Narrative:

Flight was regularly scheduled passenger flight from iah to lafayette. Initial clearance was direct to beaumont. Thunderstorms were active in the area and ATC informed us that the route to beaumont appeared to be clear of the WX. After departure, our radar showed 2 large cells, both contouring, to the left and right of our course. The area between the cells was painting as light rain and visually showed no lightning. Upon entering the area, the aircraft encountered severe to extreme turbulence and severe, large hail. As per the aircraft flight manual 'flying in severe turbulence,' attention was given to maintaining aircraft attitude, keeping the engines spooled up (approximately 85% N1), and not making any abrupt power changes. As a result of the turbulence, the aircraft went 400' above our assigned altitude of 15000'. The recovering back to 15000' was slow, due to the need to maintain both turbulence penetration airspeed and a minimum power setting on the engines. I believe this incident was caused by the inability of our radar and ATC radar to paint dry hail. Also, there was no doppler radar available to indicate the turbulence.

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Original NASA ASRS Text

Title: MLG FLT ENCOUNTERED DRY HAIL NOT SHOWN ON ACFT RADAR OR DEP CTLR RADAR.

Narrative: FLT WAS REGULARLY SCHEDULED PAX FLT FROM IAH TO LAFAYETTE. INITIAL CLRNC WAS DIRECT TO BEAUMONT. TSTMS WERE ACTIVE IN THE AREA AND ATC INFORMED US THAT THE RTE TO BEAUMONT APPEARED TO BE CLR OF THE WX. AFTER DEP, OUR RADAR SHOWED 2 LARGE CELLS, BOTH CONTOURING, TO THE LEFT AND RIGHT OF OUR COURSE. THE AREA BTWN THE CELLS WAS PAINTING AS LIGHT RAIN AND VISUALLY SHOWED NO LIGHTNING. UPON ENTERING THE AREA, THE ACFT ENCOUNTERED SEVERE TO EXTREME TURB AND SEVERE, LARGE HAIL. AS PER THE ACFT FLT MANUAL 'FLYING IN SEVERE TURB,' ATTN WAS GIVEN TO MAINTAINING ACFT ATTITUDE, KEEPING THE ENGS SPOOLED UP (APPROX 85% N1), AND NOT MAKING ANY ABRUPT PWR CHANGES. AS A RESULT OF THE TURB, THE ACFT WENT 400' ABOVE OUR ASSIGNED ALT OF 15000'. THE RECOVERING BACK TO 15000' WAS SLOW, DUE TO THE NEED TO MAINTAIN BOTH TURB PENETRATION AIRSPD AND A MINIMUM PWR SETTING ON THE ENGS. I BELIEVE THIS INCIDENT WAS CAUSED BY THE INABILITY OF OUR RADAR AND ATC RADAR TO PAINT DRY HAIL. ALSO, THERE WAS NO DOPPLER RADAR AVAILABLE TO INDICATE THE 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.