BE20 crew flew into a thunderstorm cell in ZLC class a airspace.

Attributes
ACN	485743
Time
Date	200009
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : ocs.vortac
State Reference	WY
Altitude	msl bound lower : 27000 msl bound upper : 27800
Environment
Flight Conditions	IMC
Weather Elements	Ice Turbulence other
Aircraft 1
Controlling Facilities	artcc : zlc.artcc
Operator	general aviation : corporate
Make Model Name	Super King Air 200/Huron
Operating Under FAR Part	Part 91
Navigation In Use	other vortac
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 6300 flight time type : 350
ASRS Report	485743
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : weather inflight encounter : turbulence inflight encounter other non adherence : company policies non adherence : published procedure other anomaly other
Independent Detector	other flight crewa other flight crewb other other : 3
Resolutory Action	flight crew : regained aircraft control
Consequence	other other Other
Supplementary
Problem Areas	Flight Crew Human Performance Weather
Primary Problem	Flight Crew Human Performance

Narrative:

After smoothly crossing an area of cells, we returned to course and secured the area ahead on various radar ranges, since we were still in clouds. Nothing painted. About 10 mins after passing the last cell, we hit a small diameter, violent, ice-laden cell. It did not show on radar. Before I could grasp power levers and reduce power we were thrown down violently and then up violently. We were about 800 ft high and in light turbulence within 15 seconds. We advised ATC and returned to altitude. The copilot immediately went aft to assist passenger, who were all restrained by seat belts. Their dog, however, was killed by violent roof/floor impact. The tiny dog was fine, but the bigger dog (35 pounds) broke its spine. Copilot also inspected wings for large-scale damage. I did the same from cockpit. No apparent wrinkles. We opted to finish flight at minimum maneuvering speed and do detailed inspection on ground. Ground inspection revealed subtle wrinkles in several places on both wings and both nacelles. Many rivets also lost paint. Plane grounded for further inspection/repair. Lessons: 1) not all severe cumiliform WX can be detected by radar. 2) you are not out of the WX until you are visually out of the WX. 3) if you suspect damage, land as soon as possible. You cannot see detail from cabin/cockpit windows. 4) animals should be restrained or kenneled, unless owner is willing to lose them.

Original NASA ASRS Text

Title: BE20 CREW FLEW INTO A TSTM CELL IN ZLC CLASS A AIRSPACE.

Narrative: AFTER SMOOTHLY XING AN AREA OF CELLS, WE RETURNED TO COURSE AND SECURED THE AREA AHEAD ON VARIOUS RADAR RANGES, SINCE WE WERE STILL IN CLOUDS. NOTHING PAINTED. ABOUT 10 MINS AFTER PASSING THE LAST CELL, WE HIT A SMALL DIAMETER, VIOLENT, ICE-LADEN CELL. IT DID NOT SHOW ON RADAR. BEFORE I COULD GRASP PWR LEVERS AND REDUCE PWR WE WERE THROWN DOWN VIOLENTLY AND THEN UP VIOLENTLY. WE WERE ABOUT 800 FT HIGH AND IN LIGHT TURB WITHIN 15 SECONDS. WE ADVISED ATC AND RETURNED TO ALT. THE COPLT IMMEDIATELY WENT AFT TO ASSIST PAX, WHO WERE ALL RESTRAINED BY SEAT BELTS. THEIR DOG, HOWEVER, WAS KILLED BY VIOLENT ROOF/FLOOR IMPACT. THE TINY DOG WAS FINE, BUT THE BIGGER DOG (35 LBS) BROKE ITS SPINE. COPLT ALSO INSPECTED WINGS FOR LARGE-SCALE DAMAGE. I DID THE SAME FROM COCKPIT. NO APPARENT WRINKLES. WE OPTED TO FINISH FLT AT MINIMUM MANEUVERING SPD AND DO DETAILED INSPECTION ON GND. GND INSPECTION REVEALED SUBTLE WRINKLES IN SEVERAL PLACES ON BOTH WINGS AND BOTH NACELLES. MANY RIVETS ALSO LOST PAINT. PLANE GNDED FOR FURTHER INSPECTION/REPAIR. LESSONS: 1) NOT ALL SEVERE CUMILIFORM WX CAN BE DETECTED BY RADAR. 2) YOU ARE NOT OUT OF THE WX UNTIL YOU ARE VISUALLY OUT OF THE WX. 3) IF YOU SUSPECT DAMAGE, LAND ASAP. YOU CANNOT SEE DETAIL FROM CABIN/COCKPIT WINDOWS. 4) ANIMALS SHOULD BE RESTRAINED OR KENNELED, UNLESS OWNER IS WILLING TO LOSE THEM.

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.