Narrative:

While en route mdw to cle at FL250 we entered an area of light then moderate turbulence. We changed our altitude to FL190, however, the moderate turbulence continued. We requested a lower altitude, however, ZOB said he had traffic at 17000 ft (a DC9) which we both had in sight. Shortly we entered a brief band of severe turbulence and informed ZOB we were departing FL190 VFR (we were in VFR conditions at FL190) to escape this severe turbulence. When we reached 17000 ft the air became smooth. We continued our flight to cle with no other problems. The only problem we had was the lack of ZOB support to work our request to go down to a lower altitude. I assume the 17000 ft traffic (which we had in sight) became more of a concern than our request to escape the severe turbulence. I felt the only choice I had was to fly VFR to a lower altitude on my own separation to ensure our passenger and crew members safety. We understand his concern for traffic separation, however, when we both had each other in sight, I don't understand why center could not at least advise of each other's position 'one more time' and clear us to maneuver as required to escape the severe turbulence.

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Original NASA ASRS Text

Title: ACR FLC CHANGES ALT DUE TO TURB AFTER ATC HAD REFUSED THE ALT CHANGE.

Narrative: WHILE ENRTE MDW TO CLE AT FL250 WE ENTERED AN AREA OF LIGHT THEN MODERATE TURB. WE CHANGED OUR ALT TO FL190, HOWEVER, THE MODERATE TURB CONTINUED. WE REQUESTED A LOWER ALT, HOWEVER, ZOB SAID HE HAD TFC AT 17000 FT (A DC9) WHICH WE BOTH HAD IN SIGHT. SHORTLY WE ENTERED A BRIEF BAND OF SEVERE TURB AND INFORMED ZOB WE WERE DEPARTING FL190 VFR (WE WERE IN VFR CONDITIONS AT FL190) TO ESCAPE THIS SEVERE TURB. WHEN WE REACHED 17000 FT THE AIR BECAME SMOOTH. WE CONTINUED OUR FLT TO CLE WITH NO OTHER PROBS. THE ONLY PROB WE HAD WAS THE LACK OF ZOB SUPPORT TO WORK OUR REQUEST TO GO DOWN TO A LOWER ALT. I ASSUME THE 17000 FT TFC (WHICH WE HAD IN SIGHT) BECAME MORE OF A CONCERN THAN OUR REQUEST TO ESCAPE THE SEVERE TURB. I FELT THE ONLY CHOICE I HAD WAS TO FLY VFR TO A LOWER ALT ON MY OWN SEPARATION TO ENSURE OUR PAX AND CREW MEMBERS SAFETY. WE UNDERSTAND HIS CONCERN FOR TFC SEPARATION, HOWEVER, WHEN WE BOTH HAD EACH OTHER IN SIGHT, I DON'T UNDERSTAND WHY CTR COULD NOT AT LEAST ADVISE OF EACH OTHER'S POS 'ONE MORE TIME' AND CLR US TO MANEUVER AS REQUIRED TO ESCAPE THE SEVERE TURB.

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.