Narrative:

Air carrier abcd and company air carrier abed were both on approach to runway xxl and runway yyr; both on frequency at the same time. A cautionary advisory was given to the trailing aircraft. [Same company's flights] efgh and efih were consecutive arrivals; no cautionary advisories were given to the pilots. Fortunately there were no hear back/read back errors in either of these instances. But since both aircraft were on approach and on tower frequency at the same time; it would have been easy for one aircraft to take a landing clearance or runways crossing instruction intended for the other. This company has known for a long time about similar-sounding call signs here and their potential impact on operations.

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Original NASA ASRS Text

Title: Tower Controller voiced concern regarding the continued use of similar sounding call signs by one company even after the company was notified of the potential safety factor.

Narrative: Air Carrier ABCD and Company Air Carrier ABED were both on approach to Runway XXL and Runway YYR; both on frequency at the same time. A cautionary advisory was given to the trailing aircraft. [Same Company's flights] EFGH and EFIH were consecutive arrivals; no cautionary advisories were given to the pilots. Fortunately there were no hear back/read back errors in either of these instances. But since both aircraft were on approach and on Tower frequency at the same time; it would have been easy for one aircraft to take a landing clearance or runways crossing instruction intended for the other. This Company has known for a long time about similar-sounding call signs here and their potential impact on operations.

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.