Narrative:

At 2500' MSL after a vector from departure control we received a traffic notice of 10 O'clock and 1 mi. Traffic reported that they had us in sight. One min after that we had the traffic in sight. 1 min later, we received a clearance to resume our own navigation. We took this to mean that a change in altitude and heading had been approved. Therefore, we changed our original assigned heading of 040 degree and climbed to 3000' MSL. 2 mins later departure asked us what our altitude was. We told them 3000'. The controller came back and said that we were absolutely not cleared to 3000'. Pilot controller glossary: resume own navigation. It is issued after completion of a radar vector or when radar contact is lost while aircraft is being radar vectored. We took this to mean that a change in heading and altitude was approved. Supplemental information from acn 153287. We tried to terminate radar services because we were not sure of the position of traffic (negative contact), so we could climb to 3000' MSL. By time A20 departure called us and said they show us at 3000' MSL we spotted traffic and told them we were unable to terminate radar services in time. The instrument and I were both a little confused on what exactly 'resume own navigation' meant. We thought it could also mean to climb or descend at pilot's discretion.

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Original NASA ASRS Text

Title: CFI AND STUDENT DEP AZO ARE TOLD TO RESUME THEIR OWN NAVIGATION, WHICH THEY TAKE AS MEANING THAT THEY CAN NOW ALSO CHANGE THEIR ALT.

Narrative: AT 2500' MSL AFTER A VECTOR FROM DEP CTL WE RECEIVED A TFC NOTICE OF 10 O'CLOCK AND 1 MI. TFC RPTED THAT THEY HAD US IN SIGHT. ONE MIN AFTER THAT WE HAD THE TFC IN SIGHT. 1 MIN LATER, WE RECEIVED A CLRNC TO RESUME OUR OWN NAV. WE TOOK THIS TO MEAN THAT A CHANGE IN ALT AND HDG HAD BEEN APPROVED. THEREFORE, WE CHANGED OUR ORIGINAL ASSIGNED HDG OF 040 DEG AND CLBED TO 3000' MSL. 2 MINS LATER DEP ASKED US WHAT OUR ALT WAS. WE TOLD THEM 3000'. THE CTLR CAME BACK AND SAID THAT WE WERE ABSOLUTELY NOT CLRED TO 3000'. PLT CTLR GLOSSARY: RESUME OWN NAV. IT IS ISSUED AFTER COMPLETION OF A RADAR VECTOR OR WHEN RADAR CONTACT IS LOST WHILE ACFT IS BEING RADAR VECTORED. WE TOOK THIS TO MEAN THAT A CHANGE IN HDG AND ALT WAS APPROVED. SUPPLEMENTAL INFO FROM ACN 153287. WE TRIED TO TERMINATE RADAR SVCS BECAUSE WE WERE NOT SURE OF THE POS OF TFC (NEGATIVE CONTACT), SO WE COULD CLB TO 3000' MSL. BY TIME A20 DEP CALLED US AND SAID THEY SHOW US AT 3000' MSL WE SPOTTED TFC AND TOLD THEM WE WERE UNABLE TO TERMINATE RADAR SVCS IN TIME. THE INSTR AND I WERE BOTH A LITTLE CONFUSED ON WHAT EXACTLY 'RESUME OWN NAV' MEANT. WE THOUGHT IT COULD ALSO MEAN TO CLB OR DSND AT PLT'S DISCRETION.

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.