Operational error less than standard separation between climbing L101 and a B737 level at FL310.

Attributes
ACN	378374
Time
Date	199708
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : lin
State Reference	CA
Altitude	msl bound lower : 29400 msl bound upper : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa
Operator	common carrier : air carrier
Make Model Name	L-1011 Tri-Star All Series
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : direct
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 6
ASRS Report	378374
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : required legal separation non adherence : published procedure
Independent Detector	other controllera
Resolutory Action	other
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 1600
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Air carrier #1 checked on frequency and was climbed to FL330 and then was pointed out to another sector for direct mlf. Sector receiving pointout referenced traffic that they had just started to handoff. Air carrier #1 was amended to FL290, but didn't read it back. Traffic was quoted to air carrier #1 at 2-3 O'clock position and 3 mi and told to expect higher in 1 min when clear. Reported traffic in sight. Next radar update showed air carrier #1 at FL292. Air carrier #1 was asked to verify level at FL290, and advised he never received that clearance. Air carrier #1 was told to maintain FL290 and report level. These actions were not enough to maintain separation.

Original NASA ASRS Text

Title: OPERROR LTSS BTWN CLBING L101 AND A B737 LEVEL AT FL310.

Narrative: ACR #1 CHKED ON FREQ AND WAS CLBED TO FL330 AND THEN WAS POINTED OUT TO ANOTHER SECTOR FOR DIRECT MLF. SECTOR RECEIVING POINTOUT REFED TFC THAT THEY HAD JUST STARTED TO HDOF. ACR #1 WAS AMENDED TO FL290, BUT DIDN'T READ IT BACK. TFC WAS QUOTED TO ACR #1 AT 2-3 O'CLOCK POS AND 3 MI AND TOLD TO EXPECT HIGHER IN 1 MIN WHEN CLR. RPTED TFC IN SIGHT. NEXT RADAR UPDATE SHOWED ACR #1 AT FL292. ACR #1 WAS ASKED TO VERIFY LEVEL AT FL290, AND ADVISED HE NEVER RECEIVED THAT CLRNC. ACR #1 WAS TOLD TO MAINTAIN FL290 AND RPT LEVEL. THESE ACTIONS WERE NOT ENOUGH TO MAINTAIN SEPARATION.

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.