Air carrier X TCASII RA had less than standard separation from air carrier Y. System error.

Attributes
ACN	312846
Time
Date	199508
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : msp
State Reference	MN
Altitude	msl bound lower : 5000 msl bound upper : 5000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : msp
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude cruise other
Route In Use	departure other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude cruise other
Route In Use	departure other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 240 flight time total : 12000 flight time type : 1440
ASRS Report	312846
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 10000 flight time type : 800
ASRS Report	312845
Events
Anomaly	conflict : nmac non adherence : published procedure non adherence : required legal separation
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	faa : investigated
Miss Distance	horizontal : 0 vertical : 300
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

ATC assigned 2 aircraft same altitude and direction of flight. Air carrier Y had just taken ahead of air carrier X and had been given the same clearance we were. Y was a twin propeller with at least a 70-80 KT disparity. Supplemental information from acn 312845: on departure out of msp at 5000 ft MSL, 040 degree heading we had a TCASII RA to climb, which we did to about 6700 ft. The intruder aircraft was air carrier Y that took off on runway 11L just ahead of us. I asked departure control if they had aircraft on radar, said 'yes. I'm sorry.'

Original NASA ASRS Text

Title: ACR X TCASII RA HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: ATC ASSIGNED 2 ACFT SAME ALT AND DIRECTION OF FLT. ACR Y HAD JUST TAKEN AHEAD OF ACR X AND HAD BEEN GIVEN THE SAME CLRNC WE WERE. Y WAS A TWIN PROP WITH AT LEAST A 70-80 KT DISPARITY. SUPPLEMENTAL INFO FROM ACN 312845: ON DEP OUT OF MSP AT 5000 FT MSL, 040 DEG HDG WE HAD A TCASII RA TO CLB, WHICH WE DID TO ABOUT 6700 FT. THE INTRUDER ACFT WAS ACR Y THAT TOOK OFF ON RWY 11L JUST AHEAD OF US. I ASKED DEP CTL IF THEY HAD ACFT ON RADAR, SAID 'YES. I'M SORRY.'

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.