Narrative:

Our aircraft is equipped with a multi-function display ('mfd') which provides a geo-synchronized position of the aircraft on commercial airport diagrams; as well as approach charts. The commercial databases for the aircraft were all current; and there was no position error indicated by the FMS. In fact; the aircraft's position was accurately depicting our position at the general aviation ramp after engine start. We also had available a paper copy of the airport diagram; as well as a garmin 696 which displays a similar 'safe taxi' chart which depicts the location of the aircraft on the airport. Both the mfd and the garmin 696 'safe taxi' displays concurred with the position of our aircraft before we began any movement. These systems have proven to be very accurate for past 3-4 years that they have been installed in this aircraft. We then contacted ground control and we were instructed to taxi our aircraft out of the general aviation ramp to taxiway 'M' and hold short of 'M6'. We taxied north on taxiway 'M'; and continually monitored our position on taxiway 'M' utilizing the multi-function display which was set to a range of 0.25 NM and displaying the 'own ship' symbol for our aircraft accurately on the commercial airport chart as we progressed north. Ground control contacted us and stated that we had passed 'M6' and were approaching 'M7'; however; both the mfd and the 'safe taxi' display of the garmin 696 indicated that we were still approaching 'M6'. For informational purposes; 'M6' is a high-speed exit for runway 35L - as such; it is not perpendicular to taxiway 'M'; but rather slanted at a 45 degree angle to the southeast - or 'behind' and to the right of taxiway 'M' if you are taxing northbound. We did not see our aircraft passing any taxiway marking for 'M6'; nor did the mfd or safe-taxi displays indicate that we had gone beyond 'M6' on taxiway M. In addition; we did not see any 'hold' lines on taxiway 'M' at the intersection 'M6'. We immediately stopped the aircraft. The ground controller then stated that he was intending to allow another aircraft which was landing on runway 35L to exit at 'M6' and proceed in front of us. At no time did we see the other aircraft to which the ground controller was referring. At this point; the ground controller then instructed us to proceed north on 'M' and then taxi westbound on 'aa' and to contract ramp control when we reached concourse 'a'; which we did. At this point; and to avoid any further issues while taxiing; we requested 'progressive' taxi instructions to runway 34L; located on the west side of den. By way of background; we have operated out of den on multiple occasions in the past; and in fact; this had been our 4th operation in or out of den within the past 48 hours. Nonetheless; den is 'challenging' - and even with the technology we maintain giving us situational awareness; we have always found some of the markings at den to be difficult to see. What is most disturbing is that the 'safe taxi' feature; and the mfd charts; have always accurately depicted our position on the airport; and we are at a loss to understand this discrepancy. Adding to all of this; the general aviation ramp is located on the east side of the airport - and each time we are given taxi instructions to runways on the west side of the airport; many (not all) of the ground controllers/ramp controllers issue 'rapid fire'; multiple taxi route instructions - interjecting ramp control frequencies - all without pausing or 'taking a breath'. While long taxiing is understood when operating out of high-traffic airports such as den; the oblique intersection of 'M' and 'M6' contributed; and the taxi markings for aa are very difficult to see.

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Original NASA ASRS Text

Title: CE525 Captain is instructed to taxi north on Taxiway M and hold short of Taxiway M6 at DEN. The aircraft is equipped with an MFD displaying the airport diagram as a moving map a Garmin 696 with safe taxi chart and a paper airport diagram. The reporter is advised by Ground Control that he has passed M6 and to continue with a left on AA and contact Ramp.

Narrative: Our aircraft is equipped with a Multi-Function Display ('MFD') which provides a geo-synchronized position of the aircraft on Commercial Airport Diagrams; as well as Approach Charts. The Commercial databases for the aircraft were all current; and there was no position error indicated by the FMS. In fact; the aircraft's position was accurately depicting our position at the General Aviation ramp after engine start. We also had available a paper copy of the Airport Diagram; as well as a Garmin 696 which displays a similar 'Safe Taxi' chart which depicts the location of the aircraft on the airport. Both the MFD and the Garmin 696 'Safe Taxi' displays concurred with the position of our aircraft before we began any movement. These systems have proven to be very accurate for past 3-4 years that they have been installed in this aircraft. We then contacted Ground Control and we were instructed to taxi our aircraft out of the General Aviation Ramp to Taxiway 'M' and hold short of 'M6'. We taxied north on Taxiway 'M'; and continually monitored our position on taxiway 'M' utilizing the Multi-Function Display which was set to a range of 0.25 NM and displaying the 'Own Ship' symbol for our aircraft accurately on the Commercial Airport Chart as we progressed north. Ground Control contacted us and stated that we had passed 'M6' and were approaching 'M7'; however; both the MFD and the 'Safe Taxi' display of the Garmin 696 indicated that we were still approaching 'M6'. For informational purposes; 'M6' is a high-speed exit for Runway 35L - as such; it is not perpendicular to Taxiway 'M'; but rather slanted at a 45 degree angle to the southeast - or 'behind' and to the right of Taxiway 'M' if you are taxing northbound. We did not see our aircraft passing any taxiway marking for 'M6'; nor did the MFD or Safe-Taxi displays indicate that we had gone beyond 'M6' on Taxiway M. In addition; we did not see any 'Hold' lines on Taxiway 'M' at the intersection 'M6'. We immediately stopped the aircraft. The Ground Controller then stated that he was intending to allow another aircraft which was landing on Runway 35L to exit at 'M6' and proceed in front of us. At no time did we see the other aircraft to which the Ground Controller was referring. At this point; the Ground Controller then instructed us to proceed north on 'M' and then taxi westbound on 'AA' and to contract Ramp Control when we reached Concourse 'A'; which we did. At this point; and to avoid any further issues while taxiing; we requested 'progressive' taxi instructions to Runway 34L; located on the west side of DEN. By way of background; we have operated out of DEN on multiple occasions in the past; and in fact; this had been our 4th operation in or out of DEN within the past 48 hours. Nonetheless; DEN is 'challenging' - and even with the technology we maintain giving us situational awareness; we have always found some of the markings at DEN to be difficult to see. What is most disturbing is that the 'Safe Taxi' feature; and the MFD charts; have always accurately depicted our position on the airport; and we are at a loss to understand this discrepancy. Adding to all of this; the General Aviation Ramp is located on the east side of the airport - and each time we are given taxi instructions to runways on the west side of the airport; many (not all) of the Ground Controllers/Ramp Controllers issue 'rapid fire'; multiple taxi route instructions - interjecting Ramp Control frequencies - all without pausing or 'taking a breath'. While long taxiing is understood when operating out of high-traffic airports such as DEN; the oblique intersection of 'M' and 'M6' contributed; and the taxi markings for AA are very difficult to see.

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.