Narrative:

The crew reported for duty for a part 91 flight to pick up the airplane owner. Prior to departure the crew conducted a full preflight. No anomalies; malfunctions or defects were noted. As a result of the preflight inspection the crew determined the airplane was in airworthy condition and departed to pick up the owner and return to home base. No defects were noted upon return. The day before the crew had experienced a partial malfunction of the pilot and co-pilot pfd displays that was temporary in nature. During initial climb on the last leg of the day the flight director failed; the altitude preselect stopped displaying an altitude and the background momentarily went white. Almost immediately the system reset itself and the background returned to normal. Initially the flight director did not reappear in spite of attempts by the co-pilot (pilot monitoring) to reset it. The altitude preselect showed an altitude as soon as the altitude knob was twisted clockwise and was reset to the original assigned altitude. The second attempt from the pilot monitoring to bring the flight director back into view was successful. Once everything returned all systems and displays continued working normally for the remainder of the flight. All displays and modes were crosschecked against standby instruments and navigation receivers. No anomalies were noted. As a result of the display malfunction the crew had missed an altitude assignment that subsequently became a matter of great concern to the crew. The crew discussed what could have caused the partial and temporary display malfunction and determined the likely cause to be a jolt that we felt through the nose wheel as the airplane accelerated at V1. The nose wheel hit some kind of bump on the runway and this was felt through the airframe. In other words; we determined that the likely cause was an event external to the airplane; not a fault of the electronics themselves. Upon arrival the captain contacted the chief pilot. The incident was reported and discussed. The chief pilot requested a report in writing from each pilot. Post flight checks by the crew revealed no anomalies/malfunctions or defects. The next day; upon return the crew discussed the previous day's display anomalies with one of the maintenance technicians. Maintenance expressed no particular concern during the conversation and remarked that they had received similar observations of soft failures that reset in flight and that upon inspection could not be replicated. The crew stopped by the chief pilot's office and discussed the reports to be filed. They were filed later that evening. The crew received no response about these reports until three days later. The airplane was released by the company for an international trip; part 91; for the airplane owner to be started in two days. The crew reported for duty; and conducted a full preflight. No defects were noted and the crew with the owner departed. A total of 4 legs were flown that day; during two of which the crew encountered IFR conditions with moderate rain and turbulence. An instrument approach had to be flown into tucson; az for a fuel stop; followed by an instrument departure in rain and turbulence. Throughout all 4 legs that day there were no malfunctions experienced. The trip ended without incident. The crew was contacted by the company a day later about the lack of a discrepancy write-up concerning the partial and temporary display failure. The crew had not filed a discrepancy report because there were no hard failures of any of the displays or avionics; the temporary display interruption was thought to have been caused by a temporary external event; and because the crew was preoccupied with the altitude deviation. As pilots we have no training in aircraft systems matching the level of a&P; yet we are expected to be able make a determination as to the airworthiness of the airplane before every flight. We are considered to be competent to do sofrom a private pilot on up. However; our decision making is now being questioned; even after a FAA licensed a&P inspected the equipment; could not duplicate the faults on the ground; and returned the airplane to service. The lessons learned are to: 1. Not take anything for granted. 2. Not to get distracted from the cause (why did the malfunction happen) by the effect (missing the altitude assignment).3. Back up your thinking with the expertise of other professionals.

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Original NASA ASRS Text

Title: CE525 First Officer experienced momentary PFD failure during takeoff which is quickly corrected; but not before an altitude deviations occured. The crew is chided by the company for not entering a maintenance discrepancy in the logbook.

Narrative: The crew reported for duty for a Part 91 flight to pick up the airplane owner. Prior to departure the crew conducted a full preflight. No anomalies; malfunctions or defects were noted. As a result of the preflight inspection the crew determined the airplane was in airworthy condition and departed to pick up the owner and return to home base. No defects were noted upon return. The day before the crew had experienced a partial malfunction of the pilot and co-pilot PFD displays that was temporary in nature. During initial climb on the last leg of the day the flight director failed; the altitude preselect stopped displaying an altitude and the background momentarily went white. Almost immediately the system reset itself and the background returned to normal. Initially the flight director did not reappear in spite of attempts by the co-pilot (pilot monitoring) to reset it. The altitude preselect showed an altitude as soon as the ALT knob was twisted clockwise and was reset to the original assigned altitude. The second attempt from the pilot monitoring to bring the flight director back into view was successful. Once everything returned all systems and displays continued working normally for the remainder of the flight. All displays and modes were crosschecked against standby instruments and navigation receivers. No anomalies were noted. As a result of the display malfunction the crew had missed an altitude assignment that subsequently became a matter of great concern to the crew. The crew discussed what could have caused the partial and temporary display malfunction and determined the likely cause to be a jolt that we felt through the nose wheel as the airplane accelerated at V1. The nose wheel hit some kind of bump on the runway and this was felt through the airframe. In other words; we determined that the likely cause was an event external to the airplane; not a fault of the electronics themselves. Upon arrival the Captain contacted the Chief Pilot. The incident was reported and discussed. The Chief Pilot requested a report in writing from each pilot. Post flight checks by the crew revealed no anomalies/malfunctions or defects. The next day; upon return the crew discussed the previous day's display anomalies with one of the Maintenance Technicians. Maintenance expressed no particular concern during the conversation and remarked that they had received similar observations of soft failures that reset in flight and that upon inspection could not be replicated. The crew stopped by the Chief Pilot's office and discussed the reports to be filed. They were filed later that evening. The crew received no response about these reports until three days later. The airplane was released by the company for an international trip; Part 91; for the airplane owner to be started in two days. The crew reported for duty; and conducted a full preflight. No defects were noted and the crew with the owner departed. A total of 4 legs were flown that day; during two of which the crew encountered IFR conditions with moderate rain and turbulence. An instrument approach had to be flown into Tucson; AZ for a fuel stop; followed by an instrument departure in rain and turbulence. Throughout all 4 legs that day there were no malfunctions experienced. The trip ended without incident. The crew was contacted by the company a day later about the lack of a discrepancy write-up concerning the partial and temporary display failure. The crew had not filed a discrepancy report because there were no hard failures of any of the displays or avionics; the temporary display interruption was thought to have been caused by a temporary external event; and because the crew was preoccupied with the altitude deviation. As pilots we have no training in aircraft systems matching the level of A&P; yet we are expected to be able make a determination as to the airworthiness of the airplane before every flight. We are considered to be competent to do sofrom a private pilot on up. However; our decision making is now being questioned; even after a FAA licensed A&P inspected the equipment; could not duplicate the faults on the ground; and returned the airplane to service. The lessons learned are to: 1. Not take anything for granted. 2. Not to get distracted from the cause (why did the malfunction happen) by the effect (missing the altitude assignment).3. Back up your thinking with the expertise of other professionals.

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.