Narrative:

Departed iad on the capital 5 departure, hafnr to gve, as filed. Crossed hafnr at approximately FL190, climbing to FL210. As we turned toward gve, we got a TA on traffic at 2 O'clock position and 3 mi also approximately at FL190, climbing. We increased rate of climb to get vertical separation. In so doing, we inadvertently disengaged the altitude capture mode on the autoplt. ZDC then noted the conflict, asked us where we were going, started to give us a vector, but gave the vector to the commuter aircraft instead. In the next few seconds we got visual contact with the traffic. In the confusion of the moment, we overshot our altitude by 800 ft. As we started back to FL210, center cleared us to FL270. Closest point of approach to traffic was approximately 2 mi and approximately co-altitude. ZDC never told us what caused the conflict, but they did ask both us, and the other aircraft, about our route of flight.

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Original NASA ASRS Text

Title: AN LJ60 CAPT ADMITTED OVERSHOOTING HIS ALT WHILE TRYING TO MAINTAIN SEPARATION FROM ANOTHER ACFT IN ZDC'S AIRSPACE.

Narrative: DEPARTED IAD ON THE CAPITAL 5 DEP, HAFNR TO GVE, AS FILED. CROSSED HAFNR AT APPROX FL190, CLBING TO FL210. AS WE TURNED TOWARD GVE, WE GOT A TA ON TFC AT 2 O'CLOCK POS AND 3 MI ALSO APPROX AT FL190, CLBING. WE INCREASED RATE OF CLB TO GET VERT SEPARATION. IN SO DOING, WE INADVERTENTLY DISENGAGED THE ALT CAPTURE MODE ON THE AUTOPLT. ZDC THEN NOTED THE CONFLICT, ASKED US WHERE WE WERE GOING, STARTED TO GIVE US A VECTOR, BUT GAVE THE VECTOR TO THE COMMUTER ACFT INSTEAD. IN THE NEXT FEW SECONDS WE GOT VISUAL CONTACT WITH THE TFC. IN THE CONFUSION OF THE MOMENT, WE OVERSHOT OUR ALT BY 800 FT. AS WE STARTED BACK TO FL210, CTR CLRED US TO FL270. CLOSEST POINT OF APCH TO TFC WAS APPROX 2 MI AND APPROX CO-ALT. ZDC NEVER TOLD US WHAT CAUSED THE CONFLICT, BUT THEY DID ASK BOTH US, AND THE OTHER ACFT, ABOUT OUR RTE OF FLT.

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.