Aircraft climbed to an altitude occupied by another aircraft.

Attributes
ACN	126207
Time
Date	198910
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mia
State Reference	FL
Altitude	msl bound lower : 5000 msl bound upper : 5800
Environment
Flight Conditions	VMC
Light	Dawn
Aircraft 1
Controlling Facilities	tracon : mia
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : initial climbout : takeoff
Route In Use	departure other
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	climbout : initial
Route In Use	departure other
Flight Plan	IFR
Person 1
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 : 5000
ASRS Report	126207
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation non adherence : published procedure
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Miss Distance	horizontal : 12000 vertical : 800
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

We took off from mia and were cleared runway heading to 5000'. As we were climbing out through 4000' we were given climb clearance to 6000'. The 6000 clearance was then changed to 5000. As we were leveling at 5000, controller asked us to state our altitude, which we did. He informed us at that time that he had issued a clearance for 4000'. I informed him that we had received and acknowledged all xmissions with complete call signs and clearance readback and had not received a 4000' restriction. He challenged our response. Factor: we were outclbing another aircraft which had taken off (on the same runway) less than 1 min before us and the controller was trying to provide separation. As we were leveling off at 5000' the controller informed us that the traffic in question was leaving 5800'.

Original NASA ASRS Text

Title: ACFT CLIMBED TO AN ALT OCCUPIED BY ANOTHER ACFT.

Narrative: WE TOOK OFF FROM MIA AND WERE CLRED RWY HDG TO 5000'. AS WE WERE CLIMBING OUT THROUGH 4000' WE WERE GIVEN CLIMB CLRNC TO 6000'. THE 6000 CLRNC WAS THEN CHANGED TO 5000. AS WE WERE LEVELING AT 5000, CTLR ASKED US TO STATE OUR ALT, WHICH WE DID. HE INFORMED US AT THAT TIME THAT HE HAD ISSUED A CLRNC FOR 4000'. I INFORMED HIM THAT WE HAD RECEIVED AND ACKNOWLEDGED ALL XMISSIONS WITH COMPLETE CALL SIGNS AND CLRNC READBACK AND HAD NOT RECEIVED A 4000' RESTRICTION. HE CHALLENGED OUR RESPONSE. FACTOR: WE WERE OUTCLBING ANOTHER ACFT WHICH HAD TAKEN OFF (ON THE SAME RWY) LESS THAN 1 MIN BEFORE US AND THE CTLR WAS TRYING TO PROVIDE SEPARATION. AS WE WERE LEVELING OFF AT 5000' THE CTLR INFORMED US THAT THE TFC IN QUESTION WAS LEAVING 5800'.

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.