Narrative:

Route of flight was planned: depart bed, climb 2300 ft en route owd, nzw, 3b2 destination. Had departed bed, picked up owd ATIS, contacted owd for permission transit class D, received, misread altimeter, was passing 3200 ft, immediately descended 2300 ft, approximately 7 mi north of owd. Not clear if this was a class B penetration, I was right on the 'ring' which separated floor of 3000 ft from 4000 ft. But the misread of altitude still bothers me a lot. Retrospect, 1) first hot day in boston, beginning of a 3 day heat wave, 2) I was fatigued from work, 3) dehydrated, 4) aircraft was climbing slowly. Way to prevent: don't fly under conditions (fatigue, dehydration) as noted above. Was also fairly clear, gives one illusion of being lower than one actually is.

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Original NASA ASRS Text

Title: SMA PLT CLBS ABOVE HIS PLANNED VFR CRUISE ALT AND ENTERS THE RING OF THE 3000 FT BASE OF THE BOS CLASS B AIRSPACE. RPTR WAS FATIGUED AND DEHYDRATED.

Narrative: RTE OF FLT WAS PLANNED: DEPART BED, CLB 2300 FT ENRTE OWD, NZW, 3B2 DEST. HAD DEPARTED BED, PICKED UP OWD ATIS, CONTACTED OWD FOR PERMISSION TRANSIT CLASS D, RECEIVED, MISREAD ALTIMETER, WAS PASSING 3200 FT, IMMEDIATELY DSNDED 2300 FT, APPROX 7 MI N OF OWD. NOT CLR IF THIS WAS A CLASS B PENETRATION, I WAS R ON THE 'RING' WHICH SEPARATED FLOOR OF 3000 FT FROM 4000 FT. BUT THE MISREAD OF ALT STILL BOTHERS ME A LOT. RETROSPECT, 1) FIRST HOT DAY IN BOSTON, BEGINNING OF A 3 DAY HEAT WAVE, 2) I WAS FATIGUED FROM WORK, 3) DEHYDRATED, 4) ACFT WAS CLBING SLOWLY. WAY TO PREVENT: DON'T FLY UNDER CONDITIONS (FATIGUE, DEHYDRATION) AS NOTED ABOVE. WAS ALSO FAIRLY CLR, GIVES ONE ILLUSION OF BEING LOWER THAN ONE ACTUALLY IS.

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.