Narrative:

After a normal rotation and initial climb, the first officer's airspeed indicator stuck at approximately 140 KTS, while the captain's airspeed indicator accelerated. In compliance with company policies and procedures, the appropriate checklists were accomplished. I declared an emergency and after briefing the flight crew and passengers, returned to the field with a normal landing and rollout. After taxiing to the gate, a logbook entry was made where maintenance personnel investigated the problem. This was the first flight of the day for this particular aircraft. It had come from the maintenance hangar where maintenance was performed in areas not related to our problem. Although a thorough preflight inspection was performed inside and out, it seems that once an aircraft is given to the flcs, it is rarely returned with the switches, cbs, etc in the normal positions. Perhaps in this case, there may have been some foreign material ingested in the pitot system that to the naked eye was undetectable. A solution to this type of situation may be to use extra care when performing maintenance (using proper covers) and return all cbs, handles, switches etc, to the normal positions before returning the aircraft to flight line status in an effort to enhance safety and safeguard against overlooking what could be the obvious.

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Original NASA ASRS Text

Title: FO AIRSPEED INDICATOR FAILED. FLT RETURNED LANDED.

Narrative: AFTER A NORMAL ROTATION AND INITIAL CLB, THE FO'S AIRSPD INDICATOR STUCK AT APPROX 140 KTS, WHILE THE CAPT'S AIRSPD INDICATOR ACCELERATED. IN COMPLIANCE WITH COMPANY POLICIES AND PROCS, THE APPROPRIATE CHKLISTS WERE ACCOMPLISHED. I DECLARED AN EMER AND AFTER BRIEFING THE FLC AND PAXS, RETURNED TO THE FIELD WITH A NORMAL LNDG AND ROLLOUT. AFTER TAXIING TO THE GATE, A LOGBOOK ENTRY WAS MADE WHERE MAINT PERSONNEL INVESTIGATED THE PROB. THIS WAS THE FIRST FLT OF THE DAY FOR THIS PARTICULAR ACFT. IT HAD COME FROM THE MAINT HANGAR WHERE MAINT WAS PERFORMED IN AREAS NOT RELATED TO OUR PROB. ALTHOUGH A THOROUGH PREFLT INSPECTION WAS PERFORMED INSIDE AND OUT, IT SEEMS THAT ONCE AN ACFT IS GIVEN TO THE FLCS, IT IS RARELY RETURNED WITH THE SWITCHES, CBS, ETC IN THE NORMAL POSITIONS. PERHAPS IN THIS CASE, THERE MAY HAVE BEEN SOME FOREIGN MATERIAL INGESTED IN THE PITOT SYS THAT TO THE NAKED EYE WAS UNDETECTABLE. A SOLUTION TO THIS TYPE OF SIT MAY BE TO USE EXTRA CARE WHEN PERFORMING MAINT (USING PROPER COVERS) AND RETURN ALL CBS, HANDLES, SWITCHES ETC, TO THE NORMAL POSITIONS BEFORE RETURNING THE ACFT TO FLT LINE STATUS IN AN EFFORT TO ENHANCE SAFETY AND SAFEGUARD AGAINST OVERLOOKING WHAT COULD BE THE OBVIOUS.

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.