Cabin attendants on B757-200 injured when aircraft encountered severe jolt of turbulence.

Attributes
ACN	403436
Time
Date	199805
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : per
State Reference	OK
Altitude	msl bound lower : 39000 msl bound upper : 39000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zkc
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	cruise other other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 195 flight time total : 15000 flight time type : 3000
ASRS Report	403436
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 18200 flight time type : 2010
ASRS Report	403022
Events
Anomaly	inflight encounter : weather other anomaly other
Independent Detector	other flight crewa other other : unspecified
Resolutory Action	none taken : insufficient time other
Consequence	other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other

Narrative:

In and out of clouds, the captain illuminated the seat belt sign and made appropriate PA. The only returns on radar were approximately 60 mi north. Light chop developed, which rapidly escalated to moderate to severe and culminated in one especially severe jolt. Just before the severe jolt, in and out of cirrus, I saw a build-up slightly off to the right. This was not showing on radar. We reported severe turbulence to ATC and diverted to okc after cabin crew reported injuries. Descent, approach, and landing were normal with aircraft handling normal. 4 flight attendants injured. There was just light chop being reported in the general area. There were no returns within 60 degrees of the nose. Every tool and cues didn't give us any indication that we could expect anything more than light chop. Supplemental information from acn 403022: the seatbelt sign was on and all passenger were seated and strapped. The flight attendants were not seated at the time. We were en route to lax from pit and diverted to okc.

Original NASA ASRS Text

Title: CABIN ATTENDANTS ON B757-200 INJURED WHEN ACFT ENCOUNTERED SEVERE JOLT OF TURB.

Narrative: IN AND OUT OF CLOUDS, THE CAPT ILLUMINATED THE SEAT BELT SIGN AND MADE APPROPRIATE PA. THE ONLY RETURNS ON RADAR WERE APPROX 60 MI N. LIGHT CHOP DEVELOPED, WHICH RAPIDLY ESCALATED TO MODERATE TO SEVERE AND CULMINATED IN ONE ESPECIALLY SEVERE JOLT. JUST BEFORE THE SEVERE JOLT, IN AND OUT OF CIRRUS, I SAW A BUILD-UP SLIGHTLY OFF TO THE R. THIS WAS NOT SHOWING ON RADAR. WE RPTED SEVERE TURB TO ATC AND DIVERTED TO OKC AFTER CABIN CREW RPTED INJURIES. DSCNT, APCH, AND LNDG WERE NORMAL WITH ACFT HANDLING NORMAL. 4 FLT ATTENDANTS INJURED. THERE WAS JUST LIGHT CHOP BEING RPTED IN THE GENERAL AREA. THERE WERE NO RETURNS WITHIN 60 DEGS OF THE NOSE. EVERY TOOL AND CUES DIDN'T GIVE US ANY INDICATION THAT WE COULD EXPECT ANYTHING MORE THAN LIGHT CHOP. SUPPLEMENTAL INFO FROM ACN 403022: THE SEATBELT SIGN WAS ON AND ALL PAX WERE SEATED AND STRAPPED. THE FLT ATTENDANTS WERE NOT SEATED AT THE TIME. WE WERE ENRTE TO LAX FROM PIT AND DIVERTED TO OKC.

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.