Narrative:

Due to construction on runway 19L, the full length distance was 8100 ft. We were cleared onto runway 19L at taxiway K1 to back taxi 600 ft for full length. The temporary displaced threshold was very close and appeared to be less than 600 ft to taxiway K1. We passed the mark onto the temporary stopway in order to complete a 180 degree turn. Takeoff was started from the temporary displaced threshold mark.

Google
 

Original NASA ASRS Text

Title: B767 CREW WAS UNABLE TO USE THE FULL LENGTH OF RWY 19L AT IAD BECAUSE OF RWY CONSTRUCTION.

Narrative: DUE TO CONSTRUCTION ON RWY 19L, THE FULL LENGTH DISTANCE WAS 8100 FT. WE WERE CLRED ONTO RWY 19L AT TXWY K1 TO BACK TAXI 600 FT FOR FULL LENGTH. THE TEMPORARY DISPLACED THRESHOLD WAS VERY CLOSE AND APPEARED TO BE LESS THAN 600 FT TO TXWY K1. WE PASSED THE MARK ONTO THE TEMPORARY STOPWAY IN ORDER TO COMPLETE A 180 DEG TURN. TKOF WAS STARTED FROM THE TEMPORARY DISPLACED THRESHOLD MARK.

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.