Assigned altitude amended but phraseology confusing. Altitude deviation.

Attributes
ACN	144566
Time
Date	199005
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : fsm
State Reference	AK
Altitude	msl bound lower : 8000 msl bound upper : 11000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zme
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 5200 flight time type : 200
ASRS Report	144566
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 2000 flight time type : 300
Events
Anomaly	altitude deviation : overshoot altitude deviation : crossing restriction not met non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Pilot Deviation other

Narrative:

We checked in with ZME with pilots discretion to 8000'. Then we were issued a clearance to cross 30 southwest of fsm at 11000'. While descending through 9700' we were asked to say altitude. We replied 9700' for 8000'. Then we asked center what our assigned altitude was. Center replied 11000'. Had center wanted to change our assigned altitude he should have stated either cross 30 southwest of fsm at 11000' and maintain 11000' , or amend altitude to maintain 11000' and cross 30 southwest of fsm at 11000'.

Original NASA ASRS Text

Title: ASSIGNED ALT AMENDED BUT PHRASEOLOGY CONFUSING. ALT DEVIATION.

Narrative: WE CHKED IN WITH ZME WITH PLTS DISCRETION TO 8000'. THEN WE WERE ISSUED A CLRNC TO CROSS 30 SW OF FSM AT 11000'. WHILE DSNDING THROUGH 9700' WE WERE ASKED TO SAY ALT. WE REPLIED 9700' FOR 8000'. THEN WE ASKED CTR WHAT OUR ASSIGNED ALT WAS. CTR REPLIED 11000'. HAD CTR WANTED TO CHANGE OUR ASSIGNED ALT HE SHOULD HAVE STATED EITHER CROSS 30 SW OF FSM AT 11000' AND MAINTAIN 11000' , OR AMEND ALT TO MAINTAIN 11000' AND CROSS 30 SW OF FSM AT 11000'.

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.