Narrative:

While getting vectored into bur; both my first officer and I believe we were given the instructions to steer to a 160 degree heading and descend to maintain 4;000 ft and also to report both the vny and bur airports in sight. It was a clear night and the northern peaks of the valley were visible against the lights of the city. Having done extensive flying in this area in my career and knowing the terrain around there; I had a strange feeling as we descended through 5;000 MSL; but remember looking up at the altitude selector and seeing 4;000 set; which was verified and pointed at by both crew members when we received the instructions; per SOP. At that point; I remember decreasing my descent rate from about 1;200 FPM to around 600 FPM and I also began my speed reduction. Almost simultaneously at approximately 4;500 ft MSL; we received a single 'terrain; terrain; pull up' warning from GPWS; and a call from the socal TRACON station; 'friendly conversation here about your altitude; verify you have van nuys and burbank in sight' as if to imply we had descended below an altitude he gave us. We informed him that at that point; we did; in fact; have both airports in sight and also included that we were at 4;400 descending to 4;000. At that point; he cleared us for the visual approach to bur and later handed us off to the tower not long after that without saying anything else about our altitude.when we received the GPWS aural warning; the first officer had the terrain feature displayed on his mfd. I did not. Upon getting the warning; terrain features should have automatically appeared on the pilot's side mfd; but never did. This led me to believe this was a spurious and incorrect indication; although I shallowed my descent rate further nonetheless. The aircraft we were flying was having some minor electrical issues on that flight since shortly after takeoff. We received two annunciator lights (fuel lo lvl) which were incorrect as we had just topped off the airplane for our trans-continental trip and furthermore; we didn't get a 'level' light associated with that in our overhead panel. Also; our landing lights were working on departure; but they were both inoperative on the descent into bur. These were factors that were thought about rather quickly when the situation unfolded. Note: distance and radial given above are estimates. Furthermore; for clarification; I did not consider slowing my descent rate to be taking 'evasive action'. At this very minute; I do not know if we actually did have an altitude deviation! The controller was vague in his verbiage; but I find it more than coincidental that his transmission came at the same time as the GPWS warning.

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Original NASA ASRS Text

Title: DA2000 Captain experiences a terrain warning descending to 4;000 in VMC during arrival to BUR from the north. ATC questioned the reporter's altitude moments later and asked him to verify his visual status.

Narrative: While getting vectored into BUR; both my First Officer and I believe we were given the instructions to steer to a 160 degree heading and descend to maintain 4;000 FT and also to report both the VNY and BUR airports in sight. It was a clear night and the northern peaks of the valley were visible against the lights of the city. Having done extensive flying in this area in my career and knowing the terrain around there; I had a strange feeling as we descended through 5;000 MSL; but remember looking up at the altitude selector and seeing 4;000 set; which was verified and pointed at by both crew members when we received the instructions; per SOP. At that point; I remember decreasing my descent rate from about 1;200 FPM to around 600 FPM and I also began my speed reduction. Almost simultaneously at approximately 4;500 FT MSL; we received a single 'TERRAIN; TERRAIN; PULL UP' warning from GPWS; and a call from the SoCal TRACON station; 'friendly conversation here about your altitude; verify you have Van Nuys and Burbank in sight' as if to imply we had descended below an altitude he gave us. We informed him that at that point; we did; in fact; have both airports in sight and also included that we were at 4;400 descending to 4;000. At that point; he cleared us for the visual approach to BUR and later handed us off to the Tower not long after that without saying anything else about our altitude.When we received the GPWS aural warning; the First Officer had the terrain feature displayed on his MFD. I did not. Upon getting the warning; terrain features SHOULD have automatically appeared on the pilot's side MFD; but never did. This led me to believe this was a spurious and incorrect indication; although I shallowed my descent rate further nonetheless. The aircraft we were flying was having some minor electrical issues on that flight since shortly after takeoff. We received two annunciator lights (Fuel Lo LVL) which were incorrect as we had just topped off the airplane for our trans-continental trip and furthermore; we didn't get a 'level' light associated with that in our overhead panel. Also; our landing lights were working on departure; but they were BOTH inoperative on the descent into BUR. These were factors that were thought about rather quickly when the situation unfolded. NOTE: Distance and radial given above are estimates. Furthermore; for clarification; I did not consider slowing my descent rate to be taking 'evasive action'. At this very minute; I do not know if we actually did have an altitude deviation! The Controller was vague in his verbiage; but I find it more than coincidental that his transmission came at the same time as the GPWS warning.

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.