Narrative:

I was working south radar when aircraft X called in as a flight of 3 VFR helicopters declaring an emergency. One of them was declaring an emergency for one in his flight. I asked several times of his location he said at 500 ft. I had the helicopter squawk 7700 tuned up beacon and video and I saw nothing. I called an adjacent tower and they did; so I told them I would put the emergency on them to help him. The issue is our radar was unable to see and emergency squawking 7700; this is unacceptable and unsafe. We eventually saw the helicopter with 7700 code.

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Original NASA ASRS Text

Title: Approach Controller described emergency event when aircraft on transponder code 7700 was not visible on radar but well within range limitations and observed by adjacent radar equipment.

Narrative: I was working South Radar when Aircraft X called in as a flight of 3 VFR helicopters declaring an emergency. One of them was declaring an emergency for one in his flight. I asked several times of his location he said at 500 FT. I had the helicopter squawk 7700 tuned up beacon and video and I saw nothing. I called an adjacent tower and they did; so I told them I would put the emergency on them to help him. The issue is our radar was unable to see and emergency squawking 7700; this is unacceptable and unsafe. We eventually saw the helicopter with 7700 code.

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.