Fgt climbed through the altitude occupied by another aircraft without clearance.

Attributes
ACN	120378
Time
Date	198908
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ccv
State Reference	VA
Altitude	msl bound lower : 10000 msl bound upper : 12000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : orf tower : ttn
Operator	other
Make Model Name	Fighter
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Transport, Low Wing, 2 Turboprop Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller military : 4 controller radar : 5
ASRS Report	120378
Person 2
Affiliation	government : military
Function	flight crew : single pilot
Qualification	pilot : military
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Miss Distance	horizontal : 9000 vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was working 2 sectors combined. A stationary front with a line of thunderstorms was holding through the sector. The sectors were busy. All aircraft had to be vectored around WX. Everybody was deviating. Lots of coordination with center. I stopped departure into the sector and asked a supervisor to split the positions, and was told we did not have the bodies. I took a navy fgt at 10,000 from center (not ARTS tracked). The aircraft was wbound deviating. An mdt was northeast bound at 11,000. One of the first mode C hits on the fgt showed 12,000. I questioned his altitude, he reported level at 12,000. At this point the mdt was 12 O'clock and 1 1/2 mi. I do not know at what point the fgt climbed to 12,000. I'm certain he checked in at 10,000. Once the fgt passed the mdt, I descended him to 10,000. The fgt might have acknowledged another aircraft's transmission (however, nobody was climbed to 12,000). If this happened I did not catch it. I was working 4 frequencys. When the other aircraft checked in at 12,000, they were advised to maintain 12,000. The problem was caused by not splitting a busy sector due to staffing shortages.

Original NASA ASRS Text

Title: FGT CLIMBED THROUGH THE ALT OCCUPIED BY ANOTHER ACFT WITHOUT CLRNC.

Narrative: I WAS WORKING 2 SECTORS COMBINED. A STATIONARY FRONT WITH A LINE OF TSTMS WAS HOLDING THROUGH THE SECTOR. THE SECTORS WERE BUSY. ALL ACFT HAD TO BE VECTORED AROUND WX. EVERYBODY WAS DEVIATING. LOTS OF COORD WITH CENTER. I STOPPED DEP INTO THE SECTOR AND ASKED A SUPVR TO SPLIT THE POSITIONS, AND WAS TOLD WE DID NOT HAVE THE BODIES. I TOOK A NAVY FGT AT 10,000 FROM CENTER (NOT ARTS TRACKED). THE ACFT WAS WBOUND DEVIATING. AN MDT WAS NE BOUND AT 11,000. ONE OF THE FIRST MODE C HITS ON THE FGT SHOWED 12,000. I QUESTIONED HIS ALT, HE REPORTED LEVEL AT 12,000. AT THIS POINT THE MDT WAS 12 O'CLOCK AND 1 1/2 MI. I DO NOT KNOW AT WHAT POINT THE FGT CLIMBED TO 12,000. I'M CERTAIN HE CHECKED IN AT 10,000. ONCE THE FGT PASSED THE MDT, I DESCENDED HIM TO 10,000. THE FGT MIGHT HAVE ACKNOWLEDGED ANOTHER ACFT'S XMISSION (HOWEVER, NOBODY WAS CLIMBED TO 12,000). IF THIS HAPPENED I DID NOT CATCH IT. I WAS WORKING 4 FREQS. WHEN THE OTHER ACFT CHECKED IN AT 12,000, THEY WERE ADVISED TO MAINTAIN 12,000. THE PROBLEM WAS CAUSED BY NOT SPLITTING A BUSY SECTOR DUE TO STAFFING SHORTAGES.

Data retrieved from NASA's ASRS site as of August 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.