Air carrier allegedly descended below assigned altitude.

Attributes
ACN	187234
Time
Date	199108
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : fll
State Reference	FL
Altitude	msl bound lower : 24000 msl bound upper : 25000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zma
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	arrival other enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	187234
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
ASRS Report	187235
Events
Anomaly	altitude deviation : overshoot conflict : ground less severe non adherence : clearance
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	faa : investigated faa : reviewed incident with flight crew
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	other

Narrative:

The flight was deviating around thunderstorms in the south florida area for the fortl 1 arrival to ft lauderdale. The arrival was changed to direct collier county to intercept the dolin 2 arrival due to extensive thunderstorm activity. The arrival was then modified to direct collier county for vectors to ft lauderdale. The flight was being descended in incremental step downs from FL370. The crew recollection of the conflicting altitude was clearance to FL240. Miami center recollection is clearance to FL250. Center advised the flight to turn right and descend quickly from 240 to 230. Inquiries and discussion followed, and follow up action is in progress by both crew and center.

Original NASA ASRS Text

Title: ACR ALLEGEDLY DSNDED BELOW ASSIGNED ALT.

Narrative: THE FLT WAS DEVIATING AROUND TSTMS IN THE S FLORIDA AREA FOR THE FORTL 1 ARR TO FT LAUDERDALE. THE ARR WAS CHANGED TO DIRECT COLLIER COUNTY TO INTERCEPT THE DOLIN 2 ARR DUE TO EXTENSIVE TSTM ACTIVITY. THE ARR WAS THEN MODIFIED TO DIRECT COLLIER COUNTY FOR VECTORS TO FT LAUDERDALE. THE FLT WAS BEING DSNDED IN INCREMENTAL STEP DOWNS FROM FL370. THE CREW RECOLLECTION OF THE CONFLICTING ALT WAS CLRNC TO FL240. MIAMI CENTER RECOLLECTION IS CLRNC TO FL250. CENTER ADVISED THE FLT TO TURN R AND DSND QUICKLY FROM 240 TO 230. INQUIRIES AND DISCUSSION FOLLOWED, AND FOLLOW UP ACTION IS IN PROGRESS BY BOTH CREW AND CENTER.

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.