Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP)
Confusion
Deviation / Discrepancy - Procedural Clearance; Ground Incursion Taxiway
Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Returned To Clearance
Airport; Human Factors; Aircraft
When we made our initial call to Grnd Cntl for taxi clearance; we were given 'Taxi to 1R via Charlie; Charlie 2; Bravo; Delta; Cross 25R'. The First Officer and I briefly reviewed the instructions and began to taxi. Exiting the ramp I was initially watching the wing walkers for [another departure] as they were waiting for us to pass so they could push back. Continuing to taxi; I noticed many construction barricades ahead of us as well as to our left and the area was very dark which was complicated by our runway turn off light being inop. I made the right turn onto the taxiway which we thought was Charlie but was told by ATC that the taxiway we were on was Quebec. I then made the left turn on C1 to join taxiway C. At no time was there any traffic conflict. The rest of the taxi to runway 1R was uneventful. The lighting and signage is very poor in this area and all of the barricades just added to the confusion. Our right runway turnoff light being inop just added to the poor lighting since we were turning right out of the ramp area.
I became distracted and failed to backup the Capt during taxi in poor taxi conditions bad signage; poorly lit. Resulting in a wrong turn down a non cleared taxiway.
When departing the cargo ramp at LAS an air carrier jet turned right on Taxiway Q vice C as cleared. Poor signage and ramp lighting plus a deferred inoperative runway turnoff taxi light were cited as contributing factors.