Departing orh, PA31 pilot has an altitude deviation due to an incorrect altimeter setting.

Attributes
ACN	601049
Time
Date	200311
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : orh.airport
State Reference	MA
Altitude	msl single value : 5000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : y90.tracon
Operator	general aviation : corporate
Make Model Name	PA-31 Navajo Chieftan/Mojave/Navajo T1020
Flight Phase	climbout : intermediate altitude ground : parked
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : single pilot
Qualification	pilot : atp pilot : instrument pilot : multi engine pilot : commercial
ASRS Report	601049
Person 2
Affiliation	government : faa
Function	controller : approach
Events
Anomaly	altitude deviation : overshoot non adherence : clearance non adherence : published procedure
Independent Detector	atc equipment other atc equipment : radar other controllera
Resolutory Action	controller : issued new clearance controller : issued advisory
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was flying alone (usually we fly with 2 pilots) this day. I decided to go IFR even though it was VFR. I intentionally took my time with all phases of the flight and used the checklist. The flight was to pick up passenger. My takeoff clearance was for runway 29, climb to 2000 ft and a left turn to 240 degrees. I took off and was handed off to bradley approach. I reported at about 1200 ft. Bradley asked for an identify and cleared me to 4000 ft. I do not recall a 'radar contact' and/or an altitude confirmation. It may have been given, but it was very turbulent. Bradley called and said 'maintain 4000 ft.' I replied 'maintain 4000 ft.' bradley then informed me that I was at 4900 ft and asked my altitude. I said I was leveling at 4000 ft. Bradley said I was at 5000 ft. I checked the other altimeter and it read 5000 ft. I confirmed that I was at 5000 ft and bradley said it was ok, just stay at 5000 ft. It was then I realized I set the wrong altimeter setting in the left side altimeter before takeoff. I don't know how I could have made such a mistake. I have never had anything like this happen in my many yrs of flying. I know it will never happen again just because of its very nature. 'A really dumb mistake.'

Original NASA ASRS Text

Title: DEPARTING ORH, PA31 PLT HAS AN ALTDEV DUE TO AN INCORRECT ALTIMETER SETTING.

Narrative: I WAS FLYING ALONE (USUALLY WE FLY WITH 2 PLTS) THIS DAY. I DECIDED TO GO IFR EVEN THOUGH IT WAS VFR. I INTENTIONALLY TOOK MY TIME WITH ALL PHASES OF THE FLT AND USED THE CHKLIST. THE FLT WAS TO PICK UP PAX. MY TKOF CLRNC WAS FOR RWY 29, CLB TO 2000 FT AND A L TURN TO 240 DEGS. I TOOK OFF AND WAS HANDED OFF TO BRADLEY APCH. I RPTED AT ABOUT 1200 FT. BRADLEY ASKED FOR AN IDENT AND CLRED ME TO 4000 FT. I DO NOT RECALL A 'RADAR CONTACT' AND/OR AN ALT CONFIRMATION. IT MAY HAVE BEEN GIVEN, BUT IT WAS VERY TURBULENT. BRADLEY CALLED AND SAID 'MAINTAIN 4000 FT.' I REPLIED 'MAINTAIN 4000 FT.' BRADLEY THEN INFORMED ME THAT I WAS AT 4900 FT AND ASKED MY ALT. I SAID I WAS LEVELING AT 4000 FT. BRADLEY SAID I WAS AT 5000 FT. I CHKED THE OTHER ALTIMETER AND IT READ 5000 FT. I CONFIRMED THAT I WAS AT 5000 FT AND BRADLEY SAID IT WAS OK, JUST STAY AT 5000 FT. IT WAS THEN I REALIZED I SET THE WRONG ALTIMETER SETTING IN THE L SIDE ALTIMETER BEFORE TKOF. I DON'T KNOW HOW I COULD HAVE MADE SUCH A MISTAKE. I HAVE NEVER HAD ANYTHING LIKE THIS HAPPEN IN MY MANY YRS OF FLYING. I KNOW IT WILL NEVER HAPPEN AGAIN JUST BECAUSE OF ITS VERY NATURE. 'A REALLY DUMB MISTAKE.'

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.