL. I knew I was not out of TCA range and immediately began a descent to 2900' MSL for the duration of the flight. There were no aircraft in the area, so I didn't contributed to a safety situation. What caused the problem was my confidence that I didn't have to worry about any significant altitude changes even though I was only 300' below the TCA. To prevent a recurrence I (or anyone else) merely need to reinforce the attitude/discipline that when you are that close to the limit, pay more attention to the situation at hand. Altitude management is and always will be critical. I thought I was better than I was. The area, altitudes, references were not strange to me. I went through the same preflight prep this time as always.

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Original NASA ASRS Text

Title: PVT PLT CHECKING ACFT EQUIPMENT CLIMBS INTO TCA.

Narrative: I TOOK OFF FROM UGN ON A ROUTINE (MUCH TRAVELED) TRIP TO DKB. THE COURSE WAS SW AND DICTATES THAT YOU MUST FLY UNDER THE TCA (BELOW 3600' MSL) UNTIL YOU ARE BEYOND 25 NM FROM UGN. MY INTENTIONS WERE TO CLB TO 3400' MSL (ARRIVE) AT OR BEYOND THE 25 NM RANGE. I DEPARTED THE UGN ATA AT 2000' MSL TRIMMED TO A CLB RATE OF ABOUT 80 FPM AND SETTLED IN. APPROX 16 NM FROM UGN (AT 3500' MSL) I BEGAN TO EXPERIENCE INVALID ADF READINGS. I BEGAN TO CHK THE INSTRUMENT AND ALSO UTILIZE THE VOR FOR REF. IN THE PROCESS I WAS UNABLE TO MAINTAIN GND REF DUE TO A LAYER OF HAZE. WHEN I NEXT CHKED MY ALTIMETER, I WAS AT 4300' MSL. I KNEW I WAS NOT OUT OF TCA RANGE AND IMMEDIATELY BEGAN A DSNT TO 2900' MSL FOR THE DURATION OF THE FLT. THERE WERE NO ACFT IN THE AREA, SO I DIDN'T CONTRIBUTED TO A SAFETY SITUATION. WHAT CAUSED THE PROB WAS MY CONFIDENCE THAT I DIDN'T HAVE TO WORRY ABOUT ANY SIGNIFICANT ALT CHANGES EVEN THOUGH I WAS ONLY 300' BELOW THE TCA. TO PREVENT A RECURRENCE I (OR ANYONE ELSE) MERELY NEED TO REINFORCE THE ATTITUDE/DISCIPLINE THAT WHEN YOU ARE THAT CLOSE TO THE LIMIT, PAY MORE ATTN TO THE SITUATION AT HAND. ALT MGMNT IS AND ALWAYS WILL BE CRITICAL. I THOUGHT I WAS BETTER THAN I WAS. THE AREA, ALTS, REFS WERE NOT STRANGE TO ME. I WENT THROUGH THE SAME PREFLT PREP THIS TIME AS ALWAYS.

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.