B757-200 crew was required to declare an emergency in order to be avoid being rted into a thundersto...

Attributes
ACN	622888
Time
Date	200407
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	intersection : wever
State Reference	FL
Altitude	msl single value : 25000
Environment
Weather Elements	Thunderstorm
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zma.artcc
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	descent : vacating altitude descent : intermediate altitude
Route In Use	arrival star : duval
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain
ASRS Report	622888
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	623013
Events
Anomaly	inflight encounter : weather other spatial deviation
Independent Detector	aircraft equipment other aircraft equipment : wx radar other flight crewa other flight crewb
Resolutory Action	flight crew : declared emergency flight crew : took precautionary avoidance action
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Weather FAA
Primary Problem	Weather

Narrative:

During duval arrival, we were cleared direct from maxim intersection to wever to cross at 14000 ft and 250 KTS. We had just been handed off to a new sector shortly after passing over key west. WX radar and visual examination indicated 2 significant cells between our position and wever. I was unable to determine the hts of the cells, but they were clearly over FL300 with continuing vertical development. The only safe route around the WX was a right deviation of about 15 degrees. The first officer requested the deviation. Controller said we could only go left with a heading of 360 degrees. I told the controller that was not acceptable because it would take us directly through the larger of the 2 cells. He said that mia approach would not let him approve east deviations and the only way we could go that way would be to declare an emergency and squawk 7700. I responded that was our only option and that we would squawk 7700 and begin the deviation. We were directed that after the deviation to return to previously assigned squawk. I would estimate that the deviation was less than 10 mi east of course. Our TCASII scan of 40 mi did not indicate any other aircraft in our vicinity.

Original NASA ASRS Text

Title: B757-200 CREW WAS REQUIRED TO DECLARE AN EMER IN ORDER TO BE AVOID BEING RTED INTO A TSTM.

Narrative: DURING DUVAL ARR, WE WERE CLRED DIRECT FROM MAXIM INTXN TO WEVER TO CROSS AT 14000 FT AND 250 KTS. WE HAD JUST BEEN HANDED OFF TO A NEW SECTOR SHORTLY AFTER PASSING OVER KEY WEST. WX RADAR AND VISUAL EXAM INDICATED 2 SIGNIFICANT CELLS BTWN OUR POS AND WEVER. I WAS UNABLE TO DETERMINE THE HTS OF THE CELLS, BUT THEY WERE CLRLY OVER FL300 WITH CONTINUING VERT DEVELOPMENT. THE ONLY SAFE RTE AROUND THE WX WAS A R DEV OF ABOUT 15 DEGS. THE FO REQUESTED THE DEV. CTLR SAID WE COULD ONLY GO L WITH A HDG OF 360 DEGS. I TOLD THE CTLR THAT WAS NOT ACCEPTABLE BECAUSE IT WOULD TAKE US DIRECTLY THROUGH THE LARGER OF THE 2 CELLS. HE SAID THAT MIA APCH WOULD NOT LET HIM APPROVE E DEVS AND THE ONLY WAY WE COULD GO THAT WAY WOULD BE TO DECLARE AN EMER AND SQUAWK 7700. I RESPONDED THAT WAS OUR ONLY OPTION AND THAT WE WOULD SQUAWK 7700 AND BEGIN THE DEV. WE WERE DIRECTED THAT AFTER THE DEV TO RETURN TO PREVIOUSLY ASSIGNED SQUAWK. I WOULD ESTIMATE THAT THE DEV WAS LESS THAN 10 MI E OF COURSE. OUR TCASII SCAN OF 40 MI DID NOT INDICATE ANY OTHER ACFT IN OUR VICINITY.

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.

B757-200 crew was required to declare an emergency in order to be avoid being rted into a thunderstorm.