fprintf
Sep 27, 2004, 10:25 AM
I repieced together my Marauder that I had blown up on the winch earlier this year. I fear, however, that I have not repaired it correctly because it doesn't fly as I remember it -- it does not take kindly to gusts of wind nor medium sized control inputs. However at the end of the day when there was no wind I was able to tame the plane and finally able to get it to fly very slow, open thermal circles. Otherwise I was wobbly and all over the place - stalling quite a bit.
Here are the symptoms:
When trimmed for a non-porpoising glide it flies somewhat slowly. If I add up trim the plane slows down and then starts to stall. If a gust comes along in either configuration the plane will balloon and then stall. I need to be vigilant on the elevator at all times. If I add downtrim to the plane it starts to dive.
In turns the plane needs quite a bit of up elevator. However the plane will very easily run out of airspeed and stall. Flying the plane faster with less up elevator usually means it will balloon as it comes into the wind *or* will dive on the downwind side of the turn.
I know the CG is pretty far back, as best I can tell using the fingertip method. I had to add quite a bit of glue and fiberglass to the tail to get the plane back together and only added a small amount of noseweight to compensate. There is a small amount of visible elevator uptrim in relation to the fixed stab. Adding more noseweight does not improve the described symptoms.
So what should I look for? I am thinking I need to make sure there are no twists along the wing. What is frustrating about my experimentation yesterday is that adding noseweight only seemed to add to the amount of uptrim I needed, but did not seem to otherwise change the symptoms. Reading my description about makes it seem like my CG needs to go further forward. Thoughts on some experiments I can run to further diagnose the situation?
Here are the symptoms:
When trimmed for a non-porpoising glide it flies somewhat slowly. If I add up trim the plane slows down and then starts to stall. If a gust comes along in either configuration the plane will balloon and then stall. I need to be vigilant on the elevator at all times. If I add downtrim to the plane it starts to dive.
In turns the plane needs quite a bit of up elevator. However the plane will very easily run out of airspeed and stall. Flying the plane faster with less up elevator usually means it will balloon as it comes into the wind *or* will dive on the downwind side of the turn.
I know the CG is pretty far back, as best I can tell using the fingertip method. I had to add quite a bit of glue and fiberglass to the tail to get the plane back together and only added a small amount of noseweight to compensate. There is a small amount of visible elevator uptrim in relation to the fixed stab. Adding more noseweight does not improve the described symptoms.
So what should I look for? I am thinking I need to make sure there are no twists along the wing. What is frustrating about my experimentation yesterday is that adding noseweight only seemed to add to the amount of uptrim I needed, but did not seem to otherwise change the symptoms. Reading my description about makes it seem like my CG needs to go further forward. Thoughts on some experiments I can run to further diagnose the situation?