An atx pilot overshoots his assigned altitude when he misunderstands the clearance to 9000 ft nnw of...

Attributes
ACN	464460
Time
Date	200002
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : dsd.vortac
State Reference	OR
Altitude	msl bound lower : 7200 msl bound upper : 9000
Environment
Flight Conditions	VMC
Light	Dawn
Aircraft 1
Controlling Facilities	artcc : zse.artcc
Operator	common carrier : air taxi
Make Model Name	PA-31 Navajo Chieftan/Mojave/Navajo T1020
Operating Under FAR Part	Part 135
Navigation In Use	other vortac
Flight Phase	cruise : enroute altitude change
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zse.artcc
Operator	common carrier : air carrier
Make Model Name	Dash 8 Series Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air taxi
Function	flight crew : single pilot
Qualification	pilot : atp pilot : cfi pilot : commercial pilot : instrument pilot : multi engine
Experience	flight time last 90 days : 60 flight time total : 2900 flight time type : 45
ASRS Report	464460
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : overshoot non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued advisory controller : separated traffic other
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was level at 11000 ft, sebound on V595 from pdx to rdm via dsd VOR. I thought the controller cleared me to 7000 ft, but later he told me he only cleared me to 9000 ft. I started my descent from 11000 ft to 7000 ft. When I was near 7700 ft to 8000 ft, he called me back to confirm I was leveling at 9000 ft. I told him 'I thought you said 7000 ft.' he told me 'no, 9000 ft.' so I immediately climbed back up to 9000 ft and told him 'leveling at 9000 ft.' there was an air carrier flight off of rdm and level at 8000 ft. He asked each of us to report the other in sight, and we both did. I think the main reason for the error was my fatigue brought on by my hectic flight schedule and also being a single pilot operation. There was no traffic conflict with the air carrier flight and we had each other in sight.

Original NASA ASRS Text

Title: AN ATX PLT OVERSHOOTS HIS ASSIGNED ALT WHEN HE MISUNDERSTANDS THE CLRNC TO 9000 FT NNW OF DSD, OR.

Narrative: I WAS LEVEL AT 11000 FT, SEBOUND ON V595 FROM PDX TO RDM VIA DSD VOR. I THOUGHT THE CTLR CLRED ME TO 7000 FT, BUT LATER HE TOLD ME HE ONLY CLRED ME TO 9000 FT. I STARTED MY DSCNT FROM 11000 FT TO 7000 FT. WHEN I WAS NEAR 7700 FT TO 8000 FT, HE CALLED ME BACK TO CONFIRM I WAS LEVELING AT 9000 FT. I TOLD HIM 'I THOUGHT YOU SAID 7000 FT.' HE TOLD ME 'NO, 9000 FT.' SO I IMMEDIATELY CLBED BACK UP TO 9000 FT AND TOLD HIM 'LEVELING AT 9000 FT.' THERE WAS AN ACR FLT OFF OF RDM AND LEVEL AT 8000 FT. HE ASKED EACH OF US TO RPT THE OTHER IN SIGHT, AND WE BOTH DID. I THINK THE MAIN REASON FOR THE ERROR WAS MY FATIGUE BROUGHT ON BY MY HECTIC FLT SCHEDULE AND ALSO BEING A SINGLE PLT OP. THERE WAS NO TFC CONFLICT WITH THE ACR FLT AND WE HAD EACH OTHER IN SIGHT.

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.

An atx pilot overshoots his assigned altitude when he misunderstands the clearance to 9000 ft nnw of dsd, or.