Citation 525B flight crew has an altitude deviation and a subsequent TCAS TA.

Attributes
ACN	701638
Time
Date	200606
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : ict.vortac
State Reference	KS
Altitude	msl single value : 23000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zkc.artcc
Operator	general aviation : corporate
Make Model Name	Cessna Citation Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zkc.artcc
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise : level
Person 1
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : cfi pilot : multi engine pilot : atp
Experience	flight time last 90 days : 150 flight time total : 4500 flight time type : 600
ASRS Report	701638
Person 2
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance
Independent Detector	aircraft equipment : tcas other controllera
Resolutory Action	controller : issued advisory controller : issued new clearance flight crew : returned to assigned altitude
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Level at FL230 and heading 270 degrees; ATC instructed left turn heading 260 degrees. Flight plan altitude was FL450; so we were expecting clearance to a higher altitude. The PF selected a climb to FL260 with the altitude preselector. I called ATC back to verify the request; the immediate response was to turn left 40 degrees and maintain FL230. ATC also called the aircraft at our 12 O'clock position and 1000 ft above and requested an immediate left turn. The TCAS TA called 'traffic; traffic' and indicated an amber TA. I disconnected the autoplt. Pitched down and turned left. The aircraft had climbed 300 ft toward the other aircraft; with a TCAS vertical separation of 700 ft. We leveled at FL230 and resumed heading 260 degrees as the traffic passed overhead.

Original NASA ASRS Text

Title: CITATION 525B FLT CREW HAS AN ALTDEV AND A SUBSEQUENT TCAS TA.

Narrative: LEVEL AT FL230 AND HDG 270 DEGS; ATC INSTRUCTED L TURN HDG 260 DEGS. FLT PLAN ALT WAS FL450; SO WE WERE EXPECTING CLRNC TO A HIGHER ALT. THE PF SELECTED A CLB TO FL260 WITH THE ALT PRESELECTOR. I CALLED ATC BACK TO VERIFY THE REQUEST; THE IMMEDIATE RESPONSE WAS TO TURN L 40 DEGS AND MAINTAIN FL230. ATC ALSO CALLED THE ACFT AT OUR 12 O'CLOCK POS AND 1000 FT ABOVE AND REQUESTED AN IMMEDIATE L TURN. THE TCAS TA CALLED 'TFC; TFC' AND INDICATED AN AMBER TA. I DISCONNECTED THE AUTOPLT. PITCHED DOWN AND TURNED L. THE ACFT HAD CLBED 300 FT TOWARD THE OTHER ACFT; WITH A TCAS VERT SEPARATION OF 700 FT. WE LEVELED AT FL230 AND RESUMED HDG 260 DEGS AS THE TFC PASSED OVERHEAD.

Data retrieved from NASA's ASRS site as of January 2009 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.