Narrative:

We had an XA30 show time in esc for a flight to pln, and then to dtw. It was dark so my first officer grabbed a flashlight and headed out to do the preflight. He came back and said everything looked fine. I'm a high minimums captain so the leg was mine to fly. On takeoff, all indications were normal. I was looking down the runway, glanced at the power instruments quickly to confirm proper setting, then back outside down the runway. The first officer called V1, then vr. I started pulling back on the yoke to set 10 degrees pitch in. I came inside and confirmed pitch. I then noticed the vvi jiggle. Then I noticed the airspeed was at around 60 KTS. I knew this was incorrect so I went to the standby indicator. This looked to be operating normally indicating about 150 KTS. I decided to fly straight ahead and clean things up with the completion of the after takeoff checklist. It was VFR so I continued straight ahead on course and gaining altitude. I then asked my first officer if he checked the pitots. He said he had. I then got on the radio to esc station and asked her if there was any chance a pitot cover could have been left on the aircraft and if she had 3 in possession. She said there was only 1, and that she had removed it. Now I was thinking we had some other problem, such as an air data computer failure. I decided to continue towards pln and land into the wind rather than go back to esc and land in the dark with a 90 degree crosswind. Pln was clear and good VFR. Maintenance then asked if I would overfly pln on to dtw. I told them I would need good VFR WX and approval from the flight department. They gave us to dispatch who gave us the WX, which was good VFR, and that dispatch had approved for us to go on to dtw. I also figured there is better crash fire rescue equipment in dtw. We made all the appropriate changes to our release and continued VFR to dtw. We were assigned 11000 ft. I then asked ATC what altitude they were showing us at. They said 10700 ft. I then decided to declare an emergency because we didn't really know what the problem was and to help explain our altdevs. We were also keeping our airspeed around 150 KTS because the rudder limiter light also came on with no input to the air data computer. I did not want ATC to expect a higher airspeed out of us either. We came into dtw and landed without incident. As soon as we opened the door, I looked to see a black rubber tube on the left lower pitot tube. A mechanic came and removed it. They pressure tested the system and no damage was done. The agent in esc had in fact removed 1 pitot cover. The evening agent had put 2 covers on the aircraft the night before (1 with a flag attached, the other with no flag). There was 1 on each side of the aircraft. The one with the flag was removed by the agent. The one without the flag was missed by all involved.

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Original NASA ASRS Text

Title: AN ACR SF340B FLC DEPARTS WITH 1 PITOT COVER STILL INSTALLED AND CONTINUES THE FLT SUCCESSFULLY TO AN ALTERNATE ARPT BY XCHKING BTWN THE STANDBY INSTS AND THE CORRECTLY OPERATING SET.

Narrative: WE HAD AN XA30 SHOW TIME IN ESC FOR A FLT TO PLN, AND THEN TO DTW. IT WAS DARK SO MY FO GRABBED A FLASHLIGHT AND HEADED OUT TO DO THE PREFLT. HE CAME BACK AND SAID EVERYTHING LOOKED FINE. I'M A HIGH MINIMUMS CAPT SO THE LEG WAS MINE TO FLY. ON TKOF, ALL INDICATIONS WERE NORMAL. I WAS LOOKING DOWN THE RWY, GLANCED AT THE PWR INSTS QUICKLY TO CONFIRM PROPER SETTING, THEN BACK OUTSIDE DOWN THE RWY. THE FO CALLED V1, THEN VR. I STARTED PULLING BACK ON THE YOKE TO SET 10 DEGS PITCH IN. I CAME INSIDE AND CONFIRMED PITCH. I THEN NOTICED THE VVI JIGGLE. THEN I NOTICED THE AIRSPD WAS AT AROUND 60 KTS. I KNEW THIS WAS INCORRECT SO I WENT TO THE STANDBY INDICATOR. THIS LOOKED TO BE OPERATING NORMALLY INDICATING ABOUT 150 KTS. I DECIDED TO FLY STRAIGHT AHEAD AND CLEAN THINGS UP WITH THE COMPLETION OF THE AFTER TKOF CHKLIST. IT WAS VFR SO I CONTINUED STRAIGHT AHEAD ON COURSE AND GAINING ALT. I THEN ASKED MY FO IF HE CHKED THE PITOTS. HE SAID HE HAD. I THEN GOT ON THE RADIO TO ESC STATION AND ASKED HER IF THERE WAS ANY CHANCE A PITOT COVER COULD HAVE BEEN LEFT ON THE ACFT AND IF SHE HAD 3 IN POSSESSION. SHE SAID THERE WAS ONLY 1, AND THAT SHE HAD REMOVED IT. NOW I WAS THINKING WE HAD SOME OTHER PROB, SUCH AS AN AIR DATA COMPUTER FAILURE. I DECIDED TO CONTINUE TOWARDS PLN AND LAND INTO THE WIND RATHER THAN GO BACK TO ESC AND LAND IN THE DARK WITH A 90 DEG XWIND. PLN WAS CLR AND GOOD VFR. MAINT THEN ASKED IF I WOULD OVERFLY PLN ON TO DTW. I TOLD THEM I WOULD NEED GOOD VFR WX AND APPROVAL FROM THE FLT DEPT. THEY GAVE US TO DISPATCH WHO GAVE US THE WX, WHICH WAS GOOD VFR, AND THAT DISPATCH HAD APPROVED FOR US TO GO ON TO DTW. I ALSO FIGURED THERE IS BETTER CFR IN DTW. WE MADE ALL THE APPROPRIATE CHANGES TO OUR RELEASE AND CONTINUED VFR TO DTW. WE WERE ASSIGNED 11000 FT. I THEN ASKED ATC WHAT ALT THEY WERE SHOWING US AT. THEY SAID 10700 FT. I THEN DECIDED TO DECLARE AN EMER BECAUSE WE DIDN'T REALLY KNOW WHAT THE PROB WAS AND TO HELP EXPLAIN OUR ALTDEVS. WE WERE ALSO KEEPING OUR AIRSPD AROUND 150 KTS BECAUSE THE RUDDER LIMITER LIGHT ALSO CAME ON WITH NO INPUT TO THE AIR DATA COMPUTER. I DID NOT WANT ATC TO EXPECT A HIGHER AIRSPD OUT OF US EITHER. WE CAME INTO DTW AND LANDED WITHOUT INCIDENT. AS SOON AS WE OPENED THE DOOR, I LOOKED TO SEE A BLACK RUBBER TUBE ON THE L LOWER PITOT TUBE. A MECH CAME AND REMOVED IT. THEY PRESSURE TESTED THE SYS AND NO DAMAGE WAS DONE. THE AGENT IN ESC HAD IN FACT REMOVED 1 PITOT COVER. THE EVENING AGENT HAD PUT 2 COVERS ON THE ACFT THE NIGHT BEFORE (1 WITH A FLAG ATTACHED, THE OTHER WITH NO FLAG). THERE WAS 1 ON EACH SIDE OF THE ACFT. THE ONE WITH THE FLAG WAS REMOVED BY THE AGENT. THE ONE WITHOUT THE FLAG WAS MISSED BY ALL INVOLVED.

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.