Narrative:

Flight began from concord, nc (jqf) and was returning to navy jax (nip). The flight was VFR at 16500 ft. At approximately 50 mi north of jax, I began a descent to 3500 ft as assigned by jax approach. At a point approximately 4 mi due east of jax, I noticed 2 aircraft in an area of 1-2 O'clock position. I was advised by ATC to maintain VFR at 3500 ft. I had these 2 aircraft on TCASII with no TCASII alert at any time. I maneuvered my aircraft to maintain VFR and traffic avoidance and descended (unnoticed by me) to approximately 3300 ft while looking for the traffic and avoiding clouds. The traffic was an air carrier rj departing jax and fellow company traffic also en route to nip. The rj stated over the radio to ATC that he had deviated for traffic within 300 ft. We saw this traffic and at no time did we receive a TA from the rj. I did continue sbound towards nip and at one point had descended to approximately 3000 ft while maneuvering for clouds and looking for traffic. Once I realized my altitude error, I immediately corrected. The lower altitude was well after the aforementioned incident. My aircraft had a crew of 3 and the aircraft is TCASII equipped and has an onboard radar that is capable of sorting traffic. (The TCASII radar is the same radar used on the F-16). At no time was the crew alerted by the rj until he announced his flight path deviation. The flight terminated at nip without incident.

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Original NASA ASRS Text

Title: P-3 CREW HAD AN ALT OVERSHOOT IN JAX CLASS C AIRSPACE.

Narrative: FLT BEGAN FROM CONCORD, NC (JQF) AND WAS RETURNING TO NAVY JAX (NIP). THE FLT WAS VFR AT 16500 FT. AT APPROX 50 MI N OF JAX, I BEGAN A DSCNT TO 3500 FT AS ASSIGNED BY JAX APCH. AT A POINT APPROX 4 MI DUE E OF JAX, I NOTICED 2 ACFT IN AN AREA OF 1-2 O'CLOCK POS. I WAS ADVISED BY ATC TO MAINTAIN VFR AT 3500 FT. I HAD THESE 2 ACFT ON TCASII WITH NO TCASII ALERT AT ANY TIME. I MANEUVERED MY ACFT TO MAINTAIN VFR AND TFC AVOIDANCE AND DSNDED (UNNOTICED BY ME) TO APPROX 3300 FT WHILE LOOKING FOR THE TFC AND AVOIDING CLOUDS. THE TFC WAS AN ACR RJ DEPARTING JAX AND FELLOW COMPANY TFC ALSO ENRTE TO NIP. THE RJ STATED OVER THE RADIO TO ATC THAT HE HAD DEVIATED FOR TFC WITHIN 300 FT. WE SAW THIS TFC AND AT NO TIME DID WE RECEIVE A TA FROM THE RJ. I DID CONTINUE SBOUND TOWARDS NIP AND AT ONE POINT HAD DSNDED TO APPROX 3000 FT WHILE MANEUVERING FOR CLOUDS AND LOOKING FOR TFC. ONCE I REALIZED MY ALT ERROR, I IMMEDIATELY CORRECTED. THE LOWER ALT WAS WELL AFTER THE AFOREMENTIONED INCIDENT. MY ACFT HAD A CREW OF 3 AND THE ACFT IS TCASII EQUIPPED AND HAS AN ONBOARD RADAR THAT IS CAPABLE OF SORTING TFC. (THE TCASII RADAR IS THE SAME RADAR USED ON THE F-16). AT NO TIME WAS THE CREW ALERTED BY THE RJ UNTIL HE ANNOUNCED HIS FLT PATH DEV. THE FLT TERMINATED AT NIP WITHOUT INCIDENT.

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.