Narrative:

We were cleared to taxi to runway 28 via east; cross 35/17. We had moving map of taxiway on the mfd and as we approached E1 the map showed a bend to right. We followed the map more than paying attention to signs and turned onto taxiway E1. The tower stopped us; then cleared us to taxi on runway 4/22 to runway 28. We should not have concentrated on the mfd map as closely as we did. We should only have used it as confirmation of taxi signs. Note: earlier runway 4/22 was closed. I don't know if it was still closed when we entered taxiway E1; if we went onto runway 4/22 or if tower stopped us prior to doing so. The surface markings were faded and we could not tell if we were on runway 35; runway 4 or just E1.

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Original NASA ASRS Text

Title: Cleared to cross Runway 17/35 and taxi to Runway 28 via Echo at WAL; the flight crew of a Super King Air inadvertently entered E1 enroute and may have incurred on Runway 4/22. Ground Control alerted them and provided an alternative clearance to Runway 28. Over-reliance on a moving map airport MFD display likely contributed to their error.

Narrative: We were cleared to taxi to Runway 28 via E; cross 35/17. We had moving map of taxiway on the MFD and as we approached E1 the map showed a bend to right. We followed the map more than paying attention to signs and turned onto Taxiway E1. The Tower stopped us; then cleared us to taxi on Runway 4/22 to Runway 28. We should not have concentrated on the MFD map as closely as we did. We should only have used it as confirmation of taxi signs. Note: Earlier Runway 4/22 was closed. I don't know if it was still closed when we entered taxiway E1; if we went onto Runway 4/22 or if Tower stopped us prior to doing so. The surface markings were faded and we could not tell if we were on Runway 35; Runway 4 or just E1.

Data retrieved from NASA's ASRS site as of July 2013 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.