Narrative:

I was advised of a runway incursion by controllers and management at the facility. I was not working during the time of the occurrence. However; I had the opportunity to listen to the voice recordings and asde video playback of the event. It is my belief that having the 2 local control position combined (local control 2 and local control 3) was a contributing factor for this runway incursion. The voice tape demonstrates the frequency congestion and distrs that the controller had to deal with during the time of the error. Las vegas is unique in the large volume of helicopters that operate within the class B airspace. At the las vegas control tower the local control 2 position is the position that controls the traffic on the north/south parallel runway 19L/right. Local control 2 issues takeoff and landing clrncs to the north/south runways in addition to receiving coords for crossing traffic from ground control; etc. At the time of the incident; local control 2 was combined with local control 3. Local control 3 has the 'footprint' of the class B airspace for las tower. Local control 3 works all of the helicopters within the las tower airspace below 3000 ft. This includes pre-assigned rtes; overflts; photo missions; police and life-flight helicopters; etc. When working local control 3 you are required to radar identify traffic and monitor transitions into; out of; and through the las vegas class B airspace. For this reason I see local control 3 as a radar position. During the time of the incident local control 2 and local control 3 were combined. Air carrier X B737 departed runway 19L while aircraft Y was crossing the runway. All necessary coordination for the crossing was done on a recorded line with the ground controller as prescribed by the 7110.65. The controller's memory joggers were placed on the counter top in accordance with the facility SOP. With both of these safety nets in place; the system still failed. The controller's attention was split between the radar scope and the runways; because he was working '2 different' position. The above should illustrate the conflict with the 2 position. The local control 2's primary responsibility is the runway and scanning out the tower windows. While local control 3's primary responsibility is the radar scope and scanning the airspace. These 2 inherently different position should only be combined when traffic volume is at a minimum. The combining of these 2 position has become more common with the decrease in staffing levels at las vegas tower. Keeping these 2 position separate is a vital part of preventing a potential accident. A review of the tapes will show why this is necessary.

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Original NASA ASRS Text

Title: LAS TWR CTLR DESCRIBED RWY INCURSION AND SEPARATION LOSS; CITING CAUSAL FACTORS AS LACK OF STAFFING AND COMBINED LC POSITIONS.

Narrative: I WAS ADVISED OF A RWY INCURSION BY CTLRS AND MGMNT AT THE FACILITY. I WAS NOT WORKING DURING THE TIME OF THE OCCURRENCE. HOWEVER; I HAD THE OPPORTUNITY TO LISTEN TO THE VOICE RECORDINGS AND ASDE VIDEO PLAYBACK OF THE EVENT. IT IS MY BELIEF THAT HAVING THE 2 LCL CTL POS COMBINED (LCL CTL 2 AND LCL CTL 3) WAS A CONTRIBUTING FACTOR FOR THIS RWY INCURSION. THE VOICE TAPE DEMONSTRATES THE FREQ CONGESTION AND DISTRS THAT THE CTLR HAD TO DEAL WITH DURING THE TIME OF THE ERROR. LAS VEGAS IS UNIQUE IN THE LARGE VOLUME OF HELIS THAT OPERATE WITHIN THE CLASS B AIRSPACE. AT THE LAS VEGAS CTL TWR THE LCL CTL 2 POS IS THE POS THAT CTLS THE TFC ON THE N/S PARALLEL RWY 19L/R. LCL CTL 2 ISSUES TKOF AND LNDG CLRNCS TO THE N/S RWYS IN ADDITION TO RECEIVING COORDS FOR XING TFC FROM GND CTL; ETC. AT THE TIME OF THE INCIDENT; LCL CTL 2 WAS COMBINED WITH LCL CTL 3. LCL CTL 3 HAS THE 'FOOTPRINT' OF THE CLASS B AIRSPACE FOR LAS TWR. LCL CTL 3 WORKS ALL OF THE HELIS WITHIN THE LAS TWR AIRSPACE BELOW 3000 FT. THIS INCLUDES PRE-ASSIGNED RTES; OVERFLTS; PHOTO MISSIONS; POLICE AND LIFE-FLT HELIS; ETC. WHEN WORKING LCL CTL 3 YOU ARE REQUIRED TO RADAR IDENT TFC AND MONITOR TRANSITIONS INTO; OUT OF; AND THROUGH THE LAS VEGAS CLASS B AIRSPACE. FOR THIS REASON I SEE LCL CTL 3 AS A RADAR POS. DURING THE TIME OF THE INCIDENT LCL CTL 2 AND LCL CTL 3 WERE COMBINED. ACR X B737 DEPARTED RWY 19L WHILE ACFT Y WAS XING THE RWY. ALL NECESSARY COORD FOR THE XING WAS DONE ON A RECORDED LINE WITH THE GND CTLR AS PRESCRIBED BY THE 7110.65. THE CTLR'S MEMORY JOGGERS WERE PLACED ON THE COUNTER TOP IN ACCORDANCE WITH THE FACILITY SOP. WITH BOTH OF THESE SAFETY NETS IN PLACE; THE SYS STILL FAILED. THE CTLR'S ATTN WAS SPLIT BTWN THE RADAR SCOPE AND THE RWYS; BECAUSE HE WAS WORKING '2 DIFFERENT' POS. THE ABOVE SHOULD ILLUSTRATE THE CONFLICT WITH THE 2 POS. THE LCL CTL 2'S PRIMARY RESPONSIBILITY IS THE RWY AND SCANNING OUT THE TWR WINDOWS. WHILE LCL CTL 3'S PRIMARY RESPONSIBILITY IS THE RADAR SCOPE AND SCANNING THE AIRSPACE. THESE 2 INHERENTLY DIFFERENT POS SHOULD ONLY BE COMBINED WHEN TFC VOLUME IS AT A MINIMUM. THE COMBINING OF THESE 2 POS HAS BECOME MORE COMMON WITH THE DECREASE IN STAFFING LEVELS AT LAS VEGAS TWR. KEEPING THESE 2 POS SEPARATE IS A VITAL PART OF PREVENTING A POTENTIAL ACCIDENT. A REVIEW OF THE TAPES WILL SHOW WHY THIS IS NECESSARY.

Data retrieved from NASA's ASRS site as of January 2009 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.