|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||navaid : act.vortac|
|Altitude||msl single value : 22000|
|Controlling Facilities||artcc : zfw.artcc|
|Make Model Name||Small Transport|
2 Turbojet Eng
|Navigation In Use||Other|
|Flight Phase||cruise : level|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : atp|
|Experience||flight time last 90 days : 100|
flight time total : 15000
flight time type : 100
|Affiliation||government : faa|
|Function||controller : radar|
|Anomaly||aircraft equipment problem : critical|
|Independent Detector||other flight crewa|
|Resolutory Action||controller : provided flight assist|
flight crew : landed as precaution
A specific combination of 'programming inputs' caused the navigation system to malfunction and shortly after that the primary flight displays started into a cycle of 'automatic-reversion' that was never completed. The displays had information building/disappearing at a rate of once per second. Primary flight information was never lost but was difficult to interpret due to all the peripheral display activity. Xchks with the standby flight instruments provided confidence in aircraft control. The communications frequency 'automatic-switched' to 121.5 MHZ; contact was established with a TRACON facility in the vicinity and coordination was completed to allow descent to an uneventful landing. The malfunction has been duplicated by the manufacturer and work is in progress to isolate and correct the problem. A phone call was made to TRACON after landing and the situation explained -- no further contact has transpired with the ARTCC but contact information was given if ATC needed more information.
Original NASA ASRS Text
Title: LIGHT JET PILOT EXPERIENCES NAVIGATION SYSTEM MALFUNCTION AND REQUIRES ASSISTANCE FROM ATC TO LAND SAFELY.
Narrative: A SPECIFIC COMBINATION OF 'PROGRAMMING INPUTS' CAUSED THE NAV SYS TO MALFUNCTION AND SHORTLY AFTER THAT THE PRIMARY FLT DISPLAYS STARTED INTO A CYCLE OF 'AUTO-REVERSION' THAT WAS NEVER COMPLETED. THE DISPLAYS HAD INFO BUILDING/DISAPPEARING AT A RATE OF ONCE PER SECOND. PRIMARY FLT INFO WAS NEVER LOST BUT WAS DIFFICULT TO INTERPRET DUE TO ALL THE PERIPHERAL DISPLAY ACTIVITY. XCHKS WITH THE STANDBY FLT INSTS PROVIDED CONFIDENCE IN ACFT CTL. THE COMS FREQ 'AUTO-SWITCHED' TO 121.5 MHZ; CONTACT WAS ESTABLISHED WITH A TRACON FACILITY IN THE VICINITY AND COORD WAS COMPLETED TO ALLOW DSCNT TO AN UNEVENTFUL LNDG. THE MALFUNCTION HAS BEEN DUPLICATED BY THE MANUFACTURER AND WORK IS IN PROGRESS TO ISOLATE AND CORRECT THE PROB. A PHONE CALL WAS MADE TO TRACON AFTER LNDG AND THE SITUATION EXPLAINED -- NO FURTHER CONTACT HAS TRANSPIRED WITH THE ARTCC BUT CONTACT INFO WAS GIVEN IF ATC NEEDED MORE INFO.
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.