Narrative:

I incorrectly set altimeter to 30.61 instead of correct setting 29.61 at beginning of flight. I checked the field elevation with long altimeter needle (steam gauges) and verified what appeared to be the right field elevation; not realizing the 1;000 foot off error. On initial climbout and departure; I checked in with '...runway heading; 2;700 climbing 3;000 ft'. I felt that I reached 2;700 more quickly than normal; but attributed it to being a cool night with only myself in the airplane. The departure controller acknowledged; but did not catch the altitude discrepancy. I leveled off when my altimeter indicated 3;000 ft and remained on my assigned heading. It was at this point that the visible terrain was going by much faster than I expected. I started suspecting I was too low; but then the departure controller came back with '...sorry; for traffic I need to keep you at 2;500 ft; descend and maintain 2;500 ft.' at this point I second guessed my feelings and started a descent to 2;500 ft; but stopped and leveled off when my altimeter [indicated] approximately 2;700 ft due to being further uncomfortable with my proximity to the ground. While trying to figure out why ATC would give me such a 'low altitude'; I switched to terrain view on the GNS430 unit in the plane and noticed a full screen of yellow terrain; with some obstacles ahead of me turning red. At this point I decided that the situation was unsafe; and decided to deviate from what I thought was the ATC assigned altitude and started a full power climb. A few seconds later I received an obstacle alert on the GNS430 along with the ATC controller issuing an urgent altitude alert with recommendation to climb. At this point I realized my altimeter mistake. I had only heard an altitude alert issued once before; on post-crash analysis tapes of a fatal baron accident in our local area. To say I was freaked out about the close call would be an understatement. Shortly thereafter I was given vectors for the ILS and entered an IMC overcast layer at roughly 2;100 ft. I had not expected an IMC overcast based on a metar reporting a broken layer at 600 ft and nothing else up to 7;000 or 8;000 ft. I started to second guess everything about my approach setup; what the instruments were telling me; and quickly realized I was not in a mental state to do an ILS approach in IMC. I started thinking more about the close call and things that could still go wrong than focusing on the approach. I wanted to buy some time and climb to 5;000 ft and collect myself; but did not due to fear of further angering an already irritated ATC controller (again; my mistake; should not have let ATC's tone influence my decisions). I had seen the ceiling before entering the IMC layer and knew I had VFR conditions a few hundred feet below. ATC had assigned 2;500 ft for the initial localizer fix. I further made mistakes by trying to identification the fix using my navigation 2 audio selector when the localizer was tuned to navigation 1. My mental capacity decreased to the point where I lost situational awareness as to where I was on the approach; my position relative to the airport; and was not comprehending what the moving map was telling me. I flew through the localizer course twice; and ATC offered vectors for a missed approach. At this point I experienced a brief break in the clouds and saw the runway lights. I could see another layer coming up in less than a half mile; so again decided that my mental state was too dangerous for IMC when a better option presented itself; and again decided to deviate from assigned altitude and descended well below the glideslope and just below the cloud layer; and cross checked with terrain view on the GNS430 to make sure there were no obstacle or terrain concerns. The thought of a going missed and re-entering IMC was the last option I wanted to take. I advised ATC that I had the runway in sight; and would be proceeding visually. ATC responded with 'the field is still technically IFR so I cannot clear you forthat approach.' at this point; in hindsight; I should have declared my intent to deviate due to an emergency; but instead just told ATC I had the localizer so they would pass me off to the tower for landing clearance. At this point; the ATC controller cleared me for the approach; and I landed visually. The tower informed me to call approach by phone when able. I called approach; and a different controller expressed concern for the altitude alert; wanted to know what happened; and wanted to make sure I was okay. The initial incident seemed to result from a chain of events; starting with my error; continuing with departure not realizing the altitude discrepancy on check-in; and continuing with a very decreased mental capacity after experiencing the altitude alert.

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Original NASA ASRS Text

Title: The pilot of a Piper PA32 began a flight with a one thousand foot error in the altimeter setting which led to a low altitude warning. After climbing; and recognizing the altimeter setting error; the pilot's stress level made it difficult for him to perform an ILS approach. He elected to descend below the glideslope when he observed a break in the cloud layer; and landed safely.

Narrative: I incorrectly set altimeter to 30.61 instead of correct setting 29.61 at beginning of flight. I checked the field elevation with long altimeter needle (steam gauges) and verified what appeared to be the right field elevation; not realizing the 1;000 foot off error. On initial climbout and departure; I checked in with '...runway heading; 2;700 climbing 3;000 FT'. I felt that I reached 2;700 more quickly than normal; but attributed it to being a cool night with only myself in the airplane. The Departure Controller acknowledged; but did not catch the altitude discrepancy. I leveled off when my altimeter indicated 3;000 FT and remained on my assigned heading. It was at this point that the visible terrain was going by much faster than I expected. I started suspecting I was too low; but then the Departure Controller came back with '...sorry; for traffic I need to keep you at 2;500 FT; descend and maintain 2;500 FT.' At this point I second guessed my feelings and started a descent to 2;500 FT; but stopped and leveled off when my altimeter [indicated] approximately 2;700 FT due to being further uncomfortable with my proximity to the ground. While trying to figure out why ATC would give me such a 'low altitude'; I switched to Terrain View on the GNS430 unit in the plane and noticed a full screen of yellow terrain; with some obstacles ahead of me turning red. At this point I decided that the situation was unsafe; and decided to deviate from what I thought was the ATC assigned altitude and started a full power climb. A few seconds later I received an obstacle alert on the GNS430 along with the ATC Controller issuing an urgent altitude alert with recommendation to climb. At this point I realized my altimeter mistake. I had only heard an altitude alert issued once before; on post-crash analysis tapes of a fatal Baron accident in our local area. To say I was freaked out about the close call would be an understatement. Shortly thereafter I was given vectors for the ILS and entered an IMC overcast layer at roughly 2;100 FT. I had not expected an IMC overcast based on a METAR reporting a broken layer at 600 FT and nothing else up to 7;000 or 8;000 FT. I started to second guess everything about my approach setup; what the instruments were telling me; and quickly realized I was not in a mental state to do an ILS approach in IMC. I started thinking more about the close call and things that could still go wrong than focusing on the approach. I wanted to buy some time and climb to 5;000 FT and collect myself; but did not due to fear of further angering an already irritated ATC Controller (again; my mistake; should not have let ATC's tone influence my decisions). I had seen the ceiling before entering the IMC layer and knew I had VFR conditions a few hundred feet below. ATC had assigned 2;500 FT for the initial localizer fix. I further made mistakes by trying to ID the fix using my NAV 2 audio selector when the localizer was tuned to NAV 1. My mental capacity decreased to the point where I lost situational awareness as to where I was on the approach; my position relative to the airport; and was not comprehending what the moving map was telling me. I flew through the localizer course twice; and ATC offered vectors for a missed approach. At this point I experienced a brief break in the clouds and saw the runway lights. I could see another layer coming up in less than a half mile; so again decided that my mental state was too dangerous for IMC when a better option presented itself; and again decided to deviate from assigned altitude and descended well below the glideslope and just below the cloud layer; and cross checked with terrain view on the GNS430 to make sure there were no obstacle or terrain concerns. The thought of a going missed and re-entering IMC was the last option I wanted to take. I advised ATC that I had the runway in sight; and would be proceeding visually. ATC responded with 'the field is still technically IFR so I cannot clear you forthat approach.' At this point; in hindsight; I should have declared my intent to deviate due to an emergency; but instead just told ATC I had the localizer so they would pass me off to the Tower for landing clearance. At this point; the ATC Controller cleared me for the approach; and I landed visually. The Tower informed me to call Approach by phone when able. I called Approach; and a different controller expressed concern for the altitude alert; wanted to know what happened; and wanted to make sure I was okay. The initial incident seemed to result from a chain of events; starting with my error; continuing with departure not realizing the altitude discrepancy on check-in; and continuing with a very decreased mental capacity after experiencing the altitude alert.

Data retrieved from NASA's ASRS site 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.