Narrative:

We were flying north on A300 at FL350 and received a message via new york from dispatch of some WX up along our route of flight. Since there was also WX reported to our west, we decided to continue on course. About 150 mi south of champ we began to see the WX on the radar. About 100 mi south of champ, we requested and soon received a clearance to deviate 25 mi west of course for WX avoidance. We soon began to turn west of course as the line of WX appeared to end 20 mi west of A300 and was reported to be moving northeast. I informed the passenger that there was a chance that we might encounter some rough air, put on the seat belt sign and had them buckle up. I briefed the #1 flight attendant, and they stowed all the food carts, cleaned up the cabin, made one final sweep through the cabin to ensure that all the passenger were buckled in. They then strapped themselves in at their assigned jump seats. We managed to find our way around most of the bad WX, picking up a few bumps along the way. About 22 mi west of course we saw an opening on the radar back to the north. We commenced a turn to the north and were heading back towards champ when we encountered the turbulence. The aircraft deviated up to 500 ft above and 900 ft below FL350, and the airspeed varied from mach .75 to mach .84 during the climbs and dscnts. We just tried to maintain mach .80 and smooth out the altdevs. It was over in about 30 seconds, and we were immediately out in clear sky. Despite the fact that we never saw what caused all of this we were very well prepared and there were no injuries or damage to the aircraft. We notified ATC and dispatch of the WX.

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Original NASA ASRS Text

Title: B727 ACFT ENCOUNTERED TURB ENRTE WHILE DEVIATING AROUND WX RESULTING IN ALTDEVS.

Narrative: WE WERE FLYING N ON A300 AT FL350 AND RECEIVED A MESSAGE VIA NEW YORK FROM DISPATCH OF SOME WX UP ALONG OUR RTE OF FLT. SINCE THERE WAS ALSO WX RPTED TO OUR W, WE DECIDED TO CONTINUE ON COURSE. ABOUT 150 MI S OF CHAMP WE BEGAN TO SEE THE WX ON THE RADAR. ABOUT 100 MI S OF CHAMP, WE REQUESTED AND SOON RECEIVED A CLRNC TO DEVIATE 25 MI W OF COURSE FOR WX AVOIDANCE. WE SOON BEGAN TO TURN W OF COURSE AS THE LINE OF WX APPEARED TO END 20 MI W OF A300 AND WAS RPTED TO BE MOVING NE. I INFORMED THE PAX THAT THERE WAS A CHANCE THAT WE MIGHT ENCOUNTER SOME ROUGH AIR, PUT ON THE SEAT BELT SIGN AND HAD THEM BUCKLE UP. I BRIEFED THE #1 FLT ATTENDANT, AND THEY STOWED ALL THE FOOD CARTS, CLEANED UP THE CABIN, MADE ONE FINAL SWEEP THROUGH THE CABIN TO ENSURE THAT ALL THE PAX WERE BUCKLED IN. THEY THEN STRAPPED THEMSELVES IN AT THEIR ASSIGNED JUMP SEATS. WE MANAGED TO FIND OUR WAY AROUND MOST OF THE BAD WX, PICKING UP A FEW BUMPS ALONG THE WAY. ABOUT 22 MI W OF COURSE WE SAW AN OPENING ON THE RADAR BACK TO THE N. WE COMMENCED A TURN TO THE N AND WERE HEADING BACK TOWARDS CHAMP WHEN WE ENCOUNTERED THE TURB. THE ACFT DEVIATED UP TO 500 FT ABOVE AND 900 FT BELOW FL350, AND THE AIRSPD VARIED FROM MACH .75 TO MACH .84 DURING THE CLBS AND DSCNTS. WE JUST TRIED TO MAINTAIN MACH .80 AND SMOOTH OUT THE ALTDEVS. IT WAS OVER IN ABOUT 30 SECONDS, AND WE WERE IMMEDIATELY OUT IN CLR SKY. DESPITE THE FACT THAT WE NEVER SAW WHAT CAUSED ALL OF THIS WE WERE VERY WELL PREPARED AND THERE WERE NO INJURIES OR DAMAGE TO THE ACFT. WE NOTIFIED ATC AND DISPATCH OF THE WX.

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.