Less than standard separation between air carrier medium large transport and GA small transport.

Attributes
ACN	85543
Time
Date	198804
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : sax
State Reference	NJ
Altitude	msl bound lower : 16400 msl bound upper : 17000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zny
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : direct
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Transport, Low Wing, 2 Turbojet Eng
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 150 flight time total : 7000 flight time type : 700
ASRS Report	85543
Person 2
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Miss Distance	horizontal : 18000 vertical : 600
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

We had departed lga en route to cle. We were level at 15000' and had been cleared direct to the eliot intersection. The departure controller then issued a climb clearance to 17000'. With the autoplt engaged, we started our climb to 17000 at about 2500 FPM. Passing 15700' the controller told us to level off at 16000', there was small transport traffic at 2 O'clock and 3NM, at 17000'. I disengaged the autoplt and autothrottles and pushed the nose down. Our altitude reached 16400 before I was able to stop the climb. We descended back to 16000'. Neither one of us saw the other aircraft. Several minutes later the controller cleared us to FL230. He never said anything about his amended altitude clearance, our altitude overshoot, or a traffic conflict.

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN ACR MLG AND GA SMT.

Narrative: WE HAD DEPARTED LGA ENRTE TO CLE. WE WERE LEVEL AT 15000' AND HAD BEEN CLRED DIRECT TO THE ELIOT INTXN. THE DEP CTLR THEN ISSUED A CLB CLRNC TO 17000'. WITH THE AUTOPLT ENGAGED, WE STARTED OUR CLB TO 17000 AT ABOUT 2500 FPM. PASSING 15700' THE CTLR TOLD US TO LEVEL OFF AT 16000', THERE WAS SMT TFC AT 2 O'CLOCK AND 3NM, AT 17000'. I DISENGAGED THE AUTOPLT AND AUTOTHROTTLES AND PUSHED THE NOSE DOWN. OUR ALT REACHED 16400 BEFORE I WAS ABLE TO STOP THE CLB. WE DSNDED BACK TO 16000'. NEITHER ONE OF US SAW THE OTHER ACFT. SEVERAL MINUTES LATER THE CTLR CLRED US TO FL230. HE NEVER SAID ANYTHING ABOUT HIS AMENDED ALT CLRNC, OUR ALT OVERSHOOT, OR A TFC CONFLICT.

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.