Narrative:

We were approaching on J41 from pie to tlh. WX at tlh was VFR with a ceiling at 2500-3000 ft. The controller cleared us to descend to 2000 ft MSL. Shortly thereafter we noticed an air carrier medium large transport Y depart on runway 9 and check in with the controller. Neither of us knew what altitude he was going to but typically departures at tlh are cleared to 10000 ft MSL. We both assumed the medium large transport would keep climbing (the controller told us afterward by telephone that the medium large transport was assigned to 2000 ft). Airspeed: 200 KTS. The controller pointed out the airport, we called it in sight and also said that the medium large transport was in sight. The controller cleared us for a visual approach to runway 18 at tlh. We had just reached 2000 ft and were level. We were abeam the departure end of runway 9 about 3-4 mi out. The medium large transport was probably just climbing out of 1000 ft and called us in sight. At some point within the previous few moments the medium large transport was given a left turn to 340 degrees. Keep in mind that we assumed the medium large transport would keep climbing. The effect of the turn was to put him on a collision course with us. He would have passed behind us had he held runway heading. We had stopped our descent at 2000 ft and would have descended further for a pattern altitude but we had only just been cleared for the visual approach. At this point we saw the medium large transport start the turn and we became aware of the collision potential. The captain was flying and initiated a right turn away from the other aircraft. Then the medium large transport stopped its climb at our altitude. We (the captain) then banked approximately 60 degrees and dove away. After we received a GPWS warning for terrain closure rate we rolled out of the bank and leveled off at 1500 ft. The medium large transport then pulled up.

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Original NASA ASRS Text

Title: AN ARRIVING AND A DEP ACR COME IN CLOSE PROX NEAR THE ARPT RESULTING IN AN NMAC.

Narrative: WE WERE APCHING ON J41 FROM PIE TO TLH. WX AT TLH WAS VFR WITH A CEILING AT 2500-3000 FT. THE CTLR CLRED US TO DSND TO 2000 FT MSL. SHORTLY THEREAFTER WE NOTICED AN ACR MLG Y DEPART ON RWY 9 AND CHK IN WITH THE CTLR. NEITHER OF US KNEW WHAT ALT HE WAS GOING TO BUT TYPICALLY DEPS AT TLH ARE CLRED TO 10000 FT MSL. WE BOTH ASSUMED THE MLG WOULD KEEP CLBING (THE CTLR TOLD US AFTERWARD BY TELEPHONE THAT THE MLG WAS ASSIGNED TO 2000 FT). AIRSPD: 200 KTS. THE CTLR POINTED OUT THE ARPT, WE CALLED IT IN SIGHT AND ALSO SAID THAT THE MLG WAS IN SIGHT. THE CTLR CLRED US FOR A VISUAL APCH TO RWY 18 AT TLH. WE HAD JUST REACHED 2000 FT AND WERE LEVEL. WE WERE ABEAM THE DEP END OF RWY 9 ABOUT 3-4 MI OUT. THE MLG WAS PROBABLY JUST CLBING OUT OF 1000 FT AND CALLED US IN SIGHT. AT SOME POINT WITHIN THE PREVIOUS FEW MOMENTS THE MLG WAS GIVEN A L TURN TO 340 DEGS. KEEP IN MIND THAT WE ASSUMED THE MLG WOULD KEEP CLBING. THE EFFECT OF THE TURN WAS TO PUT HIM ON A COLLISION COURSE WITH US. HE WOULD HAVE PASSED BEHIND US HAD HE HELD RWY HDG. WE HAD STOPPED OUR DSCNT AT 2000 FT AND WOULD HAVE DSNDED FURTHER FOR A PATTERN ALT BUT WE HAD ONLY JUST BEEN CLRED FOR THE VISUAL APCH. AT THIS POINT WE SAW THE MLG START THE TURN AND WE BECAME AWARE OF THE COLLISION POTENTIAL. THE CAPT WAS FLYING AND INITIATED A R TURN AWAY FROM THE OTHER ACFT. THEN THE MLG STOPPED ITS CLB AT OUR ALT. WE (THE CAPT) THEN BANKED APPROX 60 DEGS AND DOVE AWAY. AFTER WE RECEIVED A GPWS WARNING FOR TERRAIN CLOSURE RATE WE ROLLED OUT OF THE BANK AND LEVELED OFF AT 1500 FT. THE MLG THEN PULLED UP.

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.