Air carrier large transport turbulence encounter on descent into bwi.

Attributes
ACN	182899
Time
Date	199107
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : bwi
State Reference	MA
Altitude	msl bound lower : 15000 msl bound upper : 15200
Environment
Flight Conditions	Mixed
Light	Night
Aircraft 1
Controlling Facilities	tracon : iad
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial
Experience	flight time last 90 days : 120 flight time total : 5000
ASRS Report	182899
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : weather
Independent Detector	other flight crewa
Resolutory Action	flight crew : exited adverse environment
Consequence	other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other

Narrative:

Flight from detroit to bwi after descending from FL290 to 15000'. Aircraft was level at 15000' with autoplt on. Deviating around large cell at 10 O'clock. Low cumulus below us with 12000-15000' tops. Airspeed 280-290 KTS. Heading approximately 120 degrees. We were flying south of track to avoid large cell and missing small buildups. With landing lights on we saw clouds ahead got a short period of rain and light turbulence and 1 large jolt. Turned further south and broke into clear. Seatbelt sign was on. F/a was going through cabin and checking passenger. 4 people were taken to bwi area hospitals to be checked and released. During the large, severe jolt, I took off autoplt and turned south and corrected to altitude of 15000'. I saw 15200', but may have been higher during severe jolt. Our radar showed nothing along our route of flight. After our turbulence the controller asked how our ride was as she had some indication of the bad WX on our altitude deviation. Medical personnel met the aircraft at the gate. Maintenance pulled the flight recorder and did a complete inspection. The other 2 pilots filled out NASA forms, also.

Original NASA ASRS Text

Title: ACR LGT TURBULENCE ENCOUNTER ON DESCENT INTO BWI.

Narrative: FLT FROM DETROIT TO BWI AFTER DSNDING FROM FL290 TO 15000'. ACFT WAS LEVEL AT 15000' WITH AUTOPLT ON. DEVIATING AROUND LARGE CELL AT 10 O'CLOCK. LOW CUMULUS BELOW US WITH 12000-15000' TOPS. AIRSPD 280-290 KTS. HDG APPROX 120 DEGS. WE WERE FLYING S OF TRACK TO AVOID LARGE CELL AND MISSING SMALL BUILDUPS. WITH LNDG LIGHTS ON WE SAW CLOUDS AHEAD GOT A SHORT PERIOD OF RAIN AND LIGHT TURB AND 1 LARGE JOLT. TURNED FURTHER S AND BROKE INTO CLR. SEATBELT SIGN WAS ON. F/A WAS GOING THROUGH CABIN AND CHKING PAX. 4 PEOPLE WERE TAKEN TO BWI AREA HOSPITALS TO BE CHKED AND RELEASED. DURING THE LARGE, SEVERE JOLT, I TOOK OFF AUTOPLT AND TURNED S AND CORRECTED TO ALT OF 15000'. I SAW 15200', BUT MAY HAVE BEEN HIGHER DURING SEVERE JOLT. OUR RADAR SHOWED NOTHING ALONG OUR RTE OF FLT. AFTER OUR TURB THE CTLR ASKED HOW OUR RIDE WAS AS SHE HAD SOME INDICATION OF THE BAD WX ON OUR ALT DEVIATION. MEDICAL PERSONNEL MET THE ACFT AT THE GATE. MAINT PULLED THE FLT RECORDER AND DID A COMPLETE INSPECTION. THE OTHER 2 PLTS FILLED OUT NASA FORMS, ALSO.

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.