Narrative:

On frequency 128.5 given FL210. When center switched frequency they stated unable FL230, frequency 128.2 knows requested altitude FL230. Crew checkin 128.2. Flight hfb climbing to FL210. Center acknowledge. Center's next transmission hfb fly heading 100 degree for traffic flow. Roger hfb, 100 degree. Center then called a company B flight and stated unable FL230. Company B acknowledge. Flight hfb then requested several times for a vector to avoid WX. No center acknowledgement. When flight hfb broke out of clouds, flight hfb requesting FL230. Center answered then paused, then asked what altitude are you at. Flight hfb stated FL210 and requesting FL230. Center then stated I gave you FL200. Flight hfb stated no you did not Y9U must have been talking to other company B. Center then said no it was you, descend and maintain FL200 in less than 1 minute. Flight hfb then descended to FL200. No further conflicts noted by flight crew. It is my belief that center was overloaded due to WX in the byson gate area and that led to confusion of aircraft and flight altitudes. Possibly an increase in center manpwr during thunderstorm periods would help with aircraft and WX related problems.

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Original NASA ASRS Text

Title: MLG FLT CREW CLIMBED TO ASSIGNED ALT. REQUESTED FL230 SEVERAL TIMES AS DID ANOTHER ACR. CENTER STATED UNABLE TO BOTH. ON HANDOFF CTLR QUESTIONED ALT THEN SAID ASSIGNED WAS FL200 AND DESCEND NOW.

Narrative: ON FREQ 128.5 GIVEN FL210. WHEN CENTER SWITCHED FREQ THEY STATED UNABLE FL230, FREQ 128.2 KNOWS REQUESTED ALT FL230. CREW CHECKIN 128.2. FLT HFB CLIMBING TO FL210. CENTER ACKNOWLEDGE. CENTER'S NEXT XMISSION HFB FLY HDG 100 DEG FOR TFC FLOW. ROGER HFB, 100 DEG. CENTER THEN CALLED A COMPANY B FLT AND STATED UNABLE FL230. COMPANY B ACKNOWLEDGE. FLT HFB THEN REQUESTED SEVERAL TIMES FOR A VECTOR TO AVOID WX. NO CENTER ACKNOWLEDGEMENT. WHEN FLT HFB BROKE OUT OF CLOUDS, FLT HFB REQUESTING FL230. CENTER ANSWERED THEN PAUSED, THEN ASKED WHAT ALT ARE YOU AT. FLT HFB STATED FL210 AND REQUESTING FL230. CENTER THEN STATED I GAVE YOU FL200. FLT HFB STATED NO YOU DID NOT Y9U MUST HAVE BEEN TALKING TO OTHER COMPANY B. CENTER THEN SAID NO IT WAS YOU, DSND AND MAINTAIN FL200 IN LESS THAN 1 MINUTE. FLT HFB THEN DESCENDED TO FL200. NO FURTHER CONFLICTS NOTED BY FLT CREW. IT IS MY BELIEF THAT CENTER WAS OVERLOADED DUE TO WX IN THE BYSON GATE AREA AND THAT LED TO CONFUSION OF ACFT AND FLT ALTS. POSSIBLY AN INCREASE IN CENTER MANPWR DURING TSTM PERIODS WOULD HELP WITH ACFT AND WX RELATED PROBLEMS.

Data retrieved from NASA's ASRS site as of August 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.