Altitude excursion for air carrier large transport.

Attributes
ACN	174343
Time
Date	199103
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : drk
State Reference	AZ
Altitude	msl bound lower : 33000 msl bound upper : 35000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zab
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	cruise other descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 10000 flight time type : 500
ASRS Report	174343
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was first officer on air carrier large transport at FL350. Approaching drake VOR, controller on previous frequency had said to expect to cross drake at FL310. On new frequency (132.9) over drake, I thought I heard our flight # called, and a clearance to FL31O. I read back the clearance and included our flight # in the readback. Approaching FL330, controller asked what altitude we were at, and I told him and reiterated that we were cleared to FL310, and that I read it back. He cleared us back to FL350 and gave us an off-course vector. Though TCASII showed numerous aircraft around, closest came about 7 mi horizontal at -200'. We received no TA from the TCAS. Eventually cleared back on course with nothing else said. Contributing factors: conversation going on in cockpit with jump seat rider and no one cabin attendant. Both pilots on the overhead speaker. Previous controller priming me for a descent. Controller working 2 frequencys at the same time. Was my readback blocked out by someone else reading back on another frequency? Many flight #south on frequency that sound the same. Corrective actions: wear earphone anytime a conversation is going on in cockpit. Try to pay closer attention to ATC when I have problems hearing my particular flight # called.

Original NASA ASRS Text

Title: ALT EXCURSION FOR ACR LGT.

Narrative: I WAS F/O ON ACR LGT AT FL350. APCHING DRAKE VOR, CTLR ON PREVIOUS FREQ HAD SAID TO EXPECT TO CROSS DRAKE AT FL310. ON NEW FREQ (132.9) OVER DRAKE, I THOUGHT I HEARD OUR FLT # CALLED, AND A CLRNC TO FL31O. I READ BACK THE CLRNC AND INCLUDED OUR FLT # IN THE READBACK. APCHING FL330, CTLR ASKED WHAT ALT WE WERE AT, AND I TOLD HIM AND REITERATED THAT WE WERE CLRED TO FL310, AND THAT I READ IT BACK. HE CLRED US BACK TO FL350 AND GAVE US AN OFF-COURSE VECTOR. THOUGH TCASII SHOWED NUMEROUS ACFT AROUND, CLOSEST CAME ABOUT 7 MI HORIZ AT -200'. WE RECEIVED NO TA FROM THE TCAS. EVENTUALLY CLRED BACK ON COURSE WITH NOTHING ELSE SAID. CONTRIBUTING FACTORS: CONVERSATION GOING ON IN COCKPIT WITH JUMP SEAT RIDER AND NO ONE CABIN ATTENDANT. BOTH PLTS ON THE OVERHEAD SPEAKER. PREVIOUS CTLR PRIMING ME FOR A DSNT. CTLR WORKING 2 FREQS AT THE SAME TIME. WAS MY READBACK BLOCKED OUT BY SOMEONE ELSE READING BACK ON ANOTHER FREQ? MANY FLT #S ON FREQ THAT SOUND THE SAME. CORRECTIVE ACTIONS: WEAR EARPHONE ANYTIME A CONVERSATION IS GOING ON IN COCKPIT. TRY TO PAY CLOSER ATTN TO ATC WHEN I HAVE PROBS HEARING MY PARTICULAR FLT # CALLED.

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.