Just gathering some info on in-flight adjustable tailplanes - I did the usual google searches etc, but there is always more stuff hidden somewhere.
I refer to tailplanes such as on Cub , hinged at one spar and adjustable, usually via a jack screw mechanism at the other. Instead of re-inventing the wheel, I am gathering data on what has been used in the past.
My current idea applies to a cantilever, sheet metal tail. With a new design, no matter ho many sums you do and conservative assumptions you make, getting the tailplane incidence right is educated guesswork and some means of adjusting it is essential during testing. If it needs to be adjustable, why not make adjustable in flight? A trim system is needed anyway, or at least desirable, and it can mechanically just as complex.
I thought about the usual jack screw arrangement, but without the usual pulley/chain/sprocket system, but using a linear actuator. These are relatively cheap (around $100), come with built in limit switches and are capable of considerable force and holding power, certainly adequate for what I need, Since my airplane is looking to be a tad nose-heavy, the extra pound or two near the tail is actually useful to me. The one in the picture has a 2" stroke, 150lbs force, and has a rated holding power of over 500 lbs. All way more than I require.
Anybody done something similar?
I refer to tailplanes such as on Cub , hinged at one spar and adjustable, usually via a jack screw mechanism at the other. Instead of re-inventing the wheel, I am gathering data on what has been used in the past.
My current idea applies to a cantilever, sheet metal tail. With a new design, no matter ho many sums you do and conservative assumptions you make, getting the tailplane incidence right is educated guesswork and some means of adjusting it is essential during testing. If it needs to be adjustable, why not make adjustable in flight? A trim system is needed anyway, or at least desirable, and it can mechanically just as complex.
I thought about the usual jack screw arrangement, but without the usual pulley/chain/sprocket system, but using a linear actuator. These are relatively cheap (around $100), come with built in limit switches and are capable of considerable force and holding power, certainly adequate for what I need, Since my airplane is looking to be a tad nose-heavy, the extra pound or two near the tail is actually useful to me. The one in the picture has a 2" stroke, 150lbs force, and has a rated holding power of over 500 lbs. All way more than I require.
Anybody done something similar?
