Narrative:

After being cleared to climb to 10000 ft direct buf, syr ATC apprised me of a B757 descending out of 11000 ft opposite direction. I called traffic in sight and was then directed to descend to 9000 ft. My altitude encoder was intermittent, showing erroneous altitudes and I was asked to stop altitude squawk. Upon leveling at 9000 ft, the B757 passed well off my left wing, however, at the same time a DC9 passed dangerously close off my right wing, also opposite direction. I queried ATC about the close proximity of aircraft and let them know it was too close for my taste. The air carrier DC9 asked what altitude I was at and confirmed the separation was much too close. ATC never replied regarding either of our altitudes or proximity. ATC then handed me off to roc approach control who asked what altitude I was at. I confirmed level 9000 ft. Upon reaching buf I was asked to phone syr tower, who prior to reviewing the tapes, in so many words accused me of pilot deviation. I firmly believe that is not the case. The wrong altitude assignment was suspect to me, however, I thought it was related to the descending B757 and found myself in conflict with the DC9. A faulty mode C was a contributing factor.

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Original NASA ASRS Text

Title: A CORPORATE SMT CLBING OUT OF SYR TO 10000 FT WAS TOLD TO DSND TO 9000 FT AND TURN OFF HIS MODE C READOUT AS IT WAS INACCURATE. THE SYR CTLR GAVE THE SMT TFC INFO ON A B757 DSNDING TO 11000 FT AND THEN UPON REACHING 9000 FT THE SMT SAW A DC9 PASS OFF HIS R WING, OPPOSITE DIRECTION AT THE SAME ALT.

Narrative: AFTER BEING CLRED TO CLB TO 10000 FT DIRECT BUF, SYR ATC APPRISED ME OF A B757 DSNDING OUT OF 11000 FT OPPOSITE DIRECTION. I CALLED TFC IN SIGHT AND WAS THEN DIRECTED TO DSND TO 9000 FT. MY ALT ENCODER WAS INTERMITTENT, SHOWING ERRONEOUS ALTS AND I WAS ASKED TO STOP ALT SQUAWK. UPON LEVELING AT 9000 FT, THE B757 PASSED WELL OFF MY L WING, HOWEVER, AT THE SAME TIME A DC9 PASSED DANGEROUSLY CLOSE OFF MY R WING, ALSO OPPOSITE DIRECTION. I QUERIED ATC ABOUT THE CLOSE PROX OF ACFT AND LET THEM KNOW IT WAS TOO CLOSE FOR MY TASTE. THE ACR DC9 ASKED WHAT ALT I WAS AT AND CONFIRMED THE SEPARATION WAS MUCH TOO CLOSE. ATC NEVER REPLIED REGARDING EITHER OF OUR ALTS OR PROX. ATC THEN HANDED ME OFF TO ROC APCH CTL WHO ASKED WHAT ALT I WAS AT. I CONFIRMED LEVEL 9000 FT. UPON REACHING BUF I WAS ASKED TO PHONE SYR TWR, WHO PRIOR TO REVIEWING THE TAPES, IN SO MANY WORDS ACCUSED ME OF PLTDEV. I FIRMLY BELIEVE THAT IS NOT THE CASE. THE WRONG ALT ASSIGNMENT WAS SUSPECT TO ME, HOWEVER, I THOUGHT IT WAS RELATED TO THE DSNDING B757 AND FOUND MYSELF IN CONFLICT WITH THE DC9. A FAULTY MODE C WAS A CONTRIBUTING FACTOR.

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.