Narrative:

We showed at xa:00 local; I did a preflight; which included removing all pins and pitot covers. We fueled; and I did another walk around; looking for anything abnormal; such as flags; unlocked panels or bent metal. When the passengers arrived I did another final walk around before takeoff. I was the flying pilot in the left seat; and after the normal takeoff I was told of an airspeed anomaly on the copilot's side. I continued to fly to a safe altitude; whence the first officer went through the checklist for his airspeed malfunction. We complied with the checklist; and were aware of any system degradation. As we reached a higher altitude; we called the company and informed the assistant chief pilot of the situation. He agreed that the weather was clear the entire route; our fuel was sufficient; and we could proceed to our destination safely if we were comfortable. We continued and checked our fom to make sure we were complying with all limitations. The trip was uneventful; and we landed safely with no further note. During postflight it was found that when I pulled the pitot cover off from the copilot's side; the string attaching the flag to the rubber cover broke; so that in my hand was only the flag and not the pitot cover. When I stowed the flag along with the rest of the covers; I missed that the pitot cover had broken and was still on the pitot tube. On my subsequent walk arounds I missed this broken cover; because it was still dark; the cover is small and black; and I was looking for flags and other obvious missed items. Removing the pitot cover by the grabbing the rubber part would ensure proper removal; along with touching each pitot to verify that it is indeed clear. A stronger attachment between the flag and the pitot would also be good; to ensure it does not break so easily. Also; during a night pre-flight; extra care must be taken to ensure everything is as should be.

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Original NASA ASRS Text

Title: An HS-125-800XPC crew reported that during the early morning preflight the Captain tried to pull the right pitot tube cover off but only the cover's flag was removed. In flight an airspeed discrepancy was noted but the pitot cover was not discovered until they reached their destination.

Narrative: We showed at XA:00 local; I did a preflight; which included removing all pins and pitot covers. We fueled; and I did another walk around; looking for anything abnormal; such as flags; unlocked panels or bent metal. When the passengers arrived I did another final walk around before takeoff. I was the flying pilot in the left seat; and after the normal takeoff I was told of an airspeed anomaly on the copilot's side. I continued to fly to a safe altitude; whence the First Officer went through the checklist for his airspeed malfunction. We complied with the checklist; and were aware of any system degradation. As we reached a higher altitude; we called the Company and informed the Assistant Chief Pilot of the situation. He agreed that the weather was clear the entire route; our fuel was sufficient; and we could proceed to our destination safely if we were comfortable. We continued and checked our FOM to make sure we were complying with all limitations. The trip was uneventful; and we landed safely with no further note. During postflight it was found that when I pulled the pitot cover off from the copilot's side; the string attaching the flag to the rubber cover broke; so that in my hand was only the flag and not the pitot cover. When I stowed the flag along with the rest of the covers; I missed that the pitot cover had broken and was still on the pitot tube. On my subsequent walk arounds I missed this broken cover; because it was still dark; the cover is small and black; and I was looking for flags and other obvious missed items. Removing the pitot cover by the grabbing the rubber part would ensure proper removal; along with touching each pitot to verify that it is indeed clear. A stronger attachment between the flag and the pitot would also be good; to ensure it does not break so easily. Also; during a night pre-flight; extra care must be taken to ensure everything is as should be.

Data retrieved from NASA's ASRS site as of April 2012 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.