Narrative:

I was flying in our designated practice area with my student. We were practicing slow flight and stalls in preparation for his private pilot flight test. We were flying northbound doing our maneuvers and we encountered an small transport. He was flying wbound proceeding to nashville metropolitan airport for landing. I saw him on our right side about 1 second before he passed underneath us. It happened very fast. Had he been at our altitude it would have been a collision with no time to react by the time we saw him. He must have seen us or was complying with an ATC clearance to descend, because he was descending as he passed underneath us. 30 mins later we landed and we think his tail number was XXX. This was the only small transport with that color scheme parked on the airport. I am sure glad he saw us and was able to avoid us because we didn't see him in time! The visibility was not really a problem at the time. The nashville ATIS was reporting 6 mi in fog and the clouds were reported scattered at 10000'. We were monitoring nashville departure control on 118.4 although we had cancelled radar service. If he were landing at nashville he should have been in communication with the approach controller on 124.0 because of where he was relative to the airport. Since we were on 118.4 monitoring the departure controller, we could not have heard him coming. Our small aircraft did not have altitude encoding capability. We did not have a transponder on board. Nashville is where we are based and is an arsa. It is common practice at our flight school to depart to the east practice area under radar control and cancel radar service at 10 mi so we can maneuver at our discretion. As far as prevention of these situations, there is not really anything that innovative for a pilot to do. All that can be said is maintain vigilance for other traffic, use proper scanning techniques, fly with mode C installed in your aircraft and stay in radio contact with ATC as much as possible. Although I do make an effort to look for traffic when I fly, my head must have been in the cockpit when this happened. His actions saved the day for us all.

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Original NASA ASRS Text

Title: CLOSE PROX GA-SMA GA-SMT EAST OF BNA.

Narrative: I WAS FLYING IN OUR DESIGNATED PRACTICE AREA WITH MY STUDENT. WE WERE PRACTICING SLOW FLT AND STALLS IN PREPARATION FOR HIS PVT PLT FLT TEST. WE WERE FLYING NBOUND DOING OUR MANEUVERS AND WE ENCOUNTERED AN SMT. HE WAS FLYING WBOUND PROCEEDING TO NASHVILLE METRO ARPT FOR LNDG. I SAW HIM ON OUR RIGHT SIDE ABOUT 1 SEC BEFORE HE PASSED UNDERNEATH US. IT HAPPENED VERY FAST. HAD HE BEEN AT OUR ALT IT WOULD HAVE BEEN A COLLISION WITH NO TIME TO REACT BY THE TIME WE SAW HIM. HE MUST HAVE SEEN US OR WAS COMPLYING WITH AN ATC CLRNC TO DSND, BECAUSE HE WAS DSNDING AS HE PASSED UNDERNEATH US. 30 MINS LATER WE LANDED AND WE THINK HIS TAIL NUMBER WAS XXX. THIS WAS THE ONLY SMT WITH THAT COLOR SCHEME PARKED ON THE ARPT. I AM SURE GLAD HE SAW US AND WAS ABLE TO AVOID US BECAUSE WE DIDN'T SEE HIM IN TIME! THE VIS WAS NOT REALLY A PROB AT THE TIME. THE NASHVILLE ATIS WAS RPTING 6 MI IN FOG AND THE CLOUDS WERE RPTED SCATTERED AT 10000'. WE WERE MONITORING NASHVILLE DEP CTL ON 118.4 ALTHOUGH WE HAD CANCELLED RADAR SVC. IF HE WERE LNDG AT NASHVILLE HE SHOULD HAVE BEEN IN COM WITH THE APCH CTLR ON 124.0 BECAUSE OF WHERE HE WAS RELATIVE TO THE ARPT. SINCE WE WERE ON 118.4 MONITORING THE DEP CTLR, WE COULD NOT HAVE HEARD HIM COMING. OUR SMA DID NOT HAVE ALT ENCODING CAPABILITY. WE DID NOT HAVE A TRANSPONDER ON BOARD. NASHVILLE IS WHERE WE ARE BASED AND IS AN ARSA. IT IS COMMON PRACTICE AT OUR FLT SCHOOL TO DEPART TO THE E PRACTICE AREA UNDER RADAR CTL AND CANCEL RADAR SVC AT 10 MI SO WE CAN MANEUVER AT OUR DISCRETION. AS FAR AS PREVENTION OF THESE SITUATIONS, THERE IS NOT REALLY ANYTHING THAT INNOVATIVE FOR A PLT TO DO. ALL THAT CAN BE SAID IS MAINTAIN VIGILANCE FOR OTHER TFC, USE PROPER SCANNING TECHNIQUES, FLY WITH MODE C INSTALLED IN YOUR ACFT AND STAY IN RADIO CONTACT WITH ATC AS MUCH AS POSSIBLE. ALTHOUGH I DO MAKE AN EFFORT TO LOOK FOR TFC WHEN I FLY, MY HEAD MUST HAVE BEEN IN THE COCKPIT WHEN THIS HAPPENED. HIS ACTIONS SAVED THE DAY FOR US ALL.

Data retrieved from NASA's ASRS site as of August 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.