Deviation from assigned altitude.

Attributes
ACN	294820
Time
Date	199501
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : bce
State Reference	UT
Altitude	msl bound lower : 29000 msl bound upper : 29500
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zlc
Operator	common carrier : air carrier
Make Model Name	MD-80 Series (DC-9-80) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	294820
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Time XX42Z, FL290, approximately 60 DME southwest bce, ZLC asked for ride report at FL330. We thought we received clearance to climb to FL330 and read back climb clearance. At approximately FL295 center said we were not cleared to FL330. We returned to FL290. Both pilots believed we had been cleared to climb. Center frequency was difficult to understand the entire time. Upon subsequent clrncs to FL330 we asked the controller if any conflict had occurred. He replied none had occurred.

Original NASA ASRS Text

Title: DEV FROM ASSIGNED ALT.

Narrative: TIME XX42Z, FL290, APPROX 60 DME SW BCE, ZLC ASKED FOR RIDE RPT AT FL330. WE THOUGHT WE RECEIVED CLRNC TO CLB TO FL330 AND READ BACK CLB CLRNC. AT APPROX FL295 CTR SAID WE WERE NOT CLRED TO FL330. WE RETURNED TO FL290. BOTH PLTS BELIEVED WE HAD BEEN CLRED TO CLB. CTR FREQ WAS DIFFICULT TO UNDERSTAND THE ENTIRE TIME. UPON SUBSEQUENT CLRNCS TO FL330 WE ASKED THE CTLR IF ANY CONFLICT HAD OCCURRED. HE REPLIED NONE HAD OCCURRED.

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.