Air carrier came in close proximity to another aircraft while in descent.

Attributes
ACN	140246
Time
Date	199003
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : mkc
State Reference	MO
Altitude	msl bound lower : 28400 msl bound upper : 29000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zkc
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent other
Flight Plan	IFR
Aircraft 2
Operator	general aviation : corporate
Make Model Name	Light Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : flight engineer pilot : commercial pilot : cfi
Experience	flight time last 90 days : 200 flight time total : 5000 flight time type : 100
ASRS Report	140246
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 190 flight time total : 12000 flight time type : 250
ASRS Report	140242
Events
Anomaly	conflict : airborne less severe non adherence : clearance non adherence : required legal separation
Independent Detector	atc equipment other atc equipment : unspecified other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Miss Distance	horizontal : 3000 vertical : 1000
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

En route to mci eastbound at FL370 we received a clearance to descend to FL240. The captain asked if he wanted us to start down now. Center replied it could be pilot's discretion after FL290. A descent was started and upon reaching an altitude of 28400', center called and said to maintain FL290. An immediate climb was started back to FL290. At the same time center called a southbound light transport at FL280 and told him to start an immediate descent. The light transport passed ahead and below us. Center then asked us what altitude we were cleared to and the captain replied, 'pilot's discretion to descend and maintain FL240.' center replied, 'negative, you were only cleared to FL290.'

Original NASA ASRS Text

Title: ACR CAME IN CLOSE PROX TO ANOTHER ACFT WHILE IN DESCENT.

Narrative: ENRTE TO MCI EBND AT FL370 WE RECEIVED A CLRNC TO DSND TO FL240. THE CAPT ASKED IF HE WANTED US TO START DOWN NOW. CENTER REPLIED IT COULD BE PLT'S DISCRETION AFTER FL290. A DSCNT WAS STARTED AND UPON REACHING AN ALT OF 28400', CENTER CALLED AND SAID TO MAINTAIN FL290. AN IMMEDIATE CLB WAS STARTED BACK TO FL290. AT THE SAME TIME CENTER CALLED A SBND LTT AT FL280 AND TOLD HIM TO START AN IMMEDIATE DSCNT. THE LTT PASSED AHEAD AND BELOW US. CENTER THEN ASKED US WHAT ALT WE WERE CLRED TO AND THE CAPT REPLIED, 'PLT'S DISCRETION TO DSND AND MAINTAIN FL240.' CENTER REPLIED, 'NEGATIVE, YOU WERE ONLY CLRED TO FL290.'

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.