Narrative:

An IFR student and I were on an IFR training flight in his G1000 equipped DA40 to mgj. We received the mgj ASOS report about 20 miles south as ovc 2600 calm winds visibility 7 temperature/dew point 14/12 baro 30.20. When we were switched to ny control we informed them we had current weather and requested vectors for the ILS 3. We were vectored to the ILS and joined the localizer about 6 miles from FAF of diyad at 3;000 ft in IMC. We were then cleared for the approach; and advised to contact advisory and cancel on the ground when able. We changed to mgj unicom frequency; turned on the lights and announced our approach at 5; 3; and 2 mile final. We continued to descend to FAF at diyad and intersected the glideslope and proceeded down the approach breaking out at 800 ft; visibility estimated about 4 SM. At about 600 ft over the runway approach lights I (the instructor) looked to our left and saw a small tail dragger which looked like an aeronca with white and red markings abeam our left wing at about 200 ft distance horizontally at the same altitude as the DA40. I altered the student/owner; who was the pilot flying the DA40. He immediately reacted by adding power and banking to the right away from the other aircraft. The aeronca banked left away from us. I called the aircraft on common traffic frequency several times. No response. The diamond DA40 is equipped with TCAS traffic avoidance system. It did not register the aeronca. We have to assume the aircraft had no radio (or at least did not have it on the unicom frequency) and no transponder (or did not have it on). It had [hard to see] north numbers; so it might be an older aircraft without an electrical system. These are just conjectures on our part. We do know the aircraft did not respond to us or register on our traffic system. At this point the owner/student had maneuvered the DA40 parallel right of runway 03. The aeronca then maneuvered back right toward the runway 03 and under the DA40 and landed runway 03. After our initial confusion; student/owner advanced the throttle and re-entered IMC at approximately 800 ft MSL and initiated the published missed approach to huo. Fortunately; we had not cancelled our IFR. We called ATC; informed them we had gone missed (but not the reason) and asked to pick up our filed IFR clearance. We were given the IFR clearance after a short delay. In retrospect; though the ASOS reported marginal VFR at mgj; the conditions for our entire route of flight were worse than forecasted or reported. Further; we suspect that a pilot could believe based on the ASOS at mgj; that the weather was better than it actually was and one might be able to perform pattern work. It was not. Bad weather; no radio and no transponder combined to make a near collision with a well equipped IFR aircraft following a filed flight plan with ATC guidance.

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Original NASA ASRS Text

Title: DA40 instructor with student on an IFR flight plan report an NMAC with an Aeronca just after breaking out at 800 FT AGL on the ILS 3 to MGJ. A missed approach is executed by the DA40. The Aeronca had no radio and no transponder.

Narrative: An IFR student and I were on an IFR training flight in his G1000 equipped DA40 to MGJ. We received the MGJ ASOS report about 20 miles south as OVC 2600 calm winds visibility 7 temperature/dew point 14/12 Baro 30.20. When we were switched to NY Control we informed them we had current weather and requested vectors for the ILS 3. We were vectored to the ILS and joined the localizer about 6 miles from FAF of DIYAD at 3;000 FT in IMC. We were then cleared for the approach; and advised to contact advisory and cancel on the ground when able. We changed to MGJ UNICOM frequency; turned on the lights and announced our approach at 5; 3; and 2 mile final. We continued to descend to FAF at DIYAD and intersected the glideslope and proceeded down the approach breaking out at 800 FT; visibility estimated about 4 SM. At about 600 FT over the runway approach lights I (the instructor) looked to our left and saw a small tail dragger which looked like an Aeronca with white and red markings abeam our left wing at about 200 FT distance horizontally at the same altitude as the DA40. I altered the student/owner; who was the pilot flying the DA40. He immediately reacted by adding power and banking to the right away from the other aircraft. The Aeronca banked left away from us. I called the aircraft on common traffic frequency several times. No response. The Diamond DA40 is equipped with TCAS traffic avoidance system. It did not register the Aeronca. We have to assume the aircraft had no radio (or at least did not have it on the Unicom frequency) and no transponder (or did not have it on). It had [hard to see] N numbers; so it might be an older aircraft without an electrical system. These are just conjectures on our part. We do know the aircraft did not respond to us or register on our traffic system. At this point the owner/student had maneuvered the DA40 parallel right of Runway 03. The Aeronca then maneuvered back right toward the Runway 03 and under the DA40 and landed Runway 03. After our initial confusion; student/owner advanced the throttle and re-entered IMC at approximately 800 FT MSL and initiated the published missed approach to HUO. Fortunately; we had not cancelled our IFR. We called ATC; informed them we had gone missed (but not the reason) and asked to pick up our filed IFR clearance. We were given the IFR clearance after a short delay. In retrospect; though the ASOS reported marginal VFR at MGJ; the conditions for our entire route of flight were worse than forecasted or reported. Further; we suspect that a pilot could believe based on the ASOS at MGJ; that the weather was better than it actually was and one might be able to perform pattern work. It was not. Bad weather; no radio and no transponder combined to make a near collision with a well equipped IFR aircraft following a filed flight plan with ATC guidance.

Data retrieved from NASA's ASRS site as of July 2013 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.