A flight crew encountered severe WX and used PIC authority/authorized to exit the adverse environmen...

Attributes
ACN	592545
Time
Date	200308
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : ink.vortac
State Reference	TX
Altitude	msl bound lower : 31000 msl bound upper : 35000
Environment
Flight Conditions	IMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zab.artcc
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 10000 flight time type : 5000
ASRS Report	592545
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : weather inflight encounter : turbulence non adherence : clearance
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : took precautionary avoidance action flight crew : exited adverse environment
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Environmental Factor ATC Human Performance Weather Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

We were at FL350 and deviating through a line of thunderstorms. Radar showed a gap and no severe WX. Shortly after entering IMC, we encountered turbulence, electrical discharges (st elmo's fire), and airspeed began to decay. Copilot noticed a large temperature change. I used captain's authority/authorized and told copilot to descend to FL310 as I called ATC and requested an immediate descent to FL310, granted. Everything stabilized and flight continued. This all happened very quickly and was over. I have only seen one other 'unique' WX occurrence such as this in 30 yrs of flying. Fatigue may have contributed. Extensive ATC delays (1 hour 20 min taxi time), summer heat, and a 4 hour 50 min flight. I think the temperature change contributed to immediate and heavy icing. Sooner application of engine anti-ice would've helped, but it wasn't required to start with. Once situation occurred, crew handled it quickly and well.

Original NASA ASRS Text

Title: A FLT CREW ENCOUNTERED SEVERE WX AND USED PIC AUTH TO EXIT THE ADVERSE ENVIRONMENT.

Narrative: WE WERE AT FL350 AND DEVIATING THROUGH A LINE OF TSTMS. RADAR SHOWED A GAP AND NO SEVERE WX. SHORTLY AFTER ENTERING IMC, WE ENCOUNTERED TURB, ELECTRICAL DISCHARGES (ST ELMO'S FIRE), AND AIRSPD BEGAN TO DECAY. COPLT NOTICED A LARGE TEMP CHANGE. I USED CAPT'S AUTH AND TOLD COPLT TO DSND TO FL310 AS I CALLED ATC AND REQUESTED AN IMMEDIATE DSCNT TO FL310, GRANTED. EVERYTHING STABILIZED AND FLT CONTINUED. THIS ALL HAPPENED VERY QUICKLY AND WAS OVER. I HAVE ONLY SEEN ONE OTHER 'UNIQUE' WX OCCURRENCE SUCH AS THIS IN 30 YRS OF FLYING. FATIGUE MAY HAVE CONTRIBUTED. EXTENSIVE ATC DELAYS (1 HR 20 MIN TAXI TIME), SUMMER HEAT, AND A 4 HR 50 MIN FLT. I THINK THE TEMP CHANGE CONTRIBUTED TO IMMEDIATE AND HVY ICING. SOONER APPLICATION OF ENG ANTI-ICE WOULD'VE HELPED, BUT IT WASN'T REQUIRED TO START WITH. ONCE SIT OCCURRED, CREW HANDLED IT QUICKLY AND WELL.

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.

A flight crew encountered severe WX and used PIC authority/authorized to exit the adverse environment.