Narrative:

I was working local west (lw). I got a strip on flight abc going north. I don't recall him saying his call sign was anything different. I cleared him for take off; he acquired; and when I had appropriate separation I switched him to north departure. He read back and emphasized flight abg when I switched him even though I had called him flight abc as did his strip and his data tag. I called north departure because the pilot had already switched and asked that he verified the call sign. I then asked clearance delivery/FD if they had a flight abg. They said no. The ground controller and FD/clearance delivery controllers also thought it strange that the pilot didn't correct them. In the mean time north departure called back and verified that the pilot was intent that the call sign was flight abg and not flight abc. I then saw the data tag change. I assume the departure controller did it. We have been having a bad time with similar sounding call signs and pilots not knowing that their flight numbers have changed and now evidently we don't know they are changing either. This is getting more and more troubling and perplexing to me and several others here. Company responded to our management for an excuse of why we have so many call signs with letters and similar sounding/looking; but they never addressed why the crews don't know about their call signs changing. They need to communicate better to crews and now it may appear the agency as well. In our last weekly meeting management was going to follow up with company chief pilot on why crews don't know; but to date I haven't heard anything back.

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Original NASA ASRS Text

Title: IAH Controller experienced confusion with regard to similar sounding call signs noting the problem is becoming more serious with no resolution in sight.

Narrative: I was working Local West (LW). I got a strip on Flight ABC going north. I don't recall him saying his call sign was anything different. I cleared him for take off; he acquired; and when I had appropriate separation I switched him to North Departure. He read back and emphasized Flight ABG when I switched him even though I had called him Flight ABC as did his strip and his data tag. I called North Departure because the pilot had already switched and asked that he verified the call sign. I then asked CD/FD if they had a Flight ABG. They said no. The Ground Controller and FD/CD controllers also thought it strange that the pilot didn't correct them. In the mean time north departure called back and verified that the pilot was intent that the call sign was Flight ABG and not Flight ABC. I then saw the data tag change. I assume the Departure Controller did it. We have been having a bad time with similar sounding call signs and pilots not knowing that their flight numbers have changed and now evidently we don't know they are changing either. This is getting more and more troubling and perplexing to me and several others here. Company responded to our management for an excuse of why we have so many call signs with letters and similar sounding/looking; but they never addressed why the crews don't know about their call signs changing. They need to communicate better to crews and now it may appear the Agency as well. In our last weekly meeting Management was going to follow up with Company Chief Pilot on why crews don't know; but to date I haven't heard anything back.

Data retrieved from NASA's ASRS site as of July 2013 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.