Narrative:

It was decided that since a club member and his dad were coming home; that I would meet them there and take them back to home field. In making the decision I called him and asked about the load he had. He told me they shared a medium suitcase and a couple of small tote bags. He weighed 215 and his father 190. Is sounded like we would be within limits and so the flights were set. I flew our diamond down to bring them back home. Since I am a fairly high time cfii I offered to have him fly the plane which he gratefully did. I did not see him loading the back seat and getting near home I just felt by the seat of my pants that the plane was very tail heavy. I advised him to keep his speed up higher on the approach as in the back of my mind I wanted to avoid a stall which could result in a flat spin unrecoverable possibly even in a rear cg situation. He was doing great only a few feet off the field and I had my thumbs behind the stick as pilots often try to pull way back on it which had resulted in some minor tail strikes on landing (with no damage except the rubber bumper on it). However he overrode my back stop and pulled back hard on the stick (it is noted that our columbia has to be landed that way as it is very nose heavy; the diamond on the other hand is tail heavy). Since he had speed about 15 knots above stall and no power; the plane porpoised and hit the runway twice (the second being worse than the first) at which time I took over and added full power and performed a go around. I was very rattled and my first attempt at landing also resulted in a bounce so I went around again. I regained my composure and my final landing was fairly smooth and we fueled and put the plane away after inspecting it. It showed no apparent damage to either of us but it was later found that a very small scrape on one end of the prop occurred and the plane was referred to maintenance. After my first go around; I asked [the passenger] to shift some weight to the front. Expecting the suitcase; he instead presented me with a rather heavy box of papers which he had on his lap. After all was said and done we did find that we were within the cg required but near the top and back of the envelope. [The club member] had flown the diamond [in the past] but said he had never flown it that heavy. Again; I was not providing flight instruction that return trip but had flown many times with him and found him to be very careful and competent. In light of this event; it was decided that he and I do a presentation at a club meeting defining the extremely different handling characteristics of the two airplanes in hope that something like this does not happen again.

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Original NASA ASRS Text

Title: DA-40 flight instructor reported another pilot over commanded during the landing flare due to aft CG influence and muscle memory from a different aircraft.

Narrative: It was decided that since a club member and his dad were coming home; that I would meet them there and take them back to home field. In making the decision I called him and asked about the load he had. He told me they shared a medium suitcase and a couple of small tote bags. He weighed 215 and his father 190. Is sounded like we would be within limits and so the flights were set. I flew our Diamond down to bring them back home. Since I am a fairly high time CFII I offered to have him fly the plane which he gratefully did. I did not see him loading the back seat and getting near home I just felt by the seat of my pants that the plane was very tail heavy. I advised him to keep his speed up higher on the approach as in the back of my mind I wanted to avoid a stall which could result in a flat spin unrecoverable possibly even in a rear CG situation. He was doing great only a few feet off the field and I had my thumbs behind the stick as pilots often try to pull way back on it which had resulted in some minor tail strikes on landing (with no damage except the rubber bumper on it). However he overrode my back stop and pulled back hard on the stick (It is noted that our Columbia has to be landed that way as it is very nose heavy; the Diamond on the other hand is tail heavy). Since he had speed about 15 knots above stall and no power; the plane porpoised and hit the runway twice (the second being worse than the first) at which time I took over and added full power and performed a go around. I was very rattled and my first attempt at landing also resulted in a bounce so I went around again. I regained my composure and my final landing was fairly smooth and we fueled and put the plane away after inspecting it. It showed no apparent damage to either of us but it was later found that a very small scrape on one end of the prop occurred and the plane was referred to maintenance. After my first go around; I asked [the passenger] to shift some weight to the front. Expecting the suitcase; he instead presented me with a rather heavy box of papers which he had on his lap. After all was said and done we did find that we were within the CG required but near the top and back of the envelope. [The club member] had flown the Diamond [in the past] but said he had never flown it that heavy. Again; I was not providing flight instruction that return trip but had flown many times with him and found him to be very careful and competent. In light of this event; it was decided that he and I do a presentation at a club meeting defining the extremely different handling characteristics of the two airplanes in hope that something like this does not happen again.

Data retrieved from NASA's ASRS site 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.