CL65 crew was climbing to FL270. The ARTCC radar controller thought they were climbing to FL250.

Attributes
ACN	638972
Time
Date	200412
Day	Thu
Local Time Of Day	0001 To 0600
Place
Locale Reference	navaid : irq.vortac
State Reference	SC
Altitude	msl bound lower : 25000 msl bound upper : 27000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : ztl.artcc
Operator	common carrier : air carrier
Make Model Name	Regional Jet CL65, Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi
Experience	flight time last 90 days : 250 flight time total : 6700 flight time type : 4000
ASRS Report	638972
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : overshoot non adherence : clearance
Independent Detector	other controllera
Resolutory Action	controller : issued alert flight crew : returned to assigned altitude
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	Ambiguous

Narrative:

We were climbing to what we perceived to be our final altitude of FL270. Out of FL258, center asked us to check altitude, advising we were only cleared to FL250. We immediately initiated a quick descent to FL250. There was no other traffic around us. A quick check of our flight plan revealed indeed a FL250 filing. The altitude alerter was set to FL270. We are still in a quandary about what happened, whether we took another radio call or the wrong altitude was set incorrectly in the alerter (when we thought it was correct, we don't know. One thing we are sure about is that it was clearly wrong. We did check on initially with center stating we were climbing to FL270, but something clearly was missed. More attention and diligence is required to avoid a future incident.

Original NASA ASRS Text

Title: CL65 CREW WAS CLBING TO FL270. THE ARTCC RADAR CTLR THOUGHT THEY WERE CLBING TO FL250.

Narrative: WE WERE CLBING TO WHAT WE PERCEIVED TO BE OUR FINAL ALT OF FL270. OUT OF FL258, CTR ASKED US TO CHK ALT, ADVISING WE WERE ONLY CLRED TO FL250. WE IMMEDIATELY INITIATED A QUICK DSCNT TO FL250. THERE WAS NO OTHER TFC AROUND US. A QUICK CHK OF OUR FLT PLAN REVEALED INDEED A FL250 FILING. THE ALT ALERTER WAS SET TO FL270. WE ARE STILL IN A QUANDARY ABOUT WHAT HAPPENED, WHETHER WE TOOK ANOTHER RADIO CALL OR THE WRONG ALT WAS SET INCORRECTLY IN THE ALERTER (WHEN WE THOUGHT IT WAS CORRECT, WE DON'T KNOW. ONE THING WE ARE SURE ABOUT IS THAT IT WAS CLRLY WRONG. WE DID CHK ON INITIALLY WITH CTR STATING WE WERE CLBING TO FL270, BUT SOMETHING CLRLY WAS MISSED. MORE ATTN AND DILIGENCE IS REQUIRED TO AVOID A FUTURE INCIDENT.

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.