Narrative:

We had just passed the eastern edge of the delta airport heading 210 degrees at 10500 ft. After we had station passage on the delta VOR, it was only moments till I saw a twin engine about the size of a piper navajo, though I'm guessing it was a cessna (can't think of a model name) -- it didn't have winglets or tip tanks -- however, it did have squarish windows. When I first saw the plane, it was at about a 30 degree left bank and about 150 ft off my port (left) wing. We were showing about 128 KTS, and I would guess he was doing about 160-180 KTS. We continued on our course of 210 degrees while he appeared to be heading about 180-190 degrees. Note: victor 21-235 is 187 degrees off the delta VOR. When I initially saw him I thought to myself, 'man he's close but we're not converging' or at least we weren't when I saw him, so I saw no need for any corrective or evasive maneuver -- he was already turning away from us. My burning question is, did he see us or did his autoplt just happen to be turning him on course for victor 21- 235. He never changed altitude, just a bank -- and he appeared to roll out on course. When we started our descent, I could still see him on the horizon. What did we learn? Had we been on flight following with ARTCC, we would likely have gotten a radar traffic alert. At the altitude we were cruising, we probably would have been visible on radar, as the MEA for the airway is 10300 ft north of the VOR and 9600 ft south of it. On many missions, we are at cruise for such a short time, it hardly seems worth it to ask for flight following. And many times we are so low, compared to the mountainous terrain, that we don't show up on radar. However, in the future, I'm going to try to be visible on radar, even if it means climbing and even if it will only be for a few mins.

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Original NASA ASRS Text

Title: A CRUISING C182 ACFT IS ALMOST HIT BY A TWIN CESSNA TYPE DURING AN NMAC OVER DTA, UT. PF WAS IN TRAINING FOR THE CAP MISSION, INSTRUCTOR WAS REVIEWING HIS MISSION PAPERS.

Narrative: WE HAD JUST PASSED THE EASTERN EDGE OF THE DELTA ARPT HDG 210 DEGS AT 10500 FT. AFTER WE HAD STATION PASSAGE ON THE DELTA VOR, IT WAS ONLY MOMENTS TILL I SAW A TWIN ENG ABOUT THE SIZE OF A PIPER NAVAJO, THOUGH I'M GUESSING IT WAS A CESSNA (CAN'T THINK OF A MODEL NAME) -- IT DIDN'T HAVE WINGLETS OR TIP TANKS -- HOWEVER, IT DID HAVE SQUARISH WINDOWS. WHEN I FIRST SAW THE PLANE, IT WAS AT ABOUT A 30 DEG L BANK AND ABOUT 150 FT OFF MY PORT (L) WING. WE WERE SHOWING ABOUT 128 KTS, AND I WOULD GUESS HE WAS DOING ABOUT 160-180 KTS. WE CONTINUED ON OUR COURSE OF 210 DEGS WHILE HE APPEARED TO BE HDG ABOUT 180-190 DEGS. NOTE: VICTOR 21-235 IS 187 DEGS OFF THE DELTA VOR. WHEN I INITIALLY SAW HIM I THOUGHT TO MYSELF, 'MAN HE'S CLOSE BUT WE'RE NOT CONVERGING' OR AT LEAST WE WEREN'T WHEN I SAW HIM, SO I SAW NO NEED FOR ANY CORRECTIVE OR EVASIVE MANEUVER -- HE WAS ALREADY TURNING AWAY FROM US. MY BURNING QUESTION IS, DID HE SEE US OR DID HIS AUTOPLT JUST HAPPEN TO BE TURNING HIM ON COURSE FOR VICTOR 21- 235. HE NEVER CHANGED ALT, JUST A BANK -- AND HE APPEARED TO ROLL OUT ON COURSE. WHEN WE STARTED OUR DSCNT, I COULD STILL SEE HIM ON THE HORIZON. WHAT DID WE LEARN? HAD WE BEEN ON FLT FOLLOWING WITH ARTCC, WE WOULD LIKELY HAVE GOTTEN A RADAR TFC ALERT. AT THE ALT WE WERE CRUISING, WE PROBABLY WOULD HAVE BEEN VISIBLE ON RADAR, AS THE MEA FOR THE AIRWAY IS 10300 FT N OF THE VOR AND 9600 FT S OF IT. ON MANY MISSIONS, WE ARE AT CRUISE FOR SUCH A SHORT TIME, IT HARDLY SEEMS WORTH IT TO ASK FOR FLT FOLLOWING. AND MANY TIMES WE ARE SO LOW, COMPARED TO THE MOUNTAINOUS TERRAIN, THAT WE DON'T SHOW UP ON RADAR. HOWEVER, IN THE FUTURE, I'M GOING TO TRY TO BE VISIBLE ON RADAR, EVEN IF IT MEANS CLBING AND EVEN IF IT WILL ONLY BE FOR A FEW MINS.

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.