Narrative:

We were instructed to turn left to 090 and climb and maintain 3000. Upon reaching 3000 departure informed us we were at 3300 ft. In the meridian there are three drains on the pilot side and two drains on the co-pilot side near the floor. These must be drained before every flight on the ground. In doing so a foreign object entered one or more of the drains. As we pressurized; it caused an error of 180 ft+/-;and a 40KT+/- error in IAS. We used the stand-by altimeter to continue the flight. We took the aircraft to a maintenance facility who corrected the problem. I don't know how to prevent this; the service center said it is a problem with some meridians. I suppose it is piper's problem. I am just glad there is a stand-by system.

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Original NASA ASRS Text

Title: A PA46T pilot reported erroneous airspeed and altimeter readings apparently caused by a foreign object in the pitot drain.

Narrative: We were instructed to turn left to 090 and climb and maintain 3000. Upon reaching 3000 Departure informed us we were at 3300 FT. In the Meridian there are three drains on the pilot side and two drains on the co-pilot side near the floor. These must be drained before every flight on the ground. In doing so a foreign object entered one or more of the drains. As we pressurized; it caused an error of 180 FT+/-;and a 40KT+/- error in IAS. We used the stand-by altimeter to continue the flight. We took the aircraft to a maintenance facility who corrected the problem. I don't know how to prevent this; the service center said it is a problem with some Meridians. I suppose it is Piper's problem. I am just glad there is a stand-by system.

Data retrieved from NASA's ASRS site as of April 2012 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.