Narrative:

I was working a 3 aircraft sequence for visual approach in to psp. #1 in sequence was a [aircraft X] and was cleared for the visual approach runway 31L. #2 was a [aircraft Y] and had the [aircraft X] in sight and was cleared for the visual approach runway 31L to follow. #3 was a [aircraft Z]; I advised position of traffic as 1-2 o'clock 7 miles. [Aircraft Y] at 4;000 feet; the crew [of [aircraft Z]] advised traffic in sight and I then cleared them to follow the regional jet to the same runway; cleared visual approach runway 31L. After a bit of time I realized the [aircraft Z] was closing in rather close to [aircraft Y] and inquired to verify he had [aircraft Y] in sight at 1130 and a mile and a half at his altitude; he responded; we do now and we will widen it out a bit here. I then instructed [aircraft Z] to maintain visual separation. Nothing procedurally need be changed. Perhaps on my part; I should be more aware of the possibility of seeing the wrong aircraft. The question I would have for the [aircraft Z] crew would be; what was your TCAS telling you with an aircraft that close and approach not telling you about it?

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Original NASA ASRS Text

Title: SCT Controller described clearing three aircraft for visual approaches to Runway 31L at PSP and to follow each other. The aircraft third in line; loses track of the second aircraft and comes within 1.5 miles before the Controller intercedes. The Controller wonders what the third aircrafts crew was seeing on their TCAS.

Narrative: I was working a 3 aircraft sequence for visual approach in to PSP. #1 in sequence was a [Aircraft X] and was cleared for the visual approach Runway 31L. #2 was a [Aircraft Y] and had the [Aircraft X] in sight and was cleared for the visual approach Runway 31L to follow. #3 was a [Aircraft Z]; I advised position of traffic as 1-2 o'clock 7 miles. [Aircraft Y] at 4;000 feet; the crew [of [Aircraft Z]] advised traffic in sight and I then cleared them to follow the regional jet to the same runway; cleared visual approach Runway 31L. After a bit of time I realized the [Aircraft Z] was closing in rather close to [Aircraft Y] and inquired to verify he had [Aircraft Y] in sight at 1130 and a mile and a half at his altitude; he responded; we do now and we will widen it out a bit here. I then instructed [Aircraft Z] to maintain visual separation. Nothing procedurally need be changed. Perhaps on my part; I should be more aware of the possibility of seeing the wrong aircraft. The question I would have for the [Aircraft Z] crew would be; what was your TCAS telling you with an aircraft that close and approach not telling you about it?

Data retrieved from NASA's ASRS site 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.