Narrative:

After a 50 minute taxi to runway 36R; the clt tower controller instructed us to taxi into position and hold for wake turbulence for departing heavy 767; additional traffic on a 7 mile final. I started time as soon as the 767 began his roll and we taxied into position. At approximately 1 minute and 35 seconds the tower cleared us for takeoff. We instructed the tower that we needed 15 more seconds for wake separation (and that was at 1 minute 45 seconds). Tower then instructed us to expedite off the runway on C2 intersection. This seemed like a silly request because it was going to take as much time to clear the runway as to wait the 15 seconds and then take off. But we did not argue and taxied to C2 intersection where we could not clear the runway because of another taxiing aircraft on taxiway C. Lucky enough for us; the aircraft was listening; had just enough space where he could do a 360 degree turn; and the next aircraft in line had not pulled right up behind him. So all this happened; then we finally cleared the runway just as the arriving aircraft came over the runway threshold. After we were all situated; I asked the controller if it was standard to provide a 2 minute separation for heavy aircraft. He didn't answer; so I asked again. He replied that the departing aircraft was 7 miles away from the field so wake was not a factor. From what I understand (on wake turbulence separation for departing aircraft) is that separation is to be based on time (2 minutes separation); not distance for 757's and heavies. The event occurred because the controller believes wake turbulence is based off of distance; and the fact that I thought it was not safe to take off under that condition. Secondly; I believe the next decision he made was the wrong one by taxiing us off the runway instead of waiting the 15 seconds and then letting us take off. However; this (I'm sure) is debatable.

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Original NASA ASRS Text

Title: Air carrier departure from CLT questioned ATC's wake turbulence separation; was directed to clear the runway for arrival traffic.

Narrative: After a 50 minute taxi to Runway 36R; the CLT Tower Controller instructed us to taxi into position and hold for wake turbulence for departing heavy 767; additional traffic on a 7 mile final. I started time as soon as the 767 began his roll and we taxied into position. At approximately 1 minute and 35 seconds the Tower cleared us for takeoff. We instructed the Tower that we needed 15 more seconds for wake separation (and that was at 1 minute 45 seconds). Tower then instructed us to expedite off the runway on C2 Intersection. This seemed like a silly request because it was going to take as much time to clear the runway as to wait the 15 seconds and then take off. But we did not argue and taxied to C2 Intersection where we could not clear the runway because of another taxiing aircraft on Taxiway C. Lucky enough for us; the aircraft was listening; had just enough space where he could do a 360 degree turn; and the next aircraft in line had not pulled right up behind him. So all this happened; then we finally cleared the runway just as the arriving aircraft came over the runway threshold. After we were all situated; I asked the Controller if it was standard to provide a 2 minute separation for heavy aircraft. He didn't answer; so I asked again. He replied that the departing aircraft was 7 miles away from the field so wake was not a factor. From what I understand (on wake turbulence separation for departing aircraft) is that separation is to be based on time (2 minutes separation); not distance for 757's and heavies. The event occurred because the Controller believes wake turbulence is based off of distance; and the fact that I thought it was not safe to take off under that condition. Secondly; I believe the next decision he made was the wrong one by taxiing us off the runway instead of waiting the 15 seconds and then letting us take off. However; this (I'm sure) is debatable.

Data retrieved from NASA's ASRS site as of April 2012 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.