Air carrier large transport diverted to unlisted alternate due to thunderstorm activity.

Attributes
ACN	108301
Time
Date	198904
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : ilm
State Reference	NC
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : ilm
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	landing other other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 150 flight time total : 8500
ASRS Report	108301
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : atp pilot : flight engineer pilot : instrument
Experience	flight time last 90 days : 100 flight time total : 5000 flight time type : 2000
ASRS Report	108297
Events
Anomaly	inflight encounter : weather non adherence : far
Independent Detector	other flight crewa
Resolutory Action	flight crew : exited adverse environment none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	Pilot Deviation

Narrative:

Scheduled flight from mco to rdu. Held vicinity rdu due to trw activity. Diverted to first alternate due to fuel limitations. WX en route caused me to re-evaluate the suitability of the chosen alternate. Diverted to second alternate and discovered WX to block our route of flight (thunderstorms). Selected a third alternate but had to abandon that one as well due to active thunderstorm over field. Fourth alternate (ilm) was good in terms of WX, ATC and airport facs, but was not an airport authority/authorized for use by my company. With just about an hour's worth of fuel remaining on board, I had little choice but to make use of ilm as my alternate for landing. Landed safely and west/O incident. More timely reporting of actual en route WX would have enabled me to make a firm decision earlier in the flight and perhaps avoided landing at an off route airport. Supplemental information from acn 108297: we diverted to ilm because it was clear and the captain was familiar with the airport. Note: radar was marginal.

Original NASA ASRS Text

Title: ACR LGT DIVERTED TO UNLISTED ALTERNATE DUE TO TSTM ACTIVITY.

Narrative: SCHEDULED FLT FROM MCO TO RDU. HELD VICINITY RDU DUE TO TRW ACTIVITY. DIVERTED TO FIRST ALTERNATE DUE TO FUEL LIMITATIONS. WX ENRTE CAUSED ME TO RE-EVALUATE THE SUITABILITY OF THE CHOSEN ALTERNATE. DIVERTED TO SECOND ALTERNATE AND DISCOVERED WX TO BLOCK OUR ROUTE OF FLT (TSTMS). SELECTED A THIRD ALTERNATE BUT HAD TO ABANDON THAT ONE AS WELL DUE TO ACTIVE TSTM OVER FIELD. FOURTH ALTERNATE (ILM) WAS GOOD IN TERMS OF WX, ATC AND ARPT FACS, BUT WAS NOT AN ARPT AUTH FOR USE BY MY COMPANY. WITH JUST ABOUT AN HOUR'S WORTH OF FUEL REMAINING ON BOARD, I HAD LITTLE CHOICE BUT TO MAKE USE OF ILM AS MY ALTERNATE FOR LNDG. LANDED SAFELY AND W/O INCIDENT. MORE TIMELY RPTING OF ACTUAL ENRTE WX WOULD HAVE ENABLED ME TO MAKE A FIRM DECISION EARLIER IN THE FLT AND PERHAPS AVOIDED LNDG AT AN OFF ROUTE ARPT. SUPPLEMENTAL INFO FROM ACN 108297: WE DIVERTED TO ILM BECAUSE IT WAS CLR AND THE CAPT WAS FAMILIAR WITH THE ARPT. NOTE: RADAR WAS MARGINAL.

Data retrieved from NASA's ASRS site as of August 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.