Controller report of air carrier altitude deviation.

Attributes
ACN	295410
Time
Date	199502
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : rdu
State Reference	NC
Altitude	msl bound lower : 9500 msl bound upper : 10600
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : mem
Operator	common carrier : air carrier
Make Model Name	MD-80 Super 80
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	cruise other
Route In Use	enroute : on vectors enroute airway : rdu
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
ASRS Report	295410
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 other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Air carrier was inbound over aldan arrival gate at 10000 ft with a VFR eastbound at 9500 ft talking to ZDC. Traffic was issued. Air carrier climbed to 10600 ft and stated he thought the VFR aircraft was at 10000 ft with wrong mode C. Callback conversation with reporter revealed the following information: reporter states the air carrier indicated he had an RA which showed the VFR traffic was climbing. Reporter radar did not indicate this. VFR traffic was not in communication with controller but he was squawking mode C and indicating level at 9500. Air carrier returned to assigned altitude after discussion with reporter.

Original NASA ASRS Text

Title: CTLR RPT OF ACR ALTDEV.

Narrative: ACR WAS INBOUND OVER ALDAN ARR GATE AT 10000 FT WITH A VFR EBOUND AT 9500 FT TALKING TO ZDC. TFC WAS ISSUED. ACR CLBED TO 10600 FT AND STATED HE THOUGHT THE VFR ACFT WAS AT 10000 FT WITH WRONG MODE C. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THE ACR INDICATED HE HAD AN RA WHICH SHOWED THE VFR TFC WAS CLBING. RPTR RADAR DID NOT INDICATE THIS. VFR TFC WAS NOT IN COM WITH CTLR BUT HE WAS SQUAWKING MODE C AND INDICATING LEVEL AT 9500. ACR RETURNED TO ASSIGNED ALT AFTER DISCUSSION WITH RPTR.

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.