Narrative:

Far 135 IOE line check. Our 402C and the second aircraft a twin otter, converged just east of boulder VOR at 5000 ft and 5500 ft respectively. These altitudes are the final segment altitudes for the 2 separate coded VFR departure procedures we were flying. I was PIC, but was not the PF. The PF was in the left seat, I was in the right. We passed 500 ft beneath the otter as the procedures provided, we were heading 150 degrees, the otter 065 degrees as we crossed. Each aircraft was then to perform a turn around hoover dam in order to display this out the left sides of the 2 aircraft. The final cruise altitude for each aircraft was 7500 ft, and our ground tracks were to converge east of the dam. I asked the PF whether he had the otter in sight as we both turned left around the dam and began our climbs. He said he did, and in fact I could also see the otter from my position in the right seat through the PF's side window, then our windshield. I told the PF to turn right and give the otter more room. He did, and we continued our climbs, more or less on the same, but parallel courses. We leveled off at 6500 ft momentarily and called our position abeam, on the right and about 800 ft lower than the otter. The otter crew acknowledged us 'in sight.' we resumed our climb, however I could no longer see the otter due to my position on the right side of the aircraft. I imagined that the otter would fall behind, as we were faster, and assumed the PF still had the other aircraft in sight. Climbing through 7200 ft or 7300 ft, I asked the PF if he still had the otter in sight on his side. As I did so, I leaned over to the left and looked up and out of the PF's side, then looked straight-up through our windshield. The otter was directly above us, 200-300 ft. I took the controls, and without any abrupt maneuvering, arrested our climb and began a smooth descent and turned right 30 degrees to separate ourselves horizontally as well. Soon the otter became visible behind and slightly above us at about 1/2 mi. We continued the flight to our destination without further incident.

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Original NASA ASRS Text

Title: NMAC DURING A SCENIC TOUR AND CLB OUT.

Narrative: FAR 135 IOE LINE CHK. OUR 402C AND THE SECOND ACFT A TWIN OTTER, CONVERGED JUST E OF BOULDER VOR AT 5000 FT AND 5500 FT RESPECTIVELY. THESE ALTS ARE THE FINAL SEGMENT ALTS FOR THE 2 SEPARATE CODED VFR DEP PROCS WE WERE FLYING. I WAS PIC, BUT WAS NOT THE PF. THE PF WAS IN THE L SEAT, I WAS IN THE R. WE PASSED 500 FT BENEATH THE OTTER AS THE PROCS PROVIDED, WE WERE HDG 150 DEGS, THE OTTER 065 DEGS AS WE CROSSED. EACH ACFT WAS THEN TO PERFORM A TURN AROUND HOOVER DAM IN ORDER TO DISPLAY THIS OUT THE L SIDES OF THE 2 ACFT. THE FINAL CRUISE ALT FOR EACH ACFT WAS 7500 FT, AND OUR GND TRACKS WERE TO CONVERGE E OF THE DAM. I ASKED THE PF WHETHER HE HAD THE OTTER IN SIGHT AS WE BOTH TURNED L AROUND THE DAM AND BEGAN OUR CLBS. HE SAID HE DID, AND IN FACT I COULD ALSO SEE THE OTTER FROM MY POS IN THE R SEAT THROUGH THE PF'S SIDE WINDOW, THEN OUR WINDSHIELD. I TOLD THE PF TO TURN R AND GIVE THE OTTER MORE ROOM. HE DID, AND WE CONTINUED OUR CLBS, MORE OR LESS ON THE SAME, BUT PARALLEL COURSES. WE LEVELED OFF AT 6500 FT MOMENTARILY AND CALLED OUR POS ABEAM, ON THE R AND ABOUT 800 FT LOWER THAN THE OTTER. THE OTTER CREW ACKNOWLEDGED US 'IN SIGHT.' WE RESUMED OUR CLB, HOWEVER I COULD NO LONGER SEE THE OTTER DUE TO MY POS ON THE R SIDE OF THE ACFT. I IMAGINED THAT THE OTTER WOULD FALL BEHIND, AS WE WERE FASTER, AND ASSUMED THE PF STILL HAD THE OTHER ACFT IN SIGHT. CLBING THROUGH 7200 FT OR 7300 FT, I ASKED THE PF IF HE STILL HAD THE OTTER IN SIGHT ON HIS SIDE. AS I DID SO, I LEANED OVER TO THE L AND LOOKED UP AND OUT OF THE PF'S SIDE, THEN LOOKED STRAIGHT-UP THROUGH OUR WINDSHIELD. THE OTTER WAS DIRECTLY ABOVE US, 200-300 FT. I TOOK THE CTLS, AND WITHOUT ANY ABRUPT MANEUVERING, ARRESTED OUR CLB AND BEGAN A SMOOTH DSCNT AND TURNED R 30 DEGS TO SEPARATE OURSELVES HORIZLY AS WELL. SOON THE OTTER BECAME VISIBLE BEHIND AND SLIGHTLY ABOVE US AT ABOUT 1/2 MI. WE CONTINUED THE FLT TO OUR DEST WITHOUT FURTHER INCIDENT.

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.