Narrative:

We were flying into an air traffic area at mhk. We contacted the tower 15 mi east of the airport and had just cancelled IFR with ZKC. The WX was good VFR. The tower told us to report and enter a 3 mi left base for runway 21 which was the active runway. I acknowledged this and we continued inbound to the airport. The winds were out of the southwest at approximately 10 KTS. We then entered a 3 mi left base with the before landing check complete. All exterior lights were on and working. At this time I reported our position to ATC. The tower cleared us to land on runway 21 and I acknowledged the clearance. The first officer, flying this leg, was established on the centerline of the runway on final approach at approximately 2800' MSL and a 2 mi final. At this moment the first officer and I noticed an aircraft at our 10:30 position that was operation direction closing fast. We both simultaneously pulled up and made quick right bank as the approaching aircraft then flew underneath us. I then took control of the aircraft and landed west/O further occurrence. I am not sure why the other aircraft was on the final approach course opp direction to the active runway, as we had not been advised of any aircraft in this position. I feel our being alert and maintaining a constant scan allowed my first officer and I time to react to the situation. We were following all ATC and far procedures at all times.

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Original NASA ASRS Text

Title: CLOSE PROX COMMUTER-LTT GA-SMA.

Narrative: WE WERE FLYING INTO AN ATA AT MHK. WE CONTACTED THE TWR 15 MI E OF THE ARPT AND HAD JUST CANCELLED IFR WITH ZKC. THE WX WAS GOOD VFR. THE TWR TOLD US TO RPT AND ENTER A 3 MI LEFT BASE FOR RWY 21 WHICH WAS THE ACTIVE RWY. I ACKNOWLEDGED THIS AND WE CONTINUED INBND TO THE ARPT. THE WINDS WERE OUT OF THE SW AT APPROX 10 KTS. WE THEN ENTERED A 3 MI LEFT BASE WITH THE BEFORE LNDG CHK COMPLETE. ALL EXTERIOR LIGHTS WERE ON AND WORKING. AT THIS TIME I RPTED OUR POS TO ATC. THE TWR CLRED US TO LAND ON RWY 21 AND I ACKNOWLEDGED THE CLRNC. THE F/O, FLYING THIS LEG, WAS ESTABLISHED ON THE CENTERLINE OF THE RWY ON FINAL APCH AT APPROX 2800' MSL AND A 2 MI FINAL. AT THIS MOMENT THE F/O AND I NOTICED AN ACFT AT OUR 10:30 POS THAT WAS OP DIRECTION CLOSING FAST. WE BOTH SIMULTANEOUSLY PULLED UP AND MADE QUICK RIGHT BANK AS THE APCHING ACFT THEN FLEW UNDERNEATH US. I THEN TOOK CTL OF THE ACFT AND LANDED W/O FURTHER OCCURRENCE. I AM NOT SURE WHY THE OTHER ACFT WAS ON THE FINAL APCH COURSE OPP DIRECTION TO THE ACTIVE RWY, AS WE HAD NOT BEEN ADVISED OF ANY ACFT IN THIS POS. I FEEL OUR BEING ALERT AND MAINTAINING A CONSTANT SCAN ALLOWED MY F/O AND I TIME TO REACT TO THE SITUATION. WE WERE FOLLOWING ALL ATC AND FAR PROCS AT ALL TIMES.

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.