Narrative:

Aircraft performing maneuvers at altitudes greater than 1500' AGL was obviously not in contact with ATC and failure of controller to notify me made a potentially unsafe environment for flight. First noticed us entering outer area of arsa (20 NM). Question radar coverage at that altitude of lower aircraft that was doing loops. Callback conversation with reporter revealed the following: reporter advised a high wing small aircraft. He had just contacted approach controller and was surprised the controller did not report the traffic. Advised the reporter the small aircraft was probably not using transponder and because of the low altitude was not showing on the controller radar. Gave his position as much closer to the arsa than indicated in the report, 10 mi southeast of the lit VOR. No evasive action was taken and did not discuss with controller or FAA.

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Original NASA ASRS Text

Title: POTENTIAL CONFLICT WITH ACFT OPERATING VFR PERFORMING AEROBATIC MANEUVERS. SEE AND AVOID CONCEPT.

Narrative: ACFT PERFORMING MANEUVERS AT ALTS GREATER THAN 1500' AGL WAS OBVIOUSLY NOT IN CONTACT WITH ATC AND FAILURE OF CTLR TO NOTIFY ME MADE A POTENTIALLY UNSAFE ENVIRONMENT FOR FLT. FIRST NOTICED US ENTERING OUTER AREA OF ARSA (20 NM). QUESTION RADAR COVERAGE AT THAT ALT OF LOWER ACFT THAT WAS DOING LOOPS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR ADVISED A HIGH WING SMA. HE HAD JUST CONTACTED APCH CTLR AND WAS SURPRISED THE CTLR DID NOT RPT THE TFC. ADVISED THE RPTR THE SMA WAS PROBABLY NOT USING TRANSPONDER AND BECAUSE OF THE LOW ALT WAS NOT SHOWING ON THE CTLR RADAR. GAVE HIS POSITION AS MUCH CLOSER TO THE ARSA THAN INDICATED IN THE RPT, 10 MI SE OF THE LIT VOR. NO EVASIVE ACTION WAS TAKEN AND DID NOT DISCUSS WITH CTLR OR FAA.

Data retrieved from NASA's ASRS site as of August 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.