MD80 flight crew has ramp excursion when taxiing to gate.

Attributes
ACN	325544
Time
Date	199512
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : iah
State Reference	TX
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	MD-80 Series (DC-9-80) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	ground : parked ground : holding ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : instrument pilot : commercial
Experience	flight time last 90 days : 60 flight time total : 9000 flight time type : 250
ASRS Report	325544
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	other anomaly other other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

We were taxiing onto our ramp at night, and there was some confusion about whether our gate was occupied. We taxied over to the edge of the ramp to stay out of the way of other aircraft leaving the ramp, while we worked on the problem of the gate. The problem with the gate was that the gates had been renumbered and this is a new gate. One airport chart does not show this gate and has the old gate numbers. The other shows this gate with the new numbers. We accidently were at first using the old chart, when we came to the ramp. Once on the ramp we realized the mistake and taxied over to the side to clear the ramp and consult the other chart. In the process of doing this the right gear went off the ramp and sank in the mud. The passenger and baggage were off loaded there and maintenance personnel dug out the right gear and pushed the aircraft back on the ramp. No one was hurt, and as far as I know, no damage was done to the aircraft. Contributing factors: the ramp edge is not lit and on a dark night this might help to align yourself when taxiing on the ramp.

Original NASA ASRS Text

Title: MD80 FLC HAS RAMP EXCURSION WHEN TAXIING TO GATE.

Narrative: WE WERE TAXIING ONTO OUR RAMP AT NIGHT, AND THERE WAS SOME CONFUSION ABOUT WHETHER OUR GATE WAS OCCUPIED. WE TAXIED OVER TO THE EDGE OF THE RAMP TO STAY OUT OF THE WAY OF OTHER ACFT LEAVING THE RAMP, WHILE WE WORKED ON THE PROB OF THE GATE. THE PROB WITH THE GATE WAS THAT THE GATES HAD BEEN RENUMBERED AND THIS IS A NEW GATE. ONE ARPT CHART DOES NOT SHOW THIS GATE AND HAS THE OLD GATE NUMBERS. THE OTHER SHOWS THIS GATE WITH THE NEW NUMBERS. WE ACCIDENTLY WERE AT FIRST USING THE OLD CHART, WHEN WE CAME TO THE RAMP. ONCE ON THE RAMP WE REALIZED THE MISTAKE AND TAXIED OVER TO THE SIDE TO CLR THE RAMP AND CONSULT THE OTHER CHART. IN THE PROCESS OF DOING THIS THE R GEAR WENT OFF THE RAMP AND SANK IN THE MUD. THE PAX AND BAGGAGE WERE OFF LOADED THERE AND MAINT PERSONNEL DUG OUT THE R GEAR AND PUSHED THE ACFT BACK ON THE RAMP. NO ONE WAS HURT, AND AS FAR AS I KNOW, NO DAMAGE WAS DONE TO THE ACFT. CONTRIBUTING FACTORS: THE RAMP EDGE IS NOT LIT AND ON A DARK NIGHT THIS MIGHT HELP TO ALIGN YOURSELF WHEN TAXIING ON THE RAMP.

Data retrieved from NASA's ASRS site as of July 2007 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.