Narrative:

The airplane had a write-up for a 'rudder limit on' in-flight. Apparently; maintenance was pressure testing the pitot system to find the problem with the rudder limiter sensor. They signed off the deferral and never removed the tape on the left side pitot tube. We were going from ZZZ1 to ZZZ2 with an aircraft swap. The aircraft that we were swapping to was undergoing a static pressure test. Our flight was not out for another hour. When I returned to the airplane; I preflted and found yellow electrical tape covering the left side pitot tube and static port along with the nose gear pin and 'C' clamp installed. I talked to the captain and asked if maintenance was still working on the plane. He said no. I told him what I found and we looked at the maintenance log only to find that everything was signed off. We called maintenance and had them remove the tape. They also rechked that all maintenance action was completed. The first sign that something was wrong was the nose pin and 'C' clamp still installed. These are not required in ZZZ1 for normal operations. I then noted the yellow tape on the pitot tube. Fortunately; it was bright yellow and easily seen. Following of SOP is an absolute must. It was 100 degrees and I do not know how long the maintenance workers were working in the heat. That could be a contributing factor.

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Original NASA ASRS Text

Title: A SAAB 340-B ACFT PREFLIGHT WALKAROUND FOUND ACFT WITH YELLOW ELECTRICAL TAPE COVERING THE LEFT SIDE PITOT TUBE AND STATIC PORT ALONG WITH THE NLG PIN AND 'C' CLAMP INSTALLED.

Narrative: THE AIRPLANE HAD A WRITE-UP FOR A 'RUDDER LIMIT ON' INFLT. APPARENTLY; MAINT WAS PRESSURE TESTING THE PITOT SYS TO FIND THE PROB WITH THE RUDDER LIMITER SENSOR. THEY SIGNED OFF THE DEFERRAL AND NEVER REMOVED THE TAPE ON THE L SIDE PITOT TUBE. WE WERE GOING FROM ZZZ1 TO ZZZ2 WITH AN ACFT SWAP. THE ACFT THAT WE WERE SWAPPING TO WAS UNDERGOING A STATIC PRESSURE TEST. OUR FLT WAS NOT OUT FOR ANOTHER HR. WHEN I RETURNED TO THE AIRPLANE; I PREFLTED AND FOUND YELLOW ELECTRICAL TAPE COVERING THE L SIDE PITOT TUBE AND STATIC PORT ALONG WITH THE NOSE GEAR PIN AND 'C' CLAMP INSTALLED. I TALKED TO THE CAPT AND ASKED IF MAINT WAS STILL WORKING ON THE PLANE. HE SAID NO. I TOLD HIM WHAT I FOUND AND WE LOOKED AT THE MAINT LOG ONLY TO FIND THAT EVERYTHING WAS SIGNED OFF. WE CALLED MAINT AND HAD THEM REMOVE THE TAPE. THEY ALSO RECHKED THAT ALL MAINT ACTION WAS COMPLETED. THE FIRST SIGN THAT SOMETHING WAS WRONG WAS THE NOSE PIN AND 'C' CLAMP STILL INSTALLED. THESE ARE NOT REQUIRED IN ZZZ1 FOR NORMAL OPS. I THEN NOTED THE YELLOW TAPE ON THE PITOT TUBE. FORTUNATELY; IT WAS BRIGHT YELLOW AND EASILY SEEN. FOLLOWING OF SOP IS AN ABSOLUTE MUST. IT WAS 100 DEGS AND I DO NOT KNOW HOW LONG THE MAINT WORKERS WERE WORKING IN THE HEAT. THAT COULD BE A CONTRIBUTING FACTOR.

Data retrieved from NASA's ASRS site as of January 2009 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.