Narrative:

Departed mtn airport for an instrument training flight with a cfii candidate to mrb. After contacting bwi approach we were assigned 6000 ft. En route climb proceeded normally. Passing through 5300 ft, controller queried our altitude. Student replied, 5300 ft, and controller indicated mode C altitude showed 2200 ft. Controller assigned a new altitude of 5000 ft. I then observed traffic at 1 O'clock and approach confirmed an airbus at 6000 ft. We descended immediately to 5000 ft. Initial controller appeared to be a trainee. The second controller who came on frequency resolved conflict.

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Original NASA ASRS Text

Title: AN INSTRUCTOR AND HIS STUDENT WERE TOLD TO LEVEL AT AN INTERMEDIATE ALT TO AVOID A CONFLICT WITH HIGHER TFC.

Narrative: DEPARTED MTN ARPT FOR AN INST TRAINING FLT WITH A CFII CANDIDATE TO MRB. AFTER CONTACTING BWI APCH WE WERE ASSIGNED 6000 FT. ENRTE CLB PROCEEDED NORMALLY. PASSING THROUGH 5300 FT, CTLR QUERIED OUR ALT. STUDENT REPLIED, 5300 FT, AND CTLR INDICATED MODE C ALT SHOWED 2200 FT. CTLR ASSIGNED A NEW ALT OF 5000 FT. I THEN OBSERVED TFC AT 1 O'CLOCK AND APCH CONFIRMED AN AIRBUS AT 6000 FT. WE DSNDED IMMEDIATELY TO 5000 FT. INITIAL CTLR APPEARED TO BE A TRAINEE. THE SECOND CTLR WHO CAME ON FREQ RESOLVED CONFLICT.

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.