Narrative:

On the takeoff roll out of avp my first officer was giving me standard calls. At V1 I started to rotate, and looked inside only to notice that I had 0 airspeed. I cross checked to the first officer's airspeed which was approaching 125 KTS and continued the rotation. At approximately 100' AGL I informed the first officer that he was flying and we returned for landing west/O incident. I then notified maintenance by telephone. I was instructed to get a ground power unit, and turn on the pitot heat. After 10 mins I was to do a high speed taxi to check system. I did as instructed, the aircraft worked fine, and I returned, reboarded the flight and continued to baltimore. After talking with other pilots at baltimore I realized that I was in violation of far 1z5.65 by not writing up the problem and having it properly cleared by maintenance. This action would have grounded the aircraft as the captain's airspeed indicator cannot be MEL'd. Callback conversation with reporter revealed the following: this was the third leg of day for this crew with this aircraft and on the inbound they had flown through moisture and then had been on the ground for an extended period where the temperature was very cold. Apparently water in captain's pitot froze while on ground and pitot heater did not have time to thaw it out before takeoff. PIC had not realized any time incident like this discrepancy occurred it had to be entered in aircraft log book and signed off by a&P.

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Original NASA ASRS Text

Title: AT ROTATE ACR LTT PF NOTICED AIRSPEED INDICATOR INOPERATIVE. CONTINUED TKOF, PASSED FLYING DUTIES TO FO WHOSE INDICATOR WAS OK AND RETURNED AND LANDED.

Narrative: ON THE TKOF ROLL OUT OF AVP MY F/O WAS GIVING ME STANDARD CALLS. AT V1 I STARTED TO ROTATE, AND LOOKED INSIDE ONLY TO NOTICE THAT I HAD 0 AIRSPD. I CROSS CHKED TO THE F/O'S AIRSPD WHICH WAS APCHING 125 KTS AND CONTINUED THE ROTATION. AT APPROX 100' AGL I INFORMED THE F/O THAT HE WAS FLYING AND WE RETURNED FOR LNDG W/O INCIDENT. I THEN NOTIFIED MAINT BY TELEPHONE. I WAS INSTRUCTED TO GET A GND PWR UNIT, AND TURN ON THE PITOT HEAT. AFTER 10 MINS I WAS TO DO A HIGH SPD TAXI TO CHK SYS. I DID AS INSTRUCTED, THE ACFT WORKED FINE, AND I RETURNED, REBOARDED THE FLT AND CONTINUED TO BALTIMORE. AFTER TALKING WITH OTHER PLTS AT BALTIMORE I REALIZED THAT I WAS IN VIOLATION OF FAR 1Z5.65 BY NOT WRITING UP THE PROB AND HAVING IT PROPERLY CLRED BY MAINT. THIS ACTION WOULD HAVE GNDED THE ACFT AS THE CAPT'S AIRSPD INDICATOR CANNOT BE MEL'D. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: THIS WAS THE THIRD LEG OF DAY FOR THIS CREW WITH THIS ACFT AND ON THE INBND THEY HAD FLOWN THROUGH MOISTURE AND THEN HAD BEEN ON THE GND FOR AN EXTENDED PERIOD WHERE THE TEMP WAS VERY COLD. APPARENTLY WATER IN CAPT'S PITOT FROZE WHILE ON GND AND PITOT HEATER DID NOT HAVE TIME TO THAW IT OUT BEFORE TKOF. PIC HAD NOT REALIZED ANY TIME INCIDENT LIKE THIS DISCREPANCY OCCURRED IT HAD TO BE ENTERED IN ACFT LOG BOOK AND SIGNED OFF BY A&P.

Data retrieved from NASA's ASRS site as of August 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.