Operational error less than standard separation between military C12 climbing to FL220 and air carrier B757 climbing to FL210. Reporter in training and the OJT instructor thought the C12 was at FL220 when the B757 was cleared to FL210. Reporter said the military C12 mode C altitude readout was XXX for about a min and a half. No apparent altitude verification with the C12 before climbing the B757.

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Attributes
ACN	374952
Time
Date	199707
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ldn
State Reference	VA
Altitude	msl bound lower : 21000 msl bound upper : 21000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc
Operator	other
Make Model Name	Super King Air 200/Huron
Operating Under FAR Part	other : other
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude descent other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	other personnel other
Qualification	controller : developmental controller : radar
Experience	controller military : 3 controller radar : 9
ASRS Report	374952
Person 2
Affiliation	government : faa
Function	other personnel other
Qualification	controller : radar
Experience	controller radar : 4
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 21000 vertical : 500
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

I was radar training on departure sector, with 5 hours on position and trainer didn't have much experience as trainer. It was a busy departure push. A military C12 climbing to FL220 and behind same direction a B757 climbing to FL210. The C12 mode C had been XXX for at least a min and a half. I thought the C12 was level at FL220 and climbed the B757 to FL210. When the C12 mode C came back on it showed FL210 climbing to FL220. The B757 was already showing FL200 climbing to FL210, within 5 mi of the C12. At that time the C12 was told to expedite to FL220 and the B757 to maintain FL200, but separation was already lost. I think the C12's transponder was not working properly. It had not shown an altitude for a while, and I think if it was working the B757's TCASII would have given a TA or RA so as to not climb into the C12. I had not lost the picture completely, but I was getting behind, as I only had 5 hours total on position. Supplemental information from acn 374793: this incident occurred because the military's king air mode C did not update properly and the OJT instructor's lack of experience conducting training.

Original NASA ASRS Text

Title: OPERROR LTSS BTWN MIL C12 CLBING TO FL220 AND ACR B757 CLBING TO FL210. RPTR IN TRAINING AND THE OJT INSTRUCTOR THOUGHT THE C12 WAS AT FL220 WHEN THE B757 WAS CLRED TO FL210. RPTR SAID THE MIL C12 MODE C ALT READOUT WAS XXX FOR ABOUT A MIN AND A HALF. NO APPARENT ALT VERIFICATION WITH THE C12 BEFORE CLBING THE B757.

Narrative: I WAS RADAR TRAINING ON DEP SECTOR, WITH 5 HRS ON POS AND TRAINER DIDN'T HAVE MUCH EXPERIENCE AS TRAINER. IT WAS A BUSY DEP PUSH. A MIL C12 CLBING TO FL220 AND BEHIND SAME DIRECTION A B757 CLBING TO FL210. THE C12 MODE C HAD BEEN XXX FOR AT LEAST A MIN AND A HALF. I THOUGHT THE C12 WAS LEVEL AT FL220 AND CLBED THE B757 TO FL210. WHEN THE C12 MODE C CAME BACK ON IT SHOWED FL210 CLBING TO FL220. THE B757 WAS ALREADY SHOWING FL200 CLBING TO FL210, WITHIN 5 MI OF THE C12. AT THAT TIME THE C12 WAS TOLD TO EXPEDITE TO FL220 AND THE B757 TO MAINTAIN FL200, BUT SEPARATION WAS ALREADY LOST. I THINK THE C12'S XPONDER WAS NOT WORKING PROPERLY. IT HAD NOT SHOWN AN ALT FOR A WHILE, AND I THINK IF IT WAS WORKING THE B757'S TCASII WOULD HAVE GIVEN A TA OR RA SO AS TO NOT CLB INTO THE C12. I HAD NOT LOST THE PICTURE COMPLETELY, BUT I WAS GETTING BEHIND, AS I ONLY HAD 5 HRS TOTAL ON POS. SUPPLEMENTAL INFO FROM ACN 374793: THIS INCIDENT OCCURRED BECAUSE THE MIL'S KING AIR MODE C DID NOT UPDATE PROPERLY AND THE OJT INSTRUCTOR'S LACK OF EXPERIENCE CONDUCTING TRAINING.

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.