Narrative:

On vectors for visual approach to hunter aaf (svn) runway 10. Numerous thunderstorm and heavy localized rain all around. Cleared to descend to 3000 ft. At approximately 3300 ft descending, approach asked us to confirm our altitude was level at 3300 ft. Traffic was reported west of our position (our heading was 170 degrees), military fighters. We climbed back to 3500 ft and visually acquired traffic as it passed 1000 ft below us. ATC was very busy trying to handle VFR light aircraft that could not comply with ATC instructions due to numerous WX cells nearby. It seemed to our crew that ATC was very frustrated with the VFR aircraft and may have become saturated. We feel strongly that, as a crew, we heard and acknowledged a clearance to descend to 3000 ft. As an aside, after we had requested a lower altitude to obtain visual contact with ksvn, we were cleared to 2000 ft. As we were leveling 2000 ft, we were then instructed to climb back to 2500 ft. This was due to VFR cessna previously discussed within approximately 2 mi of our aircraft at a similar altitude. We don't believe we were mistaken in our actions in the descent to 3000 ft to which we believe we were cleared. Coupled with the later clearance to climb back to 2500 ft after clearance to 2000 ft, I believe ATC was so concerned with the VFR aircraft and its inability to comply with instructions, coupled with numerous thunderstorm and the limited airspace in which to safely maneuver aircraft, both IFR and VFR, that they were unable to maintain total situational awareness. Again, no conflict occurred with the military fighters, as far as TCASII was concerned, and we did visually acquire them.

Related reports:

Google
 

Original NASA ASRS Text

Title: A B-757 FLT CREW THOUGHT THEY WERE CLRED TO 3000 FT BUT THE APCH CTLR THOUGHT HE ISSUED 3500 FT.

Narrative: ON VECTORS FOR VISUAL APCH TO HUNTER AAF (SVN) RWY 10. NUMEROUS TSTM AND HVY LOCALIZED RAIN ALL AROUND. CLRED TO DSND TO 3000 FT. AT APPROX 3300 FT DSNDING, APCH ASKED US TO CONFIRM OUR ALT WAS LEVEL AT 3300 FT. TFC WAS RPTED W OF OUR POS (OUR HDG WAS 170 DEGS), MIL FIGHTERS. WE CLBED BACK TO 3500 FT AND VISUALLY ACQUIRED TFC AS IT PASSED 1000 FT BELOW US. ATC WAS VERY BUSY TRYING TO HANDLE VFR LIGHT ACFT THAT COULD NOT COMPLY WITH ATC INSTRUCTIONS DUE TO NUMEROUS WX CELLS NEARBY. IT SEEMED TO OUR CREW THAT ATC WAS VERY FRUSTRATED WITH THE VFR ACFT AND MAY HAVE BECOME SATURATED. WE FEEL STRONGLY THAT, AS A CREW, WE HEARD AND ACKNOWLEDGED A CLRNC TO DSND TO 3000 FT. AS AN ASIDE, AFTER WE HAD REQUESTED A LOWER ALT TO OBTAIN VISUAL CONTACT WITH KSVN, WE WERE CLRED TO 2000 FT. AS WE WERE LEVELING 2000 FT, WE WERE THEN INSTRUCTED TO CLB BACK TO 2500 FT. THIS WAS DUE TO VFR CESSNA PREVIOUSLY DISCUSSED WITHIN APPROX 2 MI OF OUR ACFT AT A SIMILAR ALT. WE DON'T BELIEVE WE WERE MISTAKEN IN OUR ACTIONS IN THE DSCNT TO 3000 FT TO WHICH WE BELIEVE WE WERE CLRED. COUPLED WITH THE LATER CLRNC TO CLB BACK TO 2500 FT AFTER CLRNC TO 2000 FT, I BELIEVE ATC WAS SO CONCERNED WITH THE VFR ACFT AND ITS INABILITY TO COMPLY WITH INSTRUCTIONS, COUPLED WITH NUMEROUS TSTM AND THE LIMITED AIRSPACE IN WHICH TO SAFELY MANEUVER ACFT, BOTH IFR AND VFR, THAT THEY WERE UNABLE TO MAINTAIN TOTAL SITUATIONAL AWARENESS. AGAIN, NO CONFLICT OCCURRED WITH THE MIL FIGHTERS, AS FAR AS TCASII WAS CONCERNED, AND WE DID VISUALLY ACQUIRE THEM.

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.