Narrative:

On right base after reporting location, tower advised us of experimental aircraft 5 mi north of navy key west for right base to runway 27. Then tower also advised that we were in sight, #1 for runway 27 and cleared to land. Descending on base experimental aircraft appeared at our 5 O'clock position approximately 20 ft. We descended through his flight path. Later on, a telephone conversation between our first officer (me) and tower supervisor, supervisor said that experimental aircraft failed to report base as directed. No evasive actions were available.

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Original NASA ASRS Text

Title: NMAC BTWN AN ACR LTT AND AN EXPERIMENTAL ACFT IN THE ATA ON A BASE LEG.

Narrative: ON R BASE AFTER RPTING LOCATION, TWR ADVISED US OF EXPERIMENTAL ACFT 5 MI N OF NAVY KEY WEST FOR R BASE TO RWY 27. THEN TWR ALSO ADVISED THAT WE WERE IN SIGHT, #1 FOR RWY 27 AND CLRED TO LAND. DSNDING ON BASE EXPERIMENTAL ACFT APPEARED AT OUR 5 O'CLOCK POS APPROX 20 FT. WE DSNDED THROUGH HIS FLT PATH. LATER ON, A TELEPHONE CONVERSATION BTWN OUR FO (ME) AND TWR SUPVR, SUPVR SAID THAT EXPERIMENTAL ACFT FAILED TO RPT BASE AS DIRECTED. NO EVASIVE ACTIONS WERE AVAILABLE.

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.