Narrative:

Aircraft X given clearance from FL280 to FL260. At 13 mi, they got an RA to climb back up. In this case, TCASII was very effective because the pilots were looking farther out than usual and separation was reestablished with vertical spacing before horizontal was lost.

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Original NASA ASRS Text

Title: ZME CTLR DESCRIBES A NEAR LOSS OF SEPARATION SAVED BY TCASII AT FL270.

Narrative: ACFT X GIVEN CLRNC FROM FL280 TO FL260. AT 13 MI, THEY GOT AN RA TO CLB BACK UP. IN THIS CASE, TCASII WAS VERY EFFECTIVE BECAUSE THE PLTS WERE LOOKING FARTHER OUT THAN USUAL AND SEPARATION WAS REESTABLISHED WITH VERT SPACING BEFORE HORIZ WAS LOST.

Data retrieved from NASA's ASRS site as of July 2007 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.