Narrative:

I was on an IFR flight plan from opf to dca in a heavy, IMC at altitude of 11000 ft at about 40 mi south of rdu. I noticed that my airspeed indicator that usually gives a reading of about 150 KTS, gave a reading of 125 KTS. Prior to entering IMC I turn on all de-ice and anti-ice equipment. Upon entering IMC I noticed that the airspeed began to decrease. I crosschecked my power and my pitch and they seemed to be normal with the exception of my airspeed indicator. I suspected ice accumulation in the pitot tube. I then requested lower altitude from ZDC. Air data computer denied my request for descent and informed me that it will take a few mins due to heavy traffic. At that time, I noticed my airspeed decrease to 90 KTS, I then called ZDC and informed that I need an immediate descent. They asked me if I would like to declare emergency which I did. They cleared me to 8000 ft and heading change of 90 degrees to the right (080 degrees), at 8000 ft I was still IMC so they cleared me to 6000 ft to VMC conditions. Throughout the descent my airspeed indicated 0 KTS. I was vectored to rdu where I made normal landing on runway 23L. An inspection on the ground at rdu discovered a loose wire in the pitot tube heating element. The technician fixed the wiring and the problem was solved. The aircraft was recently (2 weeks prior to this incident) purchased and went through pre-purchase inspection. I suspect that removal of the pitot mast caused the wires to come loose.

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Original NASA ASRS Text

Title: SMA ENCOUNTERS ICING, UNABLE TO SUSTAIN ALT. REQUESTED LOWER, UNABLE, DECLARES EMER. MAKES EMER LNDG AT RDU.

Narrative: I WAS ON AN IFR FLT PLAN FROM OPF TO DCA IN A HVY, IMC AT ALT OF 11000 FT AT ABOUT 40 MI S OF RDU. I NOTICED THAT MY AIRSPD INDICATOR THAT USUALLY GIVES A READING OF ABOUT 150 KTS, GAVE A READING OF 125 KTS. PRIOR TO ENTERING IMC I TURN ON ALL DE-ICE AND ANTI-ICE EQUIP. UPON ENTERING IMC I NOTICED THAT THE AIRSPD BEGAN TO DECREASE. I XCHKED MY PWR AND MY PITCH AND THEY SEEMED TO BE NORMAL WITH THE EXCEPTION OF MY AIRSPD INDICATOR. I SUSPECTED ICE ACCUMULATION IN THE PITOT TUBE. I THEN REQUESTED LOWER ALT FROM ZDC. ADC DENIED MY REQUEST FOR DSCNT AND INFORMED ME THAT IT WILL TAKE A FEW MINS DUE TO HVY TFC. AT THAT TIME, I NOTICED MY AIRSPD DECREASE TO 90 KTS, I THEN CALLED ZDC AND INFORMED THAT I NEED AN IMMEDIATE DSCNT. THEY ASKED ME IF I WOULD LIKE TO DECLARE EMER WHICH I DID. THEY CLRED ME TO 8000 FT AND HDG CHANGE OF 90 DEGS TO THE R (080 DEGS), AT 8000 FT I WAS STILL IMC SO THEY CLRED ME TO 6000 FT TO VMC CONDITIONS. THROUGHOUT THE DSCNT MY AIRSPD INDICATED 0 KTS. I WAS VECTORED TO RDU WHERE I MADE NORMAL LNDG ON RWY 23L. AN INSPECTION ON THE GND AT RDU DISCOVERED A LOOSE WIRE IN THE PITOT TUBE HEATING ELEMENT. THE TECHNICIAN FIXED THE WIRING AND THE PROBLEM WAS SOLVED. THE ACFT WAS RECENTLY (2 WKS PRIOR TO THIS INCIDENT) PURCHASED AND WENT THROUGH PRE-PURCHASE INSPECTION. I SUSPECT THAT REMOVAL OF THE PITOT MAST CAUSED THE WIRES TO COME LOOSE.

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.