TCASII. ATC flight crew miscom on assigned altitude.

Attributes
ACN	320920
Time
Date	199511
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ott
State Reference	MD
Altitude	msl bound lower : 25000 msl bound upper : 27000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc
Operator	common carrier : air carrier
Make Model Name	B727-200
Operating Under FAR Part	Part 121
Flight Phase	cruise other descent other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	320920
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
ASRS Report	320919
Events
Anomaly	altitude deviation : overshoot conflict : airborne less severe non adherence : clearance other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 0 vertical : 2000
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Pilot Deviation other

Narrative:

While at FL370 all crew members heard ATC clear us to descend to FL240 and to be there in 4 mins. While passing FL270 ATC called and questioned our altitude. We told them we were out of FL270 for FL240. We were then cleared to level at FL250. About that time we received a TCASII alert over gve on frequency 133.72 ZDC.

Original NASA ASRS Text

Title: TCASII. ATC FLC MISCOM ON ASSIGNED ALT.

Narrative: WHILE AT FL370 ALL CREW MEMBERS HEARD ATC CLR US TO DSND TO FL240 AND TO BE THERE IN 4 MINS. WHILE PASSING FL270 ATC CALLED AND QUESTIONED OUR ALT. WE TOLD THEM WE WERE OUT OF FL270 FOR FL240. WE WERE THEN CLRED TO LEVEL AT FL250. ABOUT THAT TIME WE RECEIVED A TCASII ALERT OVER GVE ON FREQ 133.72 ZDC.

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.