Narrative:

Air carrier X in an effort to go over a small cumulus cloud we asked chicago center if we could have FL220. (Air carrier X in cruise flight at FL200 and also cleared to deviate around local thunderstorms.) chicago cleared us up to FL220 and we began our climb. About 30 seconds to 1 min later I told center that the WX was ok to turn to fwa and we were now out of 210 for 220. He asked us to repeat our altitude and I told him 21300. He said his scope showed us level at 220 and that we had conflicting air carrier Y at 11 O'clock same altitude. We had already seen this traffic and reported clear of him. We did not have to take evasive action nor did the other aircraft. I decided after this incident to pull the circuit breaker for the cockpit voice recorder in case we needed it to prove we were never level at 220 as displayed on the screen of the ATC center. Supplemental information from acn 180989: we requested and were assigned heading 280 degree for WX avoidance. After on that heading for about 10 mi, we requested FL220. That request was also granted. I began a climb to FL220 at 1000 FPM. Passing FL213 both pilots saw an aircraft on a southeast heading passing from right to left with what appeared to be less than required separation. Then the controller asked our altitude. We replied we were passing FL213. He said he thought we were level FL220. Once level FL220 we asked for an altitude check. He showed FL221. Nothing else was said by the controller about the situation.

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Original NASA ASRS Text

Title: ACR X HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: ACR X IN AN EFFORT TO GO OVER A SMALL CUMULUS CLOUD WE ASKED CHICAGO CENTER IF WE COULD HAVE FL220. (ACR X IN CRUISE FLT AT FL200 AND ALSO CLRED TO DEVIATE AROUND LCL TSTMS.) CHICAGO CLRED US UP TO FL220 AND WE BEGAN OUR CLB. ABOUT 30 SECONDS TO 1 MIN LATER I TOLD CENTER THAT THE WX WAS OK TO TURN TO FWA AND WE WERE NOW OUT OF 210 FOR 220. HE ASKED US TO REPEAT OUR ALT AND I TOLD HIM 21300. HE SAID HIS SCOPE SHOWED US LEVEL AT 220 AND THAT WE HAD CONFLICTING ACR Y AT 11 O'CLOCK SAME ALT. WE HAD ALREADY SEEN THIS TFC AND RPTED CLR OF HIM. WE DID NOT HAVE TO TAKE EVASIVE ACTION NOR DID THE OTHER ACFT. I DECIDED AFTER THIS INCIDENT TO PULL THE CIRCUIT BREAKER FOR THE COCKPIT VOICE RECORDER IN CASE WE NEEDED IT TO PROVE WE WERE NEVER LEVEL AT 220 AS DISPLAYED ON THE SCREEN OF THE ATC CENTER. SUPPLEMENTAL INFO FROM ACN 180989: WE REQUESTED AND WERE ASSIGNED HDG 280 DEG FOR WX AVOIDANCE. AFTER ON THAT HDG FOR ABOUT 10 MI, WE REQUESTED FL220. THAT REQUEST WAS ALSO GRANTED. I BEGAN A CLB TO FL220 AT 1000 FPM. PASSING FL213 BOTH PLTS SAW AN ACFT ON A SE HDG PASSING FROM R TO L WITH WHAT APPEARED TO BE LESS THAN REQUIRED SEPARATION. THEN THE CTLR ASKED OUR ALT. WE REPLIED WE WERE PASSING FL213. HE SAID HE THOUGHT WE WERE LEVEL FL220. ONCE LEVEL FL220 WE ASKED FOR AN ALT CHK. HE SHOWED FL221. NOTHING ELSE WAS SAID BY THE CTLR ABOUT THE SITUATION.

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.