Narrative:

Taxied to runway 31C via txwys Y, P, G. Company aircraft was holding short of runway 31C on E1. Approaching company aircraft, captain taxied around aircraft to hold short next to company aircraft on E3. As we were doing so, we were told to clear runway 31R by tower. We realized we had crossed the hold short line for runway 31R. We cleared the hold short line and held short of runway 31R on E2. Mdw 10-9B page is incorrect. The hold short lines for runways 31C and 31R are not parallel. They actually converge near E3. There is no room to hold short of runway 31C on E3 and remain clear of runway 31R. Recommend changing 10-9B page to reflect actual runway markings. Supplemental information from acn 617821: we skirted the company aircraft ahead by crossing the runways 13L/31R hold short line in the vicinity of the runway 31R ILS hold short line as depicted on mdw 10-9B page where it intersects the taxiway E1. I taxied around our other aircraft in the off chance he was delayed, we would be in position for an immediate takeoff. We were aware of an aircraft on final to runway 31C which was circling to runway 31R, in vicinity of runts, an aircraft actually over the threshold to runway 31C or touching down at that time. With the lower ceilings, I mistakenly assumed runway 31R not being in use, staying clear of the actual runway 31R. Coming back through mdw later, I talked with a supervisor in the tower. He said no harm, no foul, training was in progress. He also mentioned some lines had been moved around and then mentioned spacing, size and number of aircraft that were able to be accommodated in that area. There were 2 other aircraft besides ourselves who had transgressed. Recommend note in 10-7 page and excerpts in as soon as possible occurrence letter hot spot?

Google
 

Original NASA ASRS Text

Title: RWY INCURSION WHEN THE PIC OF A TAXIING B737 CROSSES OVER WHAT HE CONSIDERED LATER TO BE MISPLACED HOLD SHORT LINES NEAR RWY 31R AT MDW.

Narrative: TAXIED TO RWY 31C VIA TXWYS Y, P, G. COMPANY ACFT WAS HOLDING SHORT OF RWY 31C ON E1. APCHING COMPANY ACFT, CAPT TAXIED AROUND ACFT TO HOLD SHORT NEXT TO COMPANY ACFT ON E3. AS WE WERE DOING SO, WE WERE TOLD TO CLR RWY 31R BY TWR. WE REALIZED WE HAD CROSSED THE HOLD SHORT LINE FOR RWY 31R. WE CLRED THE HOLD SHORT LINE AND HELD SHORT OF RWY 31R ON E2. MDW 10-9B PAGE IS INCORRECT. THE HOLD SHORT LINES FOR RWYS 31C AND 31R ARE NOT PARALLEL. THEY ACTUALLY CONVERGE NEAR E3. THERE IS NO ROOM TO HOLD SHORT OF RWY 31C ON E3 AND REMAIN CLR OF RWY 31R. RECOMMEND CHANGING 10-9B PAGE TO REFLECT ACTUAL RWY MARKINGS. SUPPLEMENTAL INFO FROM ACN 617821: WE SKIRTED THE COMPANY ACFT AHEAD BY XING THE RWYS 13L/31R HOLD SHORT LINE IN THE VICINITY OF THE RWY 31R ILS HOLD SHORT LINE AS DEPICTED ON MDW 10-9B PAGE WHERE IT INTERSECTS THE TXWY E1. I TAXIED AROUND OUR OTHER ACFT IN THE OFF CHANCE HE WAS DELAYED, WE WOULD BE IN POS FOR AN IMMEDIATE TKOF. WE WERE AWARE OF AN ACFT ON FINAL TO RWY 31C WHICH WAS CIRCLING TO RWY 31R, IN VICINITY OF RUNTS, AN ACFT ACTUALLY OVER THE THRESHOLD TO RWY 31C OR TOUCHING DOWN AT THAT TIME. WITH THE LOWER CEILINGS, I MISTAKENLY ASSUMED RWY 31R NOT BEING IN USE, STAYING CLR OF THE ACTUAL RWY 31R. COMING BACK THROUGH MDW LATER, I TALKED WITH A SUPVR IN THE TWR. HE SAID NO HARM, NO FOUL, TRAINING WAS IN PROGRESS. HE ALSO MENTIONED SOME LINES HAD BEEN MOVED AROUND AND THEN MENTIONED SPACING, SIZE AND NUMBER OF ACFT THAT WERE ABLE TO BE ACCOMMODATED IN THAT AREA. THERE WERE 2 OTHER ACFT BESIDES OURSELVES WHO HAD TRANSGRESSED. RECOMMEND NOTE IN 10-7 PAGE AND EXCERPTS IN ASAP OCCURRENCE LETTER HOT SPOT?

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.