Pietenpol-List: Landing Gear Toes

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Pietenpol-List: Landing Gear Toes

Post by matronics »

Original Posted By: Brent Reed
> . There is no alignment issue w/ the straight gear> > like you have when you weld up the split gear. It's true from wheel>> > to wheel right away. I hear from those much wiser that a plane> > with wheels pointed in different directions can make it a whole> > different animal. Hopefully others w/ more experience will> > comment. Mike C.> >> >> Taildraggers should be aligned straight or should have a little bit of>> toe out (a couple of degrees). If they are toed in they get really> squirrely.This is correct. The reason is in toed in conditions it is very easyfor the toed in wheel (either if both are toed in) to quickly *very*quickly steer the airplane in to a turn. One may reason well duh,wouldn't a toe out condition cause a turn as well? the answer is YES.The difference is that a toe in turn will tighten because more and moreweight will be place on the toed in wheel until you are tied into aground loop, folding the gear in the process. Toe out will have theopposite effect thus decreasing -to a degree- the tendancy of the tailto swap ends. I know of a Champ that had a real bad habit ofgroundlooping to one side --enough that the pilot-- nor anyone elsewould fly it It was sold in this condition as a lost cause. Beforeflying the new owner blocked, and dropped a plumb bobed the gear andfound that one wheel had toe in of 2-3 degrees on one side and 2-3degrees toe out on the other! In addition the toe out side was a coupleof inches displaced to the rear. After a repair the the plane flew,well, like a CHAMP.No Really!Steve E.________________________________________________________________________________
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Pietenpol-List: Re: Landing Gear Toes

Post by matronics »

Original Posted By: Wkoucky(at)aol.com
> >> > Taildraggers should be aligned straight or should have a little bit of> >> > toe out (a couple of degrees). If they are toed in they get really> > squirrely.> > This is correct. The reason is in toed in conditions it is very easy> for the toed in wheel (either if both are toed in) to quickly *very*> quickly steer the airplane in to a turn. One may reason well duh,> wouldn't a toe out condition cause a turn as well? the answer is YES.> The difference is that a toe in turn will tighten because more and more> weight will be place on the toed in wheel until you are tied into a> ground loop, folding the gear in the process. Toe out will have the> opposite effect thus decreasing -to a degree- the tendancy of the tail> to swap ends. I know of a Champ that had a real bad habit of> groundlooping to one side --enough that the pilot-- nor anyone else> would fly it It was sold in this condition as a lost cause. Before> flying the new owner blocked, and dropped a plumb bobed the gear and> found that one wheel had toe in of 2-3 degrees on one side and 2-3> degrees toe out on the other! In addition the toe out side was a couple> of inches displaced to the rear. After a repair the the plane flew,> well, like a CHAMP.> > No Really!> > Steve E.> > Exactly how I would have explained it mon ami. I know of a similarcase involving a Smith Miniplane who's owners all thought it's evil handlingwas mysteriously cursed by an evil runway handling spirit. When I mentionedthe probablility of toe in being the cause of the problems they had already sold it...D'oh!John________________________________________________________________________________
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Pietenpol-List: Re: Landing Gear Toes

Post by matronics »

Original Posted By: Steve Eldredge
How does one go about measuring toe in or toe out?William________________________________________________________________________________
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Pietenpol-List: Re: Landing Gear Toes

Post by matronics »

Original Posted By: Gary Gower
Wkoucky(at)aol.com wrote:> How does one go about measuring toe in or toe out?>> WilliamIt really isnt that hard but you need a flat surface.Chalk a line and line up the fuse's longitudinal (sp) axis exactly withthe line. Raise the tail to flying attitude. I used seams in thehanger floor. Use another seam or chalk another line perpendicular tothe first and push the plane up so the gear sits on that line. If onewheel gets there before the other this is your first clue that somethingis amiss. Strap a piece of angle iron, very straight board etc to thewheel hub on each side. The line the boards create represents therolling direction of the gear. This line can be measured with referenceto the longitudinal axis of the fuse to find the angle of toe in or toeout. Fixing a problem needn't be too dificult either. build it on ajig and you will be straight to begin with, but if not I have known anavid builder who just stuck a piece of thick wall tubing into the axleand gently but firmly tweeked the correct amount of adjustment in byhand.Stevee________________________________________________________________________________
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Pietenpol-List: Re: Landing Gear Toes

Post by matronics »

Original Posted By: ADonJr(at)aol.com
>How does one go about measuring toe in or toe out?>>William>One way to do it is:First put the wheels off the ground so you can turn them and draw a line inthe center (sometimes the tire is not mounted centered on the rim), then putthe plane in the floor and move it a little back and forth so they (tires)are in their normal position.messure the distance betwn the lines in the front and in the back from tireto tire. The diference will be the toe-in (or toe-out).SaludosGary Gower________________________________________________________________________________
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Pietenpol-List: Re: Landing Gear Toes

Post by matronics »

Original Posted By: Wkoucky(at)aol.com
There's a good, basic article on wheel alignment in Tony Bingelis' book, TheSportplane Builder. He discusses camber and toe-in/out in a way that usnovices can understand. His alignment technique looks practical. TheSportplane Builder is available from EAA....everyone should have a copy bythe workbench!________________________________________________________________________________
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Pietenpol-List: Re: Landing Gear Toes

Post by matronics »

Original Posted By: rdecosta(at)autoeurope.com (Richard DeCosta)
>I have the book but didn't realize the toe in-out question was in there. Thanks.william________________________________________________________________________________
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