C560 landing ptk descends through ATC assigned altitude.

Attributes
ACN	579915
Time
Date	200304
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	intersection : sprtn
State Reference	MI
Altitude	msl bound lower : 7000 msl bound upper : 9000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : corporate
Make Model Name	Citation Excel
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 90 flight time total : 12000 flight time type : 900
ASRS Report	579915
Person 2
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Events
Anomaly	altitude deviation : overshoot non adherence : published procedure
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	ATC Human Performance

Narrative:

I was the PF, PNF on radio. We were IFR en route from mdw to ptk in VMC. In the descent from flight levels, descending through approximately 17000 ft MSL, lansing approach cleared us to 'descend to cross spartan at and maintain 5000 ft.' we (captain, PNF) read back the 5000 ft clearance. I was listening and it was clear to both of us that it was 5000 ft.' descending through about 7000 ft, lansing approach called and asked about our altitude, and informed us that she had cleared us to descend to cross spartan at 9000 ft. PNF informed controller 'we heard and read back 'fife' [reporter's spelling] thousand. We never heard 'niner' thousand as 'nine' should be spoken phonetically. The controller coordinated the altitude error with dtw approach as she was about to complete the handoff anyway. She stated there were 'no conflicts, no problem.' we were in good VMC with TCASII and observed no conflicts. This could have been avoided by the controller using proper phonetic pronunciations of numbers, ie, 'five=fife' and 'nine=niner.' this goes back to the basics!

Original NASA ASRS Text

Title: C560 LNDG PTK DSNDS THROUGH ATC ASSIGNED ALT.

Narrative: I WAS THE PF, PNF ON RADIO. WE WERE IFR ENRTE FROM MDW TO PTK IN VMC. IN THE DSCNT FROM FLT LEVELS, DSNDING THROUGH APPROX 17000 FT MSL, LANSING APCH CLRED US TO 'DSND TO CROSS SPARTAN AT AND MAINTAIN 5000 FT.' WE (CAPT, PNF) READ BACK THE 5000 FT CLRNC. I WAS LISTENING AND IT WAS CLR TO BOTH OF US THAT IT WAS 5000 FT.' DSNDING THROUGH ABOUT 7000 FT, LANSING APCH CALLED AND ASKED ABOUT OUR ALT, AND INFORMED US THAT SHE HAD CLRED US TO DSND TO CROSS SPARTAN AT 9000 FT. PNF INFORMED CTLR 'WE HEARD AND READ BACK 'FIFE' [RPTR'S SPELLING] THOUSAND. WE NEVER HEARD 'NINER' THOUSAND AS 'NINE' SHOULD BE SPOKEN PHONETICALLY. THE CTLR COORDINATED THE ALT ERROR WITH DTW APCH AS SHE WAS ABOUT TO COMPLETE THE HDOF ANYWAY. SHE STATED THERE WERE 'NO CONFLICTS, NO PROB.' WE WERE IN GOOD VMC WITH TCASII AND OBSERVED NO CONFLICTS. THIS COULD HAVE BEEN AVOIDED BY THE CTLR USING PROPER PHONETIC PRONUNCIATIONS OF NUMBERS, IE, 'FIVE=FIFE' AND 'NINE=NINER.' THIS GOES BACK TO THE BASICS!

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.