When you build an airplane for a purpose different than it's original design goal it can be difficult.
(Mark, do you have another relatively cheap DM74 prop?)
The Acroduster 2 seems to have been designed with a IO360 angle valve engine w/CS prop on a 20" mount. At least that's what my factory mount is. So I come along wanting a LSA compliant airplane and find I can manage to do it as a single place with a IO320 with metal FP prop on a 24" mount although I had to add a 13# hunk of steel to the generator pad to be within CG with zero fuel.
When I decided to put Marcia in the front pit my woes started and the CG would go aft of limit with less than 12 gal. of fuel which coupled with wanting to stay below 1320# gross posed a problem. Alas the engine went south and most of you know the rest of the story so the issue went away....
Fast forward a couple years and I find myself building another engine. I decided to solve the CG issue for ever by building a longer mount. Meanwhile I sold my old new prop but I have a wood prop which I figured would not only give me extra useful load but be easier on my thin "G" crank flange.
So I start running the numbers to see how long to make my new mount. Bottom line I simply can't do it without making the airplane look stupid not to mention the strength of the mount as you make it longer. It would just barely work 2-place with a 28" mount & metal prop. But with my wood prop it's marginal single place.
If I had a standard solid flange I'd consider a hunk of steel bolted in front of prop to approximate the weight of a CS but probably not with the G flange.
OH WELL
Jack
(Mark, do you have another relatively cheap DM74 prop?)
The Acroduster 2 seems to have been designed with a IO360 angle valve engine w/CS prop on a 20" mount. At least that's what my factory mount is. So I come along wanting a LSA compliant airplane and find I can manage to do it as a single place with a IO320 with metal FP prop on a 24" mount although I had to add a 13# hunk of steel to the generator pad to be within CG with zero fuel.
When I decided to put Marcia in the front pit my woes started and the CG would go aft of limit with less than 12 gal. of fuel which coupled with wanting to stay below 1320# gross posed a problem. Alas the engine went south and most of you know the rest of the story so the issue went away....
Fast forward a couple years and I find myself building another engine. I decided to solve the CG issue for ever by building a longer mount. Meanwhile I sold my old new prop but I have a wood prop which I figured would not only give me extra useful load but be easier on my thin "G" crank flange.
So I start running the numbers to see how long to make my new mount. Bottom line I simply can't do it without making the airplane look stupid not to mention the strength of the mount as you make it longer. It would just barely work 2-place with a 28" mount & metal prop. But with my wood prop it's marginal single place.
If I had a standard solid flange I'd consider a hunk of steel bolted in front of prop to approximate the weight of a CS but probably not with the G flange.
OH WELL
Jack
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