FK10 crew and controller disputed altitude clearance.

Attributes
ACN	457170
Time
Date	199912
Day	Mon
Local Time Of Day	1201 To 1800
Place
State Reference	KY
Altitude	msl bound lower : 2000 msl bound upper : 11000
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sdf.tracon
Operator	common carrier : air carrier
Make Model Name	Fokker 100
Operating Under FAR Part	Part 121
Flight Phase	descent : vacating altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	457170
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : commercial pilot : instrument
ASRS Report	457169
Events
Anomaly	altitude deviation : overshoot non adherence : published procedure non adherence : far
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance controller : issued alert
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	ATC Human Performance

Narrative:

Altitude deviation. Cleared to and read back a clearance from 11000 ft to 2000 ft. Passing 4200 ft, approach asked if we were going to level at 5000 ft. I replied we were descending to 2000 ft as we had read back. They initially told us to climb back to 5000 ft, then told us to stay at 4000 ft. No traffic conflict resulted - the rest was uneventful. Supplemental information from acn 457169: while descending into sdf, we were cleared to 2000 ft and read back 2000 ft. Captain and first officer (PF) both heard 2000 ft. Passing 3500 ft, we were asked to confirm our altitude. We were then told to climb back up to 5000 ft. Soon after, he revised the altitude to 4000 ft. Good WX, little traffic, uneventful landing. I swear I heard 2000 ft.

Original NASA ASRS Text

Title: FK10 CREW AND CTLR DISPUTED ALT CLRNC.

Narrative: ALTDEV. CLRED TO AND READ BACK A CLRNC FROM 11000 FT TO 2000 FT. PASSING 4200 FT, APCH ASKED IF WE WERE GOING TO LEVEL AT 5000 FT. I REPLIED WE WERE DSNDING TO 2000 FT AS WE HAD READ BACK. THEY INITIALLY TOLD US TO CLB BACK TO 5000 FT, THEN TOLD US TO STAY AT 4000 FT. NO TFC CONFLICT RESULTED - THE REST WAS UNEVENTFUL. SUPPLEMENTAL INFO FROM ACN 457169: WHILE DSNDING INTO SDF, WE WERE CLRED TO 2000 FT AND READ BACK 2000 FT. CAPT AND FO (PF) BOTH HEARD 2000 FT. PASSING 3500 FT, WE WERE ASKED TO CONFIRM OUR ALT. WE WERE THEN TOLD TO CLB BACK UP TO 5000 FT. SOON AFTER, HE REVISED THE ALT TO 4000 FT. GOOD WX, LITTLE TFC, UNEVENTFUL LNDG. I SWEAR I HEARD 2000 FT.

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.