CLOSE PROX GA SMA LOW WING PASSED 50' OVER GA SMA HIGH WING.

Narrative

THIS WAS A ROUTINE TRAINING FLT WITH A STUDENT PLT. THE STUDENT WAS PRACTICING FLT AT MINIMUM CTLABLE AIRSPD. THE ACFT WAS IN A LNDG CONFIGN; 30 DEG FLAPS; INDICATING APPROX 50 MPH. WE HAD BEEN FLYING IN THIS CONFIGN FOR SEVERAL MINUTES ON A NE HDG. WHILE IN THE PROCESS OF REESTABLISHING LEVEL CRUISE FLT WE SAW THE LOW WING ACFT PASS ALMOST DIRECTLY OVERHEAD WITH MINIMAL VERTICAL SEP; PROBABLY LESS THAN 50'; ALTHOUGH THE SUDDENNESS OF THE OCCURRENCE MADE THE DISTANCE DIFFICULT TO JUDGE. WE REMAINED LEVEL AT 2700' MSL AND OBSERVED THE OTHER ACFT DIVERGING FROM US ON AN ANGLE TO THE L. I ESTIMATE THAT THERE WAS ABOUT A 30 DEG DIFFERENCE BTWN OUR HDGS. WE HAD HAD NO VIS CONTACT WITH THE OTHER ACFT PRIOR TO SEEING IT APPEAR FROM THE AREA BLOCKED BY OUR R WING AND PASS TO THE L. THERE WAS NO OPPORTUNITY FOR US TO TAKE ANY EVASIVE ACTION. IT SEEMS UNLIKELY THAT THE OTHER ACFT HAD US IN SIGHT SINCE IT DID NOT APPEAR THAT HE HAD BEEN TAKING EVASIVE ACTION. I DO NOT BELIEVE THAT OUR FLT ATTITUDE CONTRIBUTED TO THIS INCIDENT. WE HAD BEEN MAINTAINING AN ALT OF 2700' MSL IMMEDIATELY PRIOR TO; DURING AND AFTER IT OCCURRED. IT IS POSSIBLE THAT; IF THE OTHER PLANE DID HAVE US IN SIGHT; OUR ACCELERATION COULD HAVE CAUSED HIM TO MISJUDGE OUR CLOSURE RATE. I BELIEVE THE LOW WING'S FLT PATH WAS FROM BEHIND AND TO THE R; SO THAT EVEN HAD MY ATTN NOT BEEN DIVIDED BTWN GUIDING THE STUDENT AND SCANNING FOR TFC I STILL WOULD NOT HAVE SEEN IT. I BELIEVE THE MAJOR CONTRIBUTING FACTOR WAS THAT EACH ACFT'S WINGS OBSCURED THE VIEW OF THE OTHER. ONLY IF ONE OR BOTH OF US SAW THE OTHER AT A GREATER DISTANCE COULD THIS HAVE BEEN AVOIDED.