Narrative:

While on a routine flight from phl to mht I encountered a 'near hit' with a king air, aircraft Y. Our aircraft (air carrier Z) was on an easterly heading (090 degrees) established on the coyle 274 degree radial tracking to the east. I, the captain, was doing the communications work, while the first officer was flying the aircraft with the autoplt engaged. We were level at 5000 ft MSL. Air carrier Z was given a climb clearance from 5000 ft MSL to 10000 ft MSL. At that time, a display of a 'yellow' warning on our radar TCASII was shown indicating a perpetrator in the area. I questioned the ATC and was issued a TA 'traffic 10 O'clock, 3 mi.' we were also given a right turn to 130 degrees. My mind cannot recall if it was with the initial call or a subsequent issuance in regard to this turn. At any rate, many events were about to take place in the next 7-10 seconds. The first officer was rotating the aircraft nose up and starting a right turn. The TCASII warning had changed from yellow to red. Our altitude was estimated at 5050 ft MSL with TCASII red intruder plus 200 ft. TCASII was advising 'descend' vocally, resolve at 2000 ft red dots on vsi. At that time being unable to locate aircraft visually I moved forward in seat. The intruder had been visually blocked by the left side forward windscreen post. First officer had been responding to all TCASII advisory immediately. The mass, inertia, and velocity of our aircraft were being transferred to a descend mode from ascension mode. I, captain took physical control of aircraft because I had made visual contact with the conflict traffic which emerged from the forward windscreen post. TCASII clearance was at 'zero ft' and a singular 'red' diamond on the radar screen at that point. It was my intention to evade the intruder by correcting behind and below him. No other escape was plausible. I rolled the aircraft to the left and continued nose down effort already established by first officer. I believe we were at the transitional arc in flight at this time. The next moment was most terrifying to me, as I saw the 'king air' belly in the forward window along with hearing the 'doppler effect' created from the 'king air' engines. At that point I felt he would surely hit our right wing which was up for the left descending turn. It is my belief I used 30 degree left bank in the evasive maneuver with 10-15 degrees nose down. At 4900 ft MSL I rolled level. From the time I saw the 'king air' until we had missed it was estimated 3-4 seconds. This event left me not only unnerved but practically speechless. When I was able to speak I asked the controller if he realized we just about hit a king air. We then climbed to 10000 ft MSL and continued our flight to mht. Upon reaching mht I called ATC and talked about the incident. I also notified the chief pilot's office as well as dispatch. Upon returning to phl, ATC tower wished to speak to me and he was apprised of the situation.

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Original NASA ASRS Text

Title: AN ACR CAPT RPTS A NMAC DURING CLB FROM PHL. TCASII ALERTED THE CREW BEFORE ATC ISSUED TFC. ACFT CAME WITHIN 50-100 FT VERTLY AND ZERO HORIZLY.

Narrative: WHILE ON A ROUTINE FLT FROM PHL TO MHT I ENCOUNTERED A 'NEAR HIT' WITH A KING AIR, ACFT Y. OUR ACFT (ACR Z) WAS ON AN EASTERLY HDG (090 DEGS) ESTABLISHED ON THE COYLE 274 DEG RADIAL TRACKING TO THE E. I, THE CAPT, WAS DOING THE COMS WORK, WHILE THE FO WAS FLYING THE ACFT WITH THE AUTOPLT ENGAGED. WE WERE LEVEL AT 5000 FT MSL. ACR Z WAS GIVEN A CLB CLRNC FROM 5000 FT MSL TO 10000 FT MSL. AT THAT TIME, A DISPLAY OF A 'YELLOW' WARNING ON OUR RADAR TCASII WAS SHOWN INDICATING A PERPETRATOR IN THE AREA. I QUESTIONED THE ATC AND WAS ISSUED A TA 'TFC 10 O'CLOCK, 3 MI.' WE WERE ALSO GIVEN A R TURN TO 130 DEGS. MY MIND CANNOT RECALL IF IT WAS WITH THE INITIAL CALL OR A SUBSEQUENT ISSUANCE IN REGARD TO THIS TURN. AT ANY RATE, MANY EVENTS WERE ABOUT TO TAKE PLACE IN THE NEXT 7-10 SECONDS. THE FO WAS ROTATING THE ACFT NOSE UP AND STARTING A R TURN. THE TCASII WARNING HAD CHANGED FROM YELLOW TO RED. OUR ALT WAS ESTIMATED AT 5050 FT MSL WITH TCASII RED INTRUDER PLUS 200 FT. TCASII WAS ADVISING 'DSND' VOCALLY, RESOLVE AT 2000 FT RED DOTS ON VSI. AT THAT TIME BEING UNABLE TO LOCATE ACFT VISUALLY I MOVED FORWARD IN SEAT. THE INTRUDER HAD BEEN VISUALLY BLOCKED BY THE L SIDE FORWARD WINDSCREEN POST. FO HAD BEEN RESPONDING TO ALL TCASII ADVISORY IMMEDIATELY. THE MASS, INERTIA, AND VELOCITY OF OUR ACFT WERE BEING TRANSFERRED TO A DSND MODE FROM ASCENSION MODE. I, CAPT TOOK PHYSICAL CTL OF ACFT BECAUSE I HAD MADE VISUAL CONTACT WITH THE CONFLICT TFC WHICH EMERGED FROM THE FORWARD WINDSCREEN POST. TCASII CLRNC WAS AT 'ZERO FT' AND A SINGULAR 'RED' DIAMOND ON THE RADAR SCREEN AT THAT POINT. IT WAS MY INTENTION TO EVADE THE INTRUDER BY CORRECTING BEHIND AND BELOW HIM. NO OTHER ESCAPE WAS PLAUSIBLE. I ROLLED THE ACFT TO THE L AND CONTINUED NOSE DOWN EFFORT ALREADY ESTABLISHED BY FO. I BELIEVE WE WERE AT THE TRANSITIONAL ARC IN FLT AT THIS TIME. THE NEXT MOMENT WAS MOST TERRIFYING TO ME, AS I SAW THE 'KING AIR' BELLY IN THE FORWARD WINDOW ALONG WITH HEARING THE 'DOPPLER EFFECT' CREATED FROM THE 'KING AIR' ENGS. AT THAT POINT I FELT HE WOULD SURELY HIT OUR R WING WHICH WAS UP FOR THE L DSNDING TURN. IT IS MY BELIEF I USED 30 DEG L BANK IN THE EVASIVE MANEUVER WITH 10-15 DEGS NOSE DOWN. AT 4900 FT MSL I ROLLED LEVEL. FROM THE TIME I SAW THE 'KING AIR' UNTIL WE HAD MISSED IT WAS ESTIMATED 3-4 SECONDS. THIS EVENT LEFT ME NOT ONLY UNNERVED BUT PRACTICALLY SPEECHLESS. WHEN I WAS ABLE TO SPEAK I ASKED THE CTLR IF HE REALIZED WE JUST ABOUT HIT A KING AIR. WE THEN CLBED TO 10000 FT MSL AND CONTINUED OUR FLT TO MHT. UPON REACHING MHT I CALLED ATC AND TALKED ABOUT THE INCIDENT. I ALSO NOTIFIED THE CHIEF PLT'S OFFICE AS WELL AS DISPATCH. UPON RETURNING TO PHL, ATC TWR WISHED TO SPEAK TO ME AND HE WAS APPRISED OF THE SIT.

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.