Hello to you all,
I'm dealing with a configuration issue with my project. I'm a beginner amateur in aircraft design and found that borrowing an airworthy wing design could put away anxiety about designing a whole aircraft (that's quite picky with a whole new wing design). So my interest in the UltraPup wing design is all about. But the UltraPup has a Gottingen 15% thick airfoil with a high Cm (-0.12 about) and because it is short (17.3 ft long) this 3/4 piper cub replica has to be flown solo from the rear seat.
If you inspect the side view of my project, you can see that side by side pilots are seating at the front spar fuselage junction station that is exactly the position of the front seat of the UltraPup design.
I plan to put fuel tanks behind seats in the fuselage, that could lead to a more suitable CG position, but what about with little fuel, same problem.
Is this in your opinion just a trim issue or is it too much forward loaded ? My concern is perhaps a bit overstated, because tail cone will be all aluminium monocoque and be stress overbuilt (I want it as strong as a truss), so heavier than a steel truss.
I put you stick fixed free neutral point calculus, a lead ballast (few pounds) can be also an answer at tail.
I'm dealing with a configuration issue with my project. I'm a beginner amateur in aircraft design and found that borrowing an airworthy wing design could put away anxiety about designing a whole aircraft (that's quite picky with a whole new wing design). So my interest in the UltraPup wing design is all about. But the UltraPup has a Gottingen 15% thick airfoil with a high Cm (-0.12 about) and because it is short (17.3 ft long) this 3/4 piper cub replica has to be flown solo from the rear seat.
If you inspect the side view of my project, you can see that side by side pilots are seating at the front spar fuselage junction station that is exactly the position of the front seat of the UltraPup design.
I plan to put fuel tanks behind seats in the fuselage, that could lead to a more suitable CG position, but what about with little fuel, same problem.
Is this in your opinion just a trim issue or is it too much forward loaded ? My concern is perhaps a bit overstated, because tail cone will be all aluminium monocoque and be stress overbuilt (I want it as strong as a truss), so heavier than a steel truss.
I put you stick fixed free neutral point calculus, a lead ballast (few pounds) can be also an answer at tail.
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