Narrative:

We had aircraft X; aircraft Y; and aircraft Z in the pattern on the same runway. I believe this is a safety hazard because of their similar sounding call signs; compounded with the lack of english proficiency from the student pilots. It happened because the flight school on base does not appear to want to comply with our repeated request to put so many aircraft with similar sounding call signs in the pattern. Management met with the school and asked them [to] schedule different times when their aircraft with similar sounding call signs [would] do pattern work. They said they would honor our request; [but] 10 days later this incident occurred. Bottom line; they must cooperate for this to work.

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Original NASA ASRS Text

Title: Tower Controller voiced concern regarding a local flight school practice that launches several aircraft for pattern work with very similar call signs; complicated by student language limitations.

Narrative: We had Aircraft X; Aircraft Y; and Aircraft Z in the pattern on the same runway. I believe this is a safety hazard because of their similar sounding call signs; compounded with the lack of English proficiency from the student pilots. It happened because the flight school on base does not appear to want to comply with our repeated request to put so many aircraft with similar sounding call signs in the pattern. Management met with the school and asked them [to] schedule different times when their aircraft with similar sounding call signs [would] do pattern work. They said they would honor our request; [but] 10 days later this incident occurred. Bottom line; they must cooperate for this to work.

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.